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Depth of water sensing

Depth of water sensing

Depth of water sensing

(OP)
I would like to monitor the water depth in  well.  Maximum depth is 500" and minimum is 0'.

I have been thinking pressure sensor but everything I have found is quite expensive packaged sensors.

Any ideas on other ways to monitor depth or sources of something I can use for a sensor in a 500' well.

RE: Depth of water sensing

Mount a pulley wheel above the well. Wrap a couple of turns of rope around it. Suspend something that floats on one end of the rope and something that sinks on the other such that when one is at the top the other is at the bottom. As the float moves up and down with the water level, count the number of turns of the pulley wheel. With the right choice of pulley diameter you could either count the turns with a mechanical or electrical up/down counter or arrange to turn a pointer by using gears driven by the pulley.

RE: Depth of water sensing

(OP)
Thanks.  An interesting idea but I think there may some implementation issues.  First of all the pipe, power wire, and safety cable are not necessarily tightly clustered or even in the center of the 6" shaft and they may interfere with the "sensing" cable.  I am also not sure how to arrive at a float that would fit and work with the sinker while 500' of rope changes sides of the pully.  I will mull this over.

I really only get one chance if I need to attach anything to the pump end if I am going to try that.  I have to hire big equipment to take the pump in or out.  I have to do this in the next two weeks.

Thanks again for your idea.

RE: Depth of water sensing

How accurate do you have to be?  On my home sump pump, I have 2 wire that sense the water level.  If sensor 1 gets wet, then it turn on the sump.  If sensor 2 gets wet, then it sounds an audible alarm.  Perhaps, if you only need a couple of differnt key water levels, then something like that might work.  The nice thing about that implemenation is that the sensors can get mounted to the side of the well, and should not interfere with the readings.

Just a thought.

RE: Depth of water sensing

(OP)
As I noted I need 0-500'.  I am not turning on a pump, I want to monitor well performance.

RE: Depth of water sensing

I think you missed the whole point!  If you are simply trying to see if the water level has reached certain level (like 100', 250', 375' and 400'), you can simply place water sensors at the different levels.  However, if you need to know the level to 0.000001mm, this solution won't work.  So I must ask the same question again, how accurate to you need to be?

RE: Depth of water sensing

(OP)
Yes, sorry, I did miss the point.

Note to self: don't post while attention is elsewhere.

I would like to see 10'. Less would be nice. I want to log and analyze the draw down rate over an extended period of time to determine probable long term reliability.

The pump will operate at about 2 GPM.  If the recharge rate is less than this I will see a drawdown in the well level.  I want to be able to see how fast the well is emptying. In normal operation the pump will not necessairly run for a long time and if I have a large granularity I will not easily see early trends in supply.

A bit of background.  I am concerned because this will be the only water supply.  The well was difficult.  605' of solid rock produced slightly less liquid than I can with my kidneys and a six pack (well maybe a 12 pack).  Brought a guy 300 miles to apply high pressure water to fracture the rock.  This injects a large amount of water in the process.  Subsequent "proving" of the well did not seem to me to extract the amount of water injected.  I am also concerned about short and long term trends because I have no idea where the water is comming from.  It is unlikley to be an aquifer based on the materials brought up by the drill. I could have a real problem and not find out for a while. I am just trying to placate my paranoia.

RE: Depth of water sensing

Lateral thinking!

It seems to me you have put the cart before the horse!  Use dowsing rods to find out if there is water and what depth it's at.  This presupposes you know how to douse or can track down your local water divining expert.  Don't laugh at the technique it really works, I have used it to locate sewers.

The only measurement techniques that will solve your problem otherwise are ultrasonic sensors and down hole pressure sensors and you are talking about expensive bits of kit for your depth.

Can you drop a smallbore pipe down the hole?  500 ft of even smallbore pipe is going to weigh some, but if you attach a pressure sensor at the top end then via a tapping introduce compressed air until you can detect air bubbling up to the free surface of the well.  Shut off the air supply and the pressure remaining will give you the depth of water. 32 feet for every atmosphere (14psi).  Temperature aand atmospheric pressure variation may give you some problem but to get the accuracy you require it may be good enough. This should continue to work without any further attention

Good Luck!

RE: Depth of water sensing

(OP)
In point of fact, the dowser ($175 US) said at the exact center of where we drilled there would be 20 GPM at 135'.

RE: Depth of water sensing

Or place the pulley/float assembly in a tube and poke lots of hole in to allow water to fill the tube.  Then the previous solution might work....

RE: Depth of water sensing

Assumming that the pump starts at a certain pressure, either or a combination of the following indirect measurements might work. After the motor inrush current and interia of the column are past: 1. measure the current drawn by the motor, 2. measure the flow rate.

Of course there is the problem of calibration.  However, the pump manufacturer may have some data available. Get one point at installation with a float and a lonnng piece of twine. At mimimun you should be able to see long term trends.

RE: Depth of water sensing

To measure the depth you are going to have to put down a small diameter tube the entire depth of the well, right down to the bottom. Maybe a 1/8" diameter brass tube. Before you put it down, you are going to have to seal the top end with a pressure sensor. In the 70s I used the National LX1600 but I don't think this is available any  more. Motorola have the MPX series sensors now.
It is important that the top of the tube be sealed before it goes down the well as the amount of water forced up the tube will increase the air pressure in the tube in proportion to the depth. If the seal is lost, your calibration will be lost.
However, you will have to calibrate the depth sensor empirically but by looking at the spec sheet for whatever sensor you use, and knowing the length of tubing you will be able to calculate from the air pressure, the depth of water. Higher air pressure = higher water level.

RE: Depth of water sensing

Suggestion: if your going to monitor electrical parameters to determine if the well is 'dry' or not, monitor the power to the motor not just the current. The power is much more linear with head pressure vs. current. If the supply voltage remains constant as well as the frequency, then monitoring the power to the pump motor could, theorhetically, tell you the head pressure. There is down hole pressure monitoring equipment. I have installed some on large submersible pumping equipment. They generally failed rather quickly since the signal was piggy backed on the main current carrying conductors feeding the motor. Check out www.centrilift.com
Good luck

RE: Depth of water sensing

Use an open-ended piece of symmetrical TV cable and
measure the reflection time.

<nbucska@pcperipherals.com>

RE: Depth of water sensing



water water everywhere nor any drop to drink,
water water everywhere and all the boards did shrink...

sounds like you've discovered the joys of having your own well...

surprized that hydrofrac was used.


depending on your well size, pick up a cheap video camera and drop it down the hole, it should reach terminal velocity pretty quickly, when you hear the splash you can tell where the water level is +/-.

RE: Depth of water sensing

(OP)
I have had the joy of owning a well several times before.  But never to this level of sheer enjoyment.  One failed well pump yielded my wife (a longer story) so they are not all bad.

I could also compress a Rolls Royce to 6", put an insulating layer around it and stick it down the well.  It would probably reach the water. Using a simple continuity sensor to detect grounding of the RolaR-probe through the well water I could determine depth.

Using an automated 500' derrick to support the RolaR-probe, I could include a feedback loop to raise and lower the RolaR-probe to track levels.

RE: Depth of water sensing

I like the motor monitoring idea, however here is a different, unrealistic idea:

Heat the air above the column of water in the well.  Put a thermistor in the bottom of the well and in the output water at the top of the well.  Calculate the temperature difference and from that determine how long the water was travelling in the pipe exposed to the warmer air.

Steven

RE: Depth of water sensing

(OP)
I have been able to get the current vs pumping lift from the manufacturer.  I do not have it for the full range needed, but a reasonable subset.  Per the manufacturers spec, current is largely independant of applied voltage, so current in a leg (3 phase) is a reasonable measure of lift height.

The next most suitable solution would probably be a tube with a pressure sensor at the top of the well.  The detail on this would require a presure fitting and pressurizing after installation.  With 500 feet of tube it is probably impractical to seal it before installation.  Eventually air would be absorbed by the water in the tube so external pressurization would also be necessary.  Not a problem to implement, but monitoring current is easier.

Thanks for all of your suggestions, both thoughtfull and spurrious.

RE: Depth of water sensing

Glad I could be of help.

RE: Depth of water sensing

i would try dropping a piece of polly pipe down the well leaving both ends open, drop a piece of resistance wire down the center of the polly.
the polly will insulate the resistance wire from anything it might touch on the way down.

Then (presuming that you arent getting distilled water out of your well) the water will conduct sufficiant current to be able to mesure a resistance between it and the top of your wire.

the ammount of resistance will vary depending on the depth, and should be linear for the best part, and comply with:
Depth = (the oms/foot of the combination of resistance wire and water)*(the mesured resistance of the wire)

i can see this as being a cheap reliable and acurate way of mesuring the depth with a minimum of fuss

you could even pump a constant 100mA down the wire and use a comparator op amp set up to have a gain of the desired value (so that the output had say a variation of 1V/foot) and run the output to a digital voltmeter to read off depth directly as (as the voltage would be at a 1:1 ratio to depth in feet)

just a tought to ponder is all

RE: Depth of water sensing

This will work well in theory... But, you will find that the metallic conductor will quickly oxidise due to the current and also due to time and the impurities in the water…

You may recall these experiments from high school chemistry…

RE: Depth of water sensing

You can send a seperate tube down and pump air to it so it bubbles.  This is basically like a low tech pressure relief valve.  Pressure is a function of the depth of water from the bottom of the tube.  Roughly 15 psi for every 32 feet.  So just measure the pressure in the supply line.  Simple and accurate.  Just have to have a pressure source higher that what will be expected and have a small bleed oriface into the sense tube.  

RE: Depth of water sensing

I have to concur with Chuckles157.  I currently am making a level sensor system (with LCD digital output inside my house) to measure level in my 15' well also.  I have found the Motorola Sensors to be very cheap & there is tons of online help with circuitry etc.  Can get it compensated & integrated (amplified signal) as well.

RE: Depth of water sensing

(OP)
I have looked at the Motorola parts.  The catch is a maximum pressure of 150 PSI.  Even at 400 feet the pressure would be 173 PSI (ft/2.31).  My static level is somewhere between 50 and 100 feet down with the pump at 500 feet down.

I will poke around some more.  The sensor says it can do differential so I could potentially 'bias' it with a bit of plumbing and mechanical work.  Then use two to get the range.

If I could get the range I need I think I could put down a plastic pipe.  I would need threaded pipe which is hard to find. I could put the tube down then measure static level and adjust the pressure to match this water depth.  If I could get that much air pressure.

Copper would have a couple of issues; galvanic activity and to get a continuous run you would need to use bendable tubing and if it is not straight it will be hard to put down the hole.  The hole is not real smooth.

I put the pump down the hole yesterday and today I am plumbing and wiring.  I should finish the power supply for the pump (48 VDC) tonight and try for water tomorror.

RE: Depth of water sensing

Take a parallel TV cable -- cut of a long enough piece
and insulate the end with a blob of epoxy, asphalt, etc.

Build an oscillator with it as a tuned circuit and measure
its frequency. Calibrate it.

<nbucska@pcperipherals.com>

RE: Depth of water sensing

(OP)
I thought I would add this to this to my original post since I was not sure where to ask.

Background: The controller for the pump was flakey from the start.  Just replaced by the manufacturer.  It is an entirely new design.  I think the old one was some sort of analog implementation and this one is more digital. Circuit board is maybe 25% the size of the old one. The previous low water sensor was supposed to work with the new controller (current between a probe and the pump body), needless to say it does not.  I am taking the opportunity of dropping a new sensor down the well to put a tube down to implement the previous suggestions about that approach.  I have the following problem:

It has been too long since I had to do arithetic. The gray cells involved appear to have died.

I have 500' of 1/4" OD, 1/8" ID , 0.921 specific gravity, polyethylene tube going down a well. It will be used as a depth sensor by pressurizing with air to indicate water depth (around 200 psi max).  The tubing weighs about 7.4 lb (probably includes the spool).

Roughly how many lbs of force will this exert on the weight pulling it down into the well.  Positive (float) or negative (sink).  I need to determine the proper weight of the device on the end of the tube and it is not handy to just add weight.  Thre are some other issues with that.

RE: Depth of water sensing

I concur with Operahouse.  A bubbler would be the simplest method that you can use.  If you take the time you could make a new face for the pressure guage to read in feet of water.  Or even purchase a guage that is calibrated in feet of water.

The second simplest method would be to use Metratape (sp).  It is kinda like the old twin lead-in wire for TVs.  It works by the water on the outside of the tape squeezing the tape and shorting out the resistance wire on the inside of the tape.  

RE: Depth of water sensing

Me too.

The bubble method is commonly used to data log water level in rivers, reservoirs and sewers. The usual method uses some sort of electrical air pump and a (dry) air pressure transducer. The pump only needs to start and run while making the actual measurement. Pressure can leak away, and water climb back up the pipe between measurements, the only disadvantage might be possible pipe blockage. Keeping it bubbling very slowly will prevent the possibility of blockage at the pipe entry by silt or debris.

By slowly I mean perhaps one very small bubble per minute.

Pressurizing the pipe could also be achieved with a cylinder of bottled gas, a pressure regulator, a needle valve (to set a very small flow), and a solenoid to shut off the flow totally when not being used. A small cylinder might easily last a year or more. That is better than a motor driven pump if the thing has to run from batteries.

These systems can be made very accurate, and they are simple and reliable.  Commercial water level data loggers are available, and I once repaired one, but they are not cheap.

RE: Depth of water sensing

alternety;  

If you have ALL five hundred feet under water and run the bubbler so the line is charged with water you will have:

2.66lbs of buoyancy because of the air
0.63lbs of buoyancy because of submerged polyethylene

For a total buoyancy of 3.29lbs

If you have 300 feet actually underwater then you will have (300/500) * 3.29lbs = 1.97lbs


As for greymatter fading... it was all those 12packs that you tried to match your kidneys with your well flow.. :)

RE: Depth of water sensing

Cripes did I say charged with water? I meant air!

I will stop my 12 pack-kidney output test now...

RE: Depth of water sensing

Archimedes had the right idea.  Try sitting in the bath for a while.

RE: Depth of water sensing

(OP)
Thanks itsmoked, and everyone else taking the time to respond.   When I posted my message I got to thinking about the pressure. While this was going on I looked at shop air compressor specs.  Oops. I won't be able to charge the line with a reasonable compressor.  But a comment from warpspeed about small gas cylinders is a real idea.  I am going to poke around and see if there is a cheap small cylinder that I can get with CO2 or something in it at the required pressure. If I can't I will probably have to scrap the tube idea.

Archimedes is involved in more ways than one.  I believe the pump is one of his designs.

I need to go find my current well benchmark 12 pack and contemplate some more.

RE: Depth of water sensing

hehehe

You are welcome.

You really need to figure out your water column depth.

  Normally I think most wells oscillate seasonally only about 100ft max. that would only be about 40 psi.  You can certainly try a standard air compressor first, even a 12VDC car junky compressor. You will need a regulator because with that absolutely tiny tube ID 500 ft of tubing will have horrendous restriction to flow.  This could cause a really large pressure drop of many PSI which translates to many feet of error.  This is why they are called bubblers because you truely must have only an occasional bubble popping out.  Otherwise that pressure drop will get you.

  I have never ever heard of a bubbler running more than 10 or 20 feet.  They are primarily used in low head situations in sewage or some gooey putrid material where the hassle of plugged pressure sensor orifices makes the hassle of providing air pressure the only route availble.  To solve the flow problem, normally a pipe with a large ID is used so restriction is not an issue. Furthermore changing head pressure is not an issue over some 10 foot delta.

  If it were me I would cut immediately to the chase.  Buy a waterproof S.S. ABSOLUTE 4-20mA 200psi pressure transducer which by itself will sink.  Tie it to some water proof cable and chuck it in the hole. Excite it with 24VDC. Put a resistor in series with it. The 4-20mA current will entirely negate voltage drop concerns of the 1000ft round trip of wire (499 Ohms will give 10Vs at 200psi).  Lower the transducer while watching a cheapo DMM.  As soon as the voltage stops rising on the DMM you have hit the bottom. Anchor the cable and watch your DMM.  It will be giving you the instantaneous depth.  Scale that resistor anywhere you want your computer to read/log and away you go.

   This is what I do when monitoring water hammer in power plant surge towers during load dumps.

RE: Depth of water sensing

(OP)
itsmoked - that is the same chase I initially cut to.  That was until I tried to price those sensors.  Way too pricey was all I could find.

The water column is 470'.  

This level correlates extremely well with where the well casing ends and the well transistions from dirt to solid granite. I suspect that the water may actually be leaking out at this point when it is full.  Maybe not.  Just as an aside, I also have highly reflective/refractive clay with a less than 0.20 micron size and containing Mn and Fe. This could be coming from a leaky interface as well.  I am on the side of a good sized hill with water running down that dirt/rock interface.  It was also hydrofracted and I believe looking at the logs that the last pressure shot broke through to the surface of the rock. If is not a simple well.  Sure not what I thought I was getting myself into when we bought the lot.

I don't think the pressure drop will be an issue.  If I just pressurize the tube and monitor pressure it is essentially a static environment within the tube.  The movement of the well level is, I believe, slow enough that the system could be treated as a static system.  If there is no flow, will there be a pressure drop?  I don't think so.

RE: Depth of water sensing

I'm sorry I'm still not understanding.. Is there 470ft of water standing in the well? If there is why would someone proceed another 400ft down?  I'm not getting it. :(

You must mean the water starts 470ft down and goes down to 500ft?  Tell me this is what's happening.. pleeeease!

RE: Depth of water sensing

(OP)
Right the first time.  470' of standing water in the well.  The well is actually 605' deep.  We kept drilling to find water and finally called it off at 605. The pump is down 500' because it is a low productivity well.  I have a pump that does about 3 - 3.5 GPM and it will empty the well. The pump speed is actually somewhat adjustable and when I find out what the actual recharge rate is I will set the pump so it will not empty the well.  500' worked out as a good comprimise with costs.  Going further would have meant moving from #6 wire to #4 wire.  A non-trivial difference.  We think most of the water is entering at about 400' down from a video examination but are not real sure.  It was examined before hydrofracting but not after.

The depth also gives some extra storage.  If I did the math right it gives me 98 cubic feet and 733 gllons.

RE: Depth of water sensing

Wow... So you have some wild dynamics down that hole.

This is why you need a down hole pressure sensor...

If you have say 470ft of H2o standing above the bottom of your bubbler tube you need 203psi to just barely get a bubble out the bottom.  This would be at the no (air) flow rate.  Now the pump kicks on and starts dropping the well level. It drops 300ft. Now you would only need 74psi to still only barely have air flow. At 203 psi, air would now be flying down that tube. You would then have the pressure drop I mentioned.. Things would not be happy.

What you really need to make this work, is FLOW control of the air. You need a *flow* sensor and an electrically controlled orifice. You then use a computer to control the orifice to maintain next to nil air flow at all water depths.... Is this easier or less expensive than a single pressure transducer??!?!  A transducer that provides your signal already in a form your controller can use?

Keep in mind the bubbler will also have some lag, possibly causing control dificulties.  

Also I gare-un-tee you will have valve and air compressor headaches.

I just cannot see how your tubing, weight, flow meter, analog orifice/valve, flow controller, compressor, electricity(compressor), maintenance (all of the above), can come close to the price of a single pressure tranducer on the end of a couple hundred feet of 2 wires and a resistor..

BTW your idea to control the pump is a great one. I put a three phase pump down my hole then ran it with a VFD from single phase power.  I could run the pump at any speed. I had it ramp up and down.

RE: Depth of water sensing

A cheap pressure transducer such as Digikey 480-1926-ND, 0-30 psig at $30 seems simple enough to me.  5V powered, 0.5-4.5V o/p.  500" = 18 psi

Mount it at the top of a pipe pushed to the bottom of the well, with some air pumped in and measure the pressure of the head of air as this is not a waterproof sensor.

RE: Depth of water sensing

Hi BrianR I think you misread the previous posts.... You are correct about 500inch system unfortunately we are talking about 6,000 inch system. (500ft)

RE: Depth of water sensing

I guess I got confused with the original question which says 500" on line 1 and 500' on line 3.

500' = 217 psi but it's still do-able using eg a 19C500PA2K 0-500 psia sensor costing $73

RE: Depth of water sensing

I have been thinking about how to monitor the very low air flow through the well bubbler, and the obvious way is to fit a small bubble chamber into the above ground airline.

That could easily be built to run at the required 200 psi static pressure, and have a window through which flow could easily be observed.

The bubbles might even be counted or measured automatically with some sort of optical detector.

RE: Depth of water sensing

Howdy Warpspeed.

I'm not sure I follow you...

Do you realize that *normally* you have your pipe going down into your tank.

You screw a TEE onto the top.

You screw a pressure sensor into one leg of the TEE.

You screw a needle valve into the other leg of the TEE.

You put anohter nipple and another TEE after the needle valve.

You screw a pressure gauge into this second TEE.

You screw a regulator into the other side of this TEE.

You hook an air source to the regulator.

Then you set the regulator to just a high enough pressure  to force the tank material out the bottom of the pipe.  

Then you reduce the flow to the lowest possible flow with, the tank to be measured full, using the needle valve.

Now as the tank level drops the flow will go up because less pressure is required but because you are only talking 10 or 20 feet *normally* and you normally used a 3/4" pipe, there still won't be any appreciable flow related pressure drop to screw up the depth reading.

But in alternety's well case with a huge dynamic head and a miniscule pipe that is hundreds of feet long... Pressure Drop City.

But I digress.

You probably know all this Warpspeed but I don't understand your chamber idea.  There would never be bubbles at the well head.  The bubbles would be at the top of the water column a hundred feet down.

Help me out here.

RE: Depth of water sensing

(OP)
One of my posts disappeared.  What I said was that I have not been clear.  I am not going to run bubbles.  I am going to put the tube down the hole, build stuff on top, fill the tube with the little 12 tire pump until it runs out the bottom.  Close off fill valve, remove pump, and just monitor air pressure to see depth of water.

Additional stuff.  I tried looking at the sensor suggested above but the Honywell site is not doing much more than bitching about SQL server when I try.  What I did see from Digikey seems to show no internal electronics (just a raw bridge) and I am not sure how electrical connections are made to the package.

Bubble counting - just drop a video camera down to monitor the bubbles.  Use a PC with sufficient performance to do video analysis of field of view and do OBR (Optical Bubble Recognition). Given the depth of my well the software would have to be configured to ignore scans of Sampan bottoms.

RE: Depth of water sensing

itsmoked,

I understand how a bubbler works, the problem is to regulate the airflow to some suitable very low known value, as the remote pipe end (down the well) cannot be seen.

The idea was to place a small water chamber fitted with a window into the main air supply line. Air enters this chamber, and air leaves it, but the flow should create identical bubbles in the water chamber as it does at the base of the well. You can then just twiddle your flow control needle valve to get the desired rate of bubbling.

I feel that the system absolutely must bubble to work properly. A static "pumped up once" system will gradually depressurize and water will slowly climb back up the tube.  If the open end is sitting in silt or mud, it will very easily block. The bubbles keep the end open, and keep the point of measured hydrodynamic pressure right at the end of the pipe. That is vital.

If this is not done, when the well empties, the high pressure air stored in the pipe will all escape. When the well fills up, the water will climb back up the pipe as all the stored pressure has been lost.  You will not then be measuring the true water height.  It is vitally important that the whole pipe length remains completely filled with air. But the pressure will vary up and down with water level.  A source of replacement air will always be required whenever the water in the well rises, or a true depth measurement will simply not be possible.  

RE: Depth of water sensing

alternety

It will be necessary to force enough air into the pipe to bubble out the bottom as that is the only way you can be sure the pipe is full of air, meaning the air pressure now balances the water pressure.  Who cares how many bubbles come out the bottom, just as long as some do.

That pressure gauge is a calibrated temperature compensated bridge, 0-500 psi = 0-100mV out.  It has 4 pins to solder into a circuit board or directly to 4 small wires.  Power it from regulated 10VDC and read it directly on a high impedance DVM or data-logger on a 0-100mV input (54mV = 500ft) or amplified by a simple differential amplifier to 1V or 10V.

http://rocky.digikey.com/WebLib/Sensym/Web%20Data/19C%20Series.pdf

RE: Depth of water sensing

(OP)
I do not understand why the tube needs a constant supply of bubbles. Please explain where my thinking goes astray.

If you seal the top end of the tube and drop the other end into the water, water will enter the tube until the pressure of the compressed air just balances the water pressure.  The pressure of the air at this point should represent the weight of the water column + 1 atmosphere.

The air/water interface in the tube is quite small and air disolving in the water should be a very slow process so accuracy ought to be stable for quite some time.

If the well level goes below the tube it will simply resume operating when the level rises again.

Doing it by pressurising the tubing after installation would reach the same end state after starting with a tube containing only air.  As the water goes down the bottom of the tube bleeds air to maintain proper pressure.

RE: Depth of water sensing

When you seal the pipe at the top the air pressure will be the water pressure at the water depth in the pipe.  If the water rises up the pipe then it reads a lower pressure.  Only when the pipe is full of air does the air pressure equal the water pressure at the bottom.

RE: Depth of water sensing

Warpspeed thanks for the description. That is a clever idea rather like a hash water pipe or something.  So the pressurizing air enters the system at the bottom of your little sight tank. The bubble shoots up past the little window interupting an LED/detector.  Feedback the bubbles/sec to a valve controller and you'd have it.  Now about the algae on the window.. :) Heck the tank could have Chlorine in it; no algae.  I like that.

alternety; I think you are confusing a mercury or h2o barometer with what you are doing.  In that case the tube would be filled with h20 sealed then upended. The water column would drop to where the vacuum matched the weight of the h2o still in it.

 In the well case that doesn't work. Just as Warp and Brian are saying. If you had enough air pressure to force out all the water when the water column is highest, as the well is drawn down the trapped air will be under reduced pressure.

  It will expand and lots of it will bubble out. Now the water column rises again.  There isn't the original amount of air in the column.  So now water rises up the tube.  For every inch that rises up that tube your measured depth will now be off 1 inch.  This doesn't bode well for pump control... :{

RE: Depth of water sensing

A bubble sight tank will need to handle 200psi safely, so glass may not be ideal. Thick wall clear acrylic tubing may be better, and it is very easy stuff to work with.

Entering air could be via a small bore J pipe with the lower end submerged. Some bleach in the water will kill the nasties. Lots of fairly simple ways to do this.

RE: Depth of water sensing

(OP)
I unserstand what you are saying itsmoked. I had indeed thought of a barometer at one point - but incorrectly.

A sensor seems a better alternative.  I will put the low water assembly down now and do sensor later. I need to get the well safe now.

With my new understanding I would need to fool with continuous compressed air to make a surface sensor work and the submersible ones are two expensive.  Maybe I dould seal something like the one brianr referenced and drop into the well.  Or I could put something with a flexable membrane at the down hole end, presurize it, and put the sensor up top.

Thanks everyone for this discussion. It has kept me from going off hunting wild geese.

RE: Depth of water sensing

My pleasure alternety!

   If you really have to go "cheap" then dhwilliams solution really is the best.  It is far, far, far, simpler and nearly fool proof to the bubbler.  It is also cool!  As you could actually watch the "signal" ,as it were, with your own eyes.  I would simply hang a stainless steel rod for the weight and a ballasted cylindrical plastic float, (to keep it pointed vertically like a bouy).  Use monofilament fishing line with 7 or 8 times the breaking strength you need. It would be small and slippery, not caring if it touched the sides.  Get the whole thing working using a five gallon pail or maybe something deeper (a lake) then when satisfied replace the the monofilament with the correct length. Lower the float down the well followed by the weight.  It would work well.

RE: Depth of water sensing

How about infrared distance sensing to a platform floating on top of the water.

RE: Depth of water sensing

Yashu; hard to have a platform target floating on the surface when the surface is only a 6" dia with a violently wiggling pipe somewhere in it.


Hey alternety; I have another idea!  Maybe someone can poke a hole in it.

Take a SlowSyn stepper motor.  You feed them 120Vac and they just turn with huge amounts of torque.  They generally turn at a leisurely 72RPM.  You take a slender weighted bouy as mentioned before. Use the same monofilament line.

Set up two microswitches and a small little jig.  Set the jig up so as the water drops the line tension increases. When the line tension reaches a certain point of tension the related microswitch turns on the motor in the lowering direction until the tension drops and the switch opens.

  As the water rises the line gets more and more slack. When the line reaches a certain slackness the other switch closes. This runs the motor in the other direction winding up the line.  The line is on a spool so only one side goes down hole.  You just need to keep track of the turns of the spool to accurately know the depth.

   Now is that not brillant?!?

RE: Depth of water sensing

The simplest solution goes back to the beginning of the thread.  Attached a suitable pressure sensor to a weight, add a long shielded cable, seal it up and toss it in.  Obviously the pressure at the bottom of the well is a function of depth.

Ultrasonic pinging from the well cap to the surface of the water is a close second.  The only reason that this technique is on the short list is because there are off-the-shelf modules that would make it a relatively simple project.

RE: Depth of water sensing

Just a thought:

How straight are boreholes typically? Straight enough to use a laser sensor to detect the water surface? Nothing in the hole to go wrong, although I imagine initial alignment would be tricky.

I think the ultrasonics would suffer from multipath reflection problems because of the small diameter of the borehole compared to its length.

----------------------------------

If we learn from our mistakes,
I'm getting a great education!

RE: Depth of water sensing

The problem with a lot of these ideas is the power cable and pipe already snaking down the well. That will be moving around quite a lot and tend to cause problems with optical or acoustic systems reflecting back off the water surface.

Could the displaced air be measured ?  As the water column rises and falls, so air must move out and into, the top of the well. It would not give absolute depth, but it may reliably track changes ??

Commercial gas meters measure flow very accurately at low pressure drop, but I am not sure if they are bi-directional. If they are, maybe the little dials that show cubic feet of gas may be useful.

I really don't know, but maybe someone else can come up with a better way to accurately measure air volume flow in two directions. That would have the considerable advantage of not needing anything to go down the well that might tangle, jam, or drop off. Six hundred feet is a very long way down.

RE: Depth of water sensing

  The air volume method, ugh, very tough, I would think. And lack of the absolute would leave you/system always wondering.

  How about microwave?  Water is a MAJOR difference to well casing and plastic. I would expect you would get a very strong return from the water surface that could easily be wrung out from the rest of the returns. (Radar)

  One of my college profs helped some students make a radar for mapping below sand. They took it to Egypt to hunt buried pyramids because it could tell the difference between sand and stone at depth.

RE: Depth of water sensing

(OP)
Right now I have bigger problems.  I tried to put the low water sensor down today.

Short result - probe is stuck at about 100'.  Won't go up, won't go down.

Ask me if I am amused.

RE: Depth of water sensing

My understanding is that you want to be reliably monitoring your well on a regular basis to see how the water level moves vs the water being pumped and the various times of the year, without yourself operating pumps and takling measurements.  With a water column of 500 ft, nothing is easy.  You may want to speak with the places that sell geotechnical sensors, like Roctest or Geokon.  They call them borehole piezometers I think.  They are rugged.  These things are built with the wiring sealed into them.  I'm pretty sure that they  have excess stocks that they can sell at a reasonable price.  Then all you need is an interface for a computer to read the output of the piezometer.  In case of problem, you will not question the quality of your setup instad of the water pump or the capacity of the well itself.

RE: Depth of water sensing

Are you amused?  heheh.

I have delt with wells before.. And the sickening feeling when something won't come back up.  My old boss's well, about 2 months after an earthquake we tried to pull the pump for service. Nothing doin. We used a winch on a truck and it lifted the truck.

The only thing I can recommend is that when a pump starts the riser generally whips all over the place. Perhaps a few starts while jimmying will get the job done... Otherwise it's cheapo TV camera on a cable.  Don't get it stuck too. :0

What do you mean by "low water" sensor?

By the way do you have a flexible riser?  Just pull the whole dang mess with a winch from 500 ft away. Tie the sensor to the pump where you want it and chuck it(er.. lower gently) back down.  If you have rigid pipe..... Go fish.

RE: Depth of water sensing

Hehehe, you have the well, tried making a wish ?

Sorry alternatey, I could not resist.

Itsmoked is right, putting anything down there is going to be a big drama. Maybe I am paranoid, but the thought of having a "sealed for life" pressure transducer down a big hole just seems like an unnatural act.

How about hauling up your pump (a very big job) and fitting both a pressure transducer plus wire, and a bubbler pipe with plastic cable ties to the pump cable, and sending the whole lot back down. If the transducer works, the problem will be solved. If it craps out, there is nothing (??) that can really go seriously wrong with a bubbler.

RE: Depth of water sensing

(OP)
Remember - just because you are paranoid does not mean they are not out to get you.

Low water sensor - that device which detects that the water level is about to become lower than the pump inlet thereby causing catastrophic destruction of the pump.

Pump is on the end of 500' of solid plastic pipe.

Many $thousands to pull pump assuming a will drilling rig can actually get to the hole.  The well was drilled before the house.  Spouse and previous owner required dowser vs where I wanted it.  Dowser said drill here and in some reasonable depth (I think around 100') you will get limitless water.  Result - 605' no water and too close to house.

There are things to be said for city water (don't go there - not available and will not be).

My day has not been good.

RE: Depth of water sensing

I seem to remember an IC device which can measure VSWR on a bare wire immersed in water to determine the height of immersion. It used some kind of AC signal to avoid buildup of corrosion. I think it was from National semiconductor.

RE: Depth of water sensing

Still like the BrianR technique.

Simple enough. Then, put "an inlet" valve at the top and crank in air every day or so from a meaty pump to make sure the pipe stays full of air and combat the leaks.

RE: Depth of water sensing

So the pump pipe is rigid? Oh dear, I thought it may have been something that could be hauled out for maintenance.

It may not be very helpful, but another idea has just occurred to me. One way to measure the displaced air would be a counterweighted gas bell. As the well falls, air would be drawn in and the gas bell would sink in it's pond. As the well rises the air floats the bell higher.

If the weight of the actual chamber is counterweighted the pressure inside could be made extremely close to atmospheric, so it would have no real natural tendency to leak.

All rather primitive I know, and it would be huge, but again it has the simple virtue that nothing need go down the actual hole. You would just need a large open ended tank with similar total volume to your well, and a large water filled pit in which to float it. To measure well height you just need to look out of the window. It could even be built right over the well head ?

I get ideas like this all the time, I cannot help it. One day they will come for me.

RE: Depth of water sensing

(OP)
warpspeed - I know what you mean about the ideas.  I find that a couple of large gin and tonics can reduce the volume of the voices (or at least make them seem more reasonable).  I also understand there are muchrooms that can reduce or increase the voices; depending on the base state.

There are a real interesting bunch of ideas in this thread.  It really has been quite interesting. Anyone that can get the damn probe out of my well will get all the beer he or she can hold.  Once you have stepped away from the well of course.

RE: Depth of water sensing

Keep an eye out the window....

RE: Depth of water sensing

alternety; are you telling me you glued length after length of plastic together?

If you used continuos pipe off a roll then I can't see why you can't just pull the pipe out over a roller in one smooth continuous pull in about 10 minutes... Heck, I'd pull that pump every couple of weeks just for fun!

RE: Depth of water sensing

alternately,
this has been a very interesting topic although some of the ideas have bordered on silly, in light of the original concept of simplicity and low cost.  What is the implication of abandoning the stuff jammed in the pipe?  

At one stage I wondered about using one of those laser distance measuring devices but thought cost might cut it out.

I am convinced though that the best solution is a waterproof pressure sensor with moulded cable dropped to the bottom.  No compressor needed and no pipe.

2nd best is measure the air pressure in the pipe and blow air in until the pressure no longer increases, meaning bubbles are now coming out the bottom.  Use pressure < 2psi (50" water) to signal pump off.  This needs a 250psi air compressor and pipe proof to that pressure as well.


RE: Depth of water sensing

(OP)
The implication of abandoning the stuff in the pipe is I can't use the well.  The house is unlivable.  Given the problem I have had getting a realtively small device down the hole, anything else is probably not feasable.  Getting the probe down did not work at all well even before it got stuck. Either the pipe and/or bore hole are not straight or the power wire is all over the place. I might be able to do something with a solid pipe but it would immediatly go beyond what I can do by hand (too heavy).  I suspect the sensor is caught in a piece of the power wire going to the pump.  It is the only thing down there I can think of that could so this.

I agree about the pressure sensor.  A tube with a bladder on the bottom might also work.  This keeps the electronics on the surface.

I am going to look at doing something to use the original sensor to sense low water.  It used a current between a probe just above the pump and the pump body to determine if the well was empty.  The new well controller does not work with the old sensor although the vendor claims it is backward compatible.  The only alternative to this is to pull the pump and fix everything.

Right now I am really in a world of hurt.  It is way to dangerous to pump without a low water sensor.

I have many other really pressing issues with getting the house finished and I really don't need this.

RE: Depth of water sensing

Present headache aside. My condolences. I have another suggestion for depth monitoring.

Besides a correctly tie wrapped every 5ft, submersible 4-20mA pressure transducer for $359 plus $1.50/foot for factory installed vented waterproof cable that is.

If your pump pumps with a free head.  Another words into the top of an atmospherically vented tank the head is fixed.

The amount the pump can produce is directly related to the water column height.  This means you can use a flowmeter at the tank and monitor the flow to give you the water depth in the well.  You can zero it by monitoring the flow and running the pump until the water drops down to the pump and the pump goes dry which won't hurt it if you stop it the instant you notice the first slug.

RE: Depth of water sensing

That may not work if the pump is a screw type with a constant Rpm and displacement. But motor current may well  be reliable variable because the pump has to make up the height difference between water level and well head. This idea has already been proposed by "adc" in a previous post, and it probably deserves some further investigation.

I still think that actually getting anything down the well will be problematic, and that includes optical, acoustic or microwave pinging of the water. It looks like the existing pipe wanders all over the place effectively blocking the hole. That also probably rules out floats and counterweights mounted on wires.

RE: Depth of water sensing

Warp; they use positive displacement pumps down private wells?? I thought they were ALL multistage centrificals.

I could see the current having a nonlinear aspect.  But maybe not.

RE: Depth of water sensing

In the old days, miners took canaries into the mines to warn of "poison gas" build ups.
If the bird stopped singing: run.

So (providing you can unblock the pipe) you need a little cage, a canary, and a long length of string marked off every foot or so.

Lower the canary down. When it stops singing: voila! water!

(Reduce costs: don't buy a new canary every day: buy a few breeding pairs and you get a limitless supply)


Any joy getting the stuck sensor out?
I know the feeling when something gets wedged where it shouldn't and you just can't shift it. Not nice.
And how often is it that it that it would only need the tiniest push in a different direction to free up, but you just can't reach it to  do that?

Let us know how you get on. Sorry I can't offer any actually good advice.

"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams

RE: Depth of water sensing

Don't really know, but either flow or motor current must change, because the required amount of work changes.

Either one or the other must surely give enough variation to be a useful, if not highly accurate indicator.

RE: Depth of water sensing

See that's where I'm having trouble because I think the work stays almost constant.  What will happen as the standing water column drops and the pump has to pump the water farther up, the amount of water will drop, (flow) to keep the work, (motor-hp) the same. So the current will just sit there at the motor rated current.

RE: Depth of water sensing

Try to imagine if the well fills to within one inch of the top of the well casing, almost no work needs to be done to get massive flow.

If the well is pumped almost down to the 600 foot level, water need to be forced up through every one of those six hundred feet.

What actually happens depends on the type of pump, but the actual drive power requirement will change rather a lot I would expect.

RE: Depth of water sensing

I think that it is all very easy (if we can forget about the stuck things - I know, not easy to forget).

Motor current is not a good measure of water level, but motor power is. Power can be measured quite easily with a kW/current loop converter, which is a standard device and not very expensive.

Depending on pump curve, the flow goes back more or less when head increases. But a situation where flow times head (i.e. power) stays constant is not likely. The problem is that one has to measure a rather tiny change on top of a high power level. So secondary effects like mains voltage fluctuations and water temperature may disturb the measurements more than one can accept.

But, with a sufficiently fast measurement, it should be possible to indicate dry running and turn the motor off very quickly (40 - 50 milliseconds). Dry running will dramatically lower the power taken by the motor and it will be a very reliable indicator. Since dry running doesn't happen instantly, but gradually, and probably never with a completely dry pump (water will fall back into the pump and "grease" it because of bad pumping action and high water head) you will have the best of many worlds: reliable level indication, nothing to put down the hole, no risk of dry running the motor, level sensing always on same level as motor. You will also have a good indicator of water level since pump power can be read from the 4-20 mA signal and there is a corresponance (probably not completely linear, but monotonic) between head and power.

I will remeber your stuck sensor in my prayers.
 

Gunnar Englund
www.gke.org

RE: Depth of water sensing

Yeah, one beady eye focused on the amp meter, and the other beady eye focused on the flowmeter, and do some tests at midnight during the next full moon.

RE: Depth of water sensing

(OP)
It was still stuck when I left last night. I did run the pump, I need some water, but the type of pump it is has almost no vibration and there is no starting twist.  It has controlled power ramp-up (i.e., soft start).

It is a positive displacement pump.  It is a steel screw in a rubber casing.  There is a check valve above the pump.  Water won't run back.  The bearings and pump all use water to lubricate.

Current is a reasonable indicator and I have some curves from the manufacturer.  The controler holds the 32 VAC three phase fairly constant and the curent varies if I remember correctly. I was going to monitor this eventually ((after I live there).  I wanted an independent sensor that can read while the pump is not running to see rate of recharge.

RE: Depth of water sensing

(OP)
The well is healed.  The secret was the sacrifice of a small mammal behind the well head at midnight.

Here is what really happened.  The probe is still stuck and will be abandoned in place.  I talked to the pump manufacturer again and tech support said there were many of these controlers that work OK with the old probe.  Told me what wires to attach.  I told him that that is the way I did it before.  So, just for jollies I reconnected the old sensor.  Did not work.

I put a meter on the probe terminals to see what the voltage looked like and it was strange.  Reversed my  probes and the voltage changed.  There was some AC on the line.  Thought - ground current; but from where.

When I initially installed the system a couple of years ago with the old controller it would trip the GFI breaker whenever it turned on.  I fixed this by isolating utility ground from the system ground at the power supply.  That fixed it.  FIgured I would do it the right way at final install where a GFI would not be required.

Today I poked around with the meter trying to find the source and saw a noticable potential between the two grounds.  Connected the chassis ground back to the utility ground and presto - it works.  I just spent about $350 and many hours I do not have to spare trying to replace the sensor when all it needed was that wire.

@&@)(&@$&@%)@!_+_)%$#(*&&*#

I will address the depth sensing at a later time.  I have really appreciated the thoughts and ideas you guys have contributed here.  It has been incredibly helpful.

RE: Depth of water sensing

Very relieved to hear things are finally going your way.

RE: Depth of water sensing

No permit shall be issued unless and until the following water source requirements are established as prescribed in Section 7.73.060:

B. August through October. For each connection to a well water source, a minimum of two gallons per minute of yield must be sustained during a twenty-four hour period of continuous pumping, or until two thousand eight hundred eighty gallons have been achieved during a time period of twenty-four hours or less of continuous pumping.

So your 2 gallons/minute doesn't sound to bad to me.

RE: Depth of water sensing

(OP)
3 actually. I have almost a gusher.

RE: Depth of water sensing

Can't it just be simple...

put a 'water sensor' at a low mark location... and another at a high mark location...

if water get's to the hi mark... pump out well until low mark...

bottom of well water detector provides a failsafe for the pump

KISS

RE: Depth of water sensing

Yashu this well is 500 feet deep with the pump already installed.  NOTHING IS EASY about it.

RE: Depth of water sensing

"the sacrifice of a small mammal behind the well head at midnight"

Not the cat, I hope?

Gunnar Englund
www.gke.org

RE: Depth of water sensing

I can offer a suitable cat if required. I'm sure my wife won't notice...

----------------------------------

If we learn from our mistakes,
I'm getting a great education!

RE: Depth of water sensing

My 300-foot deep drilled well is simply equipped with the usual $30 pressure switch - the sort the turns the pump on when the pressure drops to 30 PSI and turns the pump off when the pressure reaches 50 PSI.

Safety feature: If by chance the well is pumped dry (two hoses plus several hours, maybe...), then when the pressure drops below about 15 PSI then the switch turns off totally and must be manually reset.

I didn't think that anything more complicated than that was 'required'.  I understand that it would be 'interesting' to track the depth of the water in the well - interesting like watching paint dry after about the first week.

2 or 3 gallons a minute is around 3,600 +/- gallons a day.  That amount is probably almost enough for a laundromat (but not quite).  Get a big pressure tank to reduce pump cycle and make it easier for your well to have time to recover.

We should rename this thread to 'Depth of Message Thread Sensing'.

By the way - calculate the pressure in the pipe near the pump (at 500 feet down?) when the water level drops to almost that level (this is the worst case).  Compare this pressure to the pressure rating of the pipe. It can be amusing.

RE: Depth of water sensing

Amusing? Like when our fire crew layed 1.3 miles of fire hose that ran down slope 1,500+ feet?

93! posts must be some sort of record!!

RE: Depth of water sensing

(OP)
94

I realize this thread has too many posts to keep the objective in focus.  Brief summary:

Two problems.

1 - Track water level to determine how the well is performing.  Track recharge rate and static level. Unproven well capacity.  That is what most of the discussion is about.

2 - Protect the pump from running dry.  This pump can not be protected by sensing dry running after the fact. Everything is water lubricated.  No water = no pump.

Other - pressure is around 200 PSI.  Pipe is fine.  Lava would upset the whole thing.

RE: Depth of water sensing

There are millions of drilled well pumps using nothing more complicated than the normal 30/50 PSI pressure switch that I've already described (with the ~15 PSI cut-off).

Nobody (at least virtually nobody) is using water depth info to control their drilled well pump.  This thread clearly demonstrates why nobody is doing so...

In my case, for various reasons having to do with freshening up the water quallity once in a while (over about 16 years or so), I've purposely emptied my 300' drilled well many times.  Several times per year x 16-odd years = about 50-ish.  Never a problem (knock on wood).

The pump doesn't really run dry. It starts sucking air while sloshing around in the last remaining inches of water. As soon as it does so, the pressure switch at the top end will shut it down within mere seconds.  Then within a few more seconds it will be submerged again (2 or 3 gallons a minutes coming in, takes less than a minute to submerge it again).

Obviously, surviving the inevitable dry well must be a fundamental performance and reliability requirement for the pump designer.

I expect that most pumps die of old age (something corrodes or cracks due to age or exposure to the environment) long before some occasional mild abuse would do them in.

There must be a half-dozen guys (engineers, technicians) at work that are interested in knowing their well depth.  Not one has ever implemented anything.

It would be a big market...

RE: Depth of water sensing

500 feet is (as you wrote) about 230 PSI. That depth and pressure is slightly beyond the normal.  Hopefully your well installer has selected the appropriate spec'd pipe.

One of my well pump bidders (many years ago) specified 100 PSI pipe for my 300 foot well (up to 144 PSI). He also specified wire that would have had too much voltage drop. He didn't get the job.

This reminds me of a joke - if you're lost in the woods in Canada, then simply pick up a chainsaw, axe, or hachet and start cutting down a tree. Within seconds, some plaid-clad lumberjack type will appear from nowhere to show you what you're doing wrong.

If you're lost at sea, just start to tie a knot in a rope.  That's it - instant rescue. Within seconds, "No no no no, that's not the right type of knot..."

I guess wells are the same thing.

PS - If you're lost in the Phillipine jungle, then you put your underwear on your head. Within seconds, "Hey Joe, you know that your underwear is on your head?"

RE: Depth of water sensing

97!  Who  w i l l   b e   1  0  0 ?

1) Unless you are a well, hobbyist, addict (like I might admit to), as VE1BLL correctly points out: caring about the wells performance/recharge rate will be as exciting as watching grass grow or more directly; a puddle evaporate.  You will find out the well performance/capability soon enough and it will be fine or you will need to make changes(no baths on alternate months).

  Frankly if you are running a tank as is required most everywhere, for how else do you provide the 1,500 gallons of fire fighting water most places demand, then it will be no problem to keep that thing full unless a dairy is involved.  You are providing a tank? Tell me you have a tank.  A nice 2,000 gallon one... Or two.. The guy next to me put in two 5,000 tanks side by side to support his private one person observatory bathroom, (the only thing on the site.

2) You can easily see if the pump is going dry by watching the discharge pressure.  I don't care if that pump is made out of pumice spinning in cotton bearings, it's not going to lunch itself in 1.00 seconds while it starts to suck a little air/water mix.  You are being overly paranoid. Yes you would not want it to go on and on nor occur at the end of every pump cycle but a few calibration gurgles is not a problem.  If you are convinced it is a problem then you must buy the $1,115 plus submersible sensor noted above and some electronics and monitor the well performance and turn off the pump too while your at it.

As I continue to beat this horse,(now into a red pulpy goo), Here's-what-I-would-do: :)

1) Put up a storage tank if you don't have one. This drops the panic factor when working on the well as you have a few days of reserve on hand.

2) Put up a storage tank as this is much better for the down hole pump to not cycle constantly.  It also allows a current or flow monitoring if desired.

3) Run the down hole pump with a float switch.

4) Run a second three phase pump with a VFD (single phase input) into a small pressure tank. Use pressure sensor feedback to exactly control this three phase pump to maintain the perfect house pressure. No on/off, on/off, garbage when some faucet-garden hose combination causes maximum pump cycling.

And spend, spend, spend as it's all justifiable. One must have a nice well after all.

RE: Depth of water sensing

Without actually knowing for sure, I would guess that the pump itself would probably have some sort of float switch that would shut off the juice before the water level fell below the pump intake or motor/bearings.

It is probably a fairly simple, reliable fail safe system, otherwise the pump manufacturer would most likely have been sued into bankruptcy a very long time ago.

If you can plot motor current, or well flow, versus water depth, that could then be used to automate pump cycling without relying on the safety cut out.

RE: Depth of water sensing

(OP)
Guys, you are debating this with the wrong person.  I am paranoid, but not specifically about the pump.  This is not your father's pump that you and your neighbors have used for however many years.

The pump uses a steel on rubber interface that tends to melt fairly quickly without lubricant (i.e., water), and lock the rotor.  It is not a centrifigual or piston pump.

The pump motor uses fluid bearings.  The fluid is ,wait for it, water.  How long do fluid bearings work without fluid - a minute or so?  I don't know, but I suspect not.  Nor do I wish to collect experimental data.

The pump manufacturer specifies, and supplies, a protection device so that the pump will never ever pump dry. This device is installed.

The warranty is void if damage occurs to the pump because of dry pumping.

Please drop this aspect.  It is unproductive.  You want to argue - buy one and experiment.

The tracking.  Yes I can do a number of things.  We are going to be doing a lot of gardening.  We have 5 acres.  The well is in solid rock with unknown sources of water.  There are no alternate water sources.  A shallow well on the property goes dry in the summer (shallow meaning it goes to bedrock).  There are drought conditions that come and go.  Salt water infusion is an issue here.

The configuration - well pump (about 32V 3 phase AC), low water protection sensor. This pump will be controlled by a float switch in a 1500 gallon storage tank.  Storage tank feeds a 1.5 HP DC variable speed pump (25 GPM max) that pressurizes the house system.  This pump will be protected by a float valve in the storage tank (it is a multi-stage centrifigal, but the manufacturer does not look favorably on dry running either) and controlled by the normal system pressure switch.  Bladder pressure tanks and a 0.04 micron water filter complete the system.  Well, an RO unit to take arsenic out of the drinking water is also included.

Believe me - I would not be doing anything I did not consider (based on manufacturer recommendations/requirements) necessary.  It costs money, grief, and time I do not have.  Please put these issues to rest.

RE: Depth of water sensing

100! BOO_YAH!

RE: Depth of water sensing

Well, oh....kay... sheesh.

Sounds like a nice system overall.  About what I'd do.  I thought 32V 3-phase was just some sort of psychotic spasm of the pen by a paranoid... :) but you keep doing it, which makes me start to believe it.  Why is it 32V?  Are you off the grid?

What brand is it? I'd like to read about it.

RE: Depth of water sensing

(OP)
The system is actually designed to run from 48 VDC solar panels. I built a DC power supply to replace the panels.  The reason for using the pump is power consumption and robust design.  The most I have measured as pump input is about 500W.  This is not exhaustive monitoring but anecdotal.

The pump is made by Lorentz in Germany.  Importer is http://www.conergy.us/DesktopDefault.aspx.  It was the most interesting and energy efficient pump I could find. Have fun.  You should see my heating system .

RE: Depth of water sensing

Hahah heating.. probably needs water? DOH!

Thanks for info.  Next question: What state are u in?

Hey did you see this Circuit Cellar contest winner?

http://www.circuitcellar.com/psoc2004/winners/c2982.htm

 It said solar and three-phase.  I scratched my head but I bet it's for one of your pumps after realizing the low volatage.

RE: Depth of water sensing

Hold it!

Someone is pulling a lot of legs here.

I do not accuse you, alternety. But I do question your sanity.

A motor cable being 500 ft is bad news even if you were using a higher voltage. With 32 V it should be a catastrophe with voltage drops in the 50 percent range if you do not use a cable as thick as an arm (and a leg - I would like to add). What gauge is you cable? No wonder things get stuck in the bore.

Otherwise, this has been a very fun and instructive thread that we can learn a lot from. It has also produced some very good little essays that, no doubt, will be engineering classics in the future.

Now, who will post #200?

Gunnar Englund
www.gke.org

RE: Depth of water sensing

Hmmm,

500 watts at 32 volts is 15.625 amps total.  Distributed over three phases is only five and a bit amps per phase. That is not a huge amount of current.

Let's allow for 5% resistive cable loss (15% total) in each phase at 5.2 amps, that is a voltage drop of around 1.6 volts per leg. Maybe 0.3 ohms per phase at full load.

Suppose we specified 10mm squared capacity cable (nominal 50 amp rating) that would allow for a cale length of around 174 metres. Rather more copper than that would be desirable, but I just wanted to get a feel for the figures.

If the motor power unit had remote voltage sensing, it would be theoretically possible to fully compensate for any reasonable voltage drop by automatically increasing the source voltage at the three phase inverter. Certainly possible, and if I was designing a deep well pump power supply that is probably how I would do it.

Engineering can be fun.  Was it a black cat ?

RE: Depth of water sensing

A 500-watt pump for a 500-foot well? - geesh.  Why bother saving power on something that should have an ON duty cycle of much less than 1%. If you're on the grid, then you've spent a lot of extra money to save maybe $5 per year.

32-volt 3-phase?  WHAT?  'Oh one more thing I forgot to mention is that the well is on Mars where the gravity is slightly lower.'  

Personally, I've got to get back to monitoring the cathode voltage on my TV set.  Everyone needs a hobby...

RE: Depth of water sensing

(OP)
I am in Washington on an island about halfway between Seattle and Canada.

Yes the heating needs water.  The system has been sitting waiting to get filled for many months until I could find a way to get rid of the suspended solids in the well (the pump and assorted things I have put down there are not considered suspended solids).

The wire is #6 copper.

One aspect of the pump is that is does not have huge turn-on spikes.  It is soft start. This makes it easier (read cheaper) to configure a backup generator for the house.  It also lessens the possibility of breaking the PVC pipe from starting torque.  Such things happen with centrifigual pumps.  Except for needing water, it is also a quite robust system and should yield good equipment life. This type of pump head design is I believe used in things like oil wells with dirty materials.

I saw that Circuit Cellar article and had the same thought. The circuit board does not look quite the same as the one in my controller and I don't know who actaully makes the controller.  The CC design appears to be for a higher motor voltage.  That would make the wire much less of a factor.  I really don't know why my controller was designed for low motor voltage. Possibly a mind set about solar power being low voltage. Maybe component issues when they first made these things and they stuck with it for backward compatability to the pump motors in the ground. The guys selling the pump do not have any info on the internal circuits.  Their vendor considers them proprietary.

With a lot of plants to water the pump will probably run a good bit.  Compare the pumping efficiency and power consumption with the 1-2 HP centrifigual pumps that would be the alternative.  And some of the better ones of those actually put the electronics down the hole in the pump body.  That feels way dumb.

My wife has also been known to have some nagging questions about my sanity. But she appreciates having a pet engineer on duty anyway.

Black is traditional.  Calico yields spotty results.

If it will be of any assistance, the way I usually monitor my monitors is to add a custom coil to the neck of the CRT. I have a detector focused on the screen with video analysis software that can track and measure an individual video dot.  By using a half frame every so often with a known magnetic field applied I can calculate the anode voltage from the deflection distance of the electron beam.  It is fast enough that a normal viewer does not see the stolen field.

RE: Depth of water sensing

alternety you and your well are a classic.

On my next yacht delivery I'll drop by.

RE: Depth of water sensing

Even with 100 percent efficiency and no friction in the tubing (working against static head only) a modest flow rate of 1 litre/second would demand about 1500 W shaft power and that would be something like 27 A at PF=1 and 34 A at PF=0.8

A #6 wire has abt 13 mm2 area and will have a voltage drop of around 6.7 V/phase or 11.6 V measured between phases.

I have never seen a pump with 100 percent efficiency, so either you have measured when the water level was quite high - or you have a flow much less than 1 l/sec. What does the nameplate of the pump motor say?

You have proven adequate sanity by telling us how to monitor electron flow in your CRT. Much appreciated. Sanity will not be questioned again. We are moving towards 200. Like it or not.

Gunnar Englund
www.gke.org

RE: Depth of water sensing

skogs... back in the olden days, (Post 7 of this script),
the dear,(paranoid), alternety stated 2 gallons per MINUTE.

Yes I blew right by that for the next 70 posts thinking 2 gallons per SECOND!

2 gallons per minute equals 0.126L per second. Near the proverbial "kidney rate".

I get 0.45Hp for the expected flow/head which matches rather well with 500W.

RE: Depth of water sensing

I was searching for flow information somewhere. But - as usual - I didn't see it when I was looking at it. OK, 500 W makes sense for 2 gallons/minute. I think...

There will probably still be enough controversial stuff in this thread to keep it going to 200 and beyond. Like dividing by three to get current in a three phase system. Or the ability of a PVC tubing to withstand about 200 PSI. Or if it is OK to steal your wife's cat to sacrifice behind the well-head. And much more.

Gunnar Englund
www.gke.org

RE: Depth of water sensing

I can see some logic in employing a three phase induction motor. It is the simplest system providing sufficient starting torque without requiring start/run capacitors or switched start windings. You can just pot the entire motor winding and entry cable, and it would then be a solid impervious lump.

The cylindrical rotor would then run wet inside the potted stator, a lovely simple reliable arrangement.

Three phase is also an efficient way of transferring power over lengthy cables, which is one reason it is used for the power grid instead of single phase.

Thinking about it, extremely fine wire in the motor windings and a very large number of turns may not be as reliable as fewer turns of much more robust wire. So for the ultimate in reliability a lower operating voltage may be a good thing. The only real down side is the once only cost of the supply feeder cable.

I would expect if motor efficiency were compared to cable transmission loss, the overall losses would be well balanced between the two. Sounds like a pretty good well thought out system to me.

RE: Depth of water sensing

skogs, my calculations were intended only as a very rough grossly oversimplified ball park estimate to get some sort of a handle on cable requirements.

Motor power is given in watts, not in volt/amps as it really should be for a reactive ac circuit. It was easier to just assume the current split three ways and accept that as the rather suspect basis. There is really insufficient information available to do it properly.

RE: Depth of water sensing

Okay... Are we thru here? Is there anything else alternety wants to discuss? Are there any questions pending? I hate to see this thread go... it has become like, an, old friend.

Perhaps we should start critiquing the heating system? (Which should have R.O. water and antifreeze mix in it!)

In closing I will present a runner up in the 24th annual San Jose State University Fiction Contest which highlights the literary achievement of 'most terrible sentences that take their inspiration from the writer Edward George Earl Bulwer-Lytton who started a novel with "It was a dark and stormy night."'

Ken Aclins, Grand Panjandrum Award:

"India that hangs like a wet washcloth from the towel rack of Asia, presented itself to Tex as he landed in Delhi (or was it Bombay?), as if it mattered because Tex finally had an idea to make his mark and fortune and that idea was a chain of steak houses to serve the millions and he wondered, as he deplaned down the steep, shiny, steel steps, why no one had thought of it before,"

RE: Depth of water sensing

The heating system is of vital significance and definitely requires in depth discussion and full engineering analysis and evaluation by this august Forum.

So fess up alternatey, what gives with the heating system ?

RE: Depth of water sensing

(OP)
Do we really want to do this?  It gets us further into the building project from Hell.

RE: Depth of water sensing

hahahaLOLOLololol.  Let me wipe my eyes. <sniff>

Only if you want alternety... There are some bright people around here if you want a critique or suggestions.

I was a technical analyst for the California Passive Solar Home Design contest.  We saw some real doozys.

RE: Depth of water sensing

118 - and counting...

Gunnar Englund
www.gke.org

RE: Depth of water sensing

(OP)
If there is anyone out there still waiting with bated breath to hear about the heating system; your reward is ready.

I am reopening this thread to see if the same guys are still monitoring.  The previous exchanges were both helpful and entertaining.

There is a problem.  For those of you supprised by this - there is a cloud of bad Karma surrounding me that makes my entire personal warped space a subset of Murphy's laws which, of course, underpin all known engineering principles.

The house has exposed concrete floors with embedded heatng tubes.  There are a large number of zones.  The reasons for the numnber of zones include personal living preferences, normally unused/unheated space, radically different loads (e.g., greenhouse, room with serious Southern glass).  The basement has fewer zones.  Upstairs (primary living space) has a floor with the following construction. Subfloor, 3" foam, 2" regular concrete.  Each zone has a thermal break between adjacent zones.

The boiler is a condensing 85K BTU variable firing rate unit.  There are about a half dozen controllers taking care of things.  Solar exposed slabs have embedded temperature sensors.  DHW (domestic hot water) is indirect and uses a well insulated tank heated by boiler water in a coil.  There is another tank in the system that acts as a buffer for the heating loops to prevent short cycling of the boiler when a small demand is made (e.g., one bathroom).  There is a dedicated loop to heat make-up air for the range hood.  This loop is controlled by a variable speed pump that senses temperature drop across the coil.

Now we get to the problem part.  Did you get a fresh beer? The "normal" way to pump the heating loops is to run a fairly large pump at full speed and provide a pressure bypass between the hot side and the cold side of the system.  As less heat is demanded, more hot water simply circulates in the system in the boiler room.  

My approach.  A variable speed pump replaces this primary pump.  A differential pressure sensor looks at the pressure across the pump and adjusts speed to just supply the water needed for heating demand.  The loops are generally of similar length and have flow adjustments available to balance flow at a given pressure.

The problem.  I finally installed (just a jerry rig for now) a filter to get rid of the < 0.25 micron crap in my well water.  Works just fine. I could now fill the heating system.  I did.  We made hot water last week.  The control systems are not active except for the previoulsy mentioned differential pressure controller.  Looked OK.  House got hot.  Tried turning off some hot water circuits.  Differential pressure does not remain constant.  Oops.

Read specs of equipment supplied by contractor (I know, I know - but the contractor is competent and I have many other problems).  He installed a pump controlled by a 0-10V input and a differential pressure sensor that provides a 0-10 V output.  The problem - it ain't a control loop.  There is no set point/feedback.  The pressure sensor is just that. A sensor.  No feedback loop. If differential pressure goes up, so does the pump speed (or down, there is a switch to reverse response and that is probably on).  It hits equilibrium, but there is no control that determines what that point of equilibrium will be.  It needs to be a specific water pressure (head, for the heating people).

I am Googling my little fingertips off to find a solution.  I need a system that controls the pump to reach a setable pressure point.  An ancillary issue is the noise of the variable speed circulating pump.  Based on the listing of a starting capacitor value, it is a SCR/TRIAC control of an AC motor rather than a brushless DC PWM motor.  It vibrates a lot. This seems like the wrong approach, but I don't have an alternative.  I would like to minimize throwing away expensive components but the solution needs to be one the inspector will not have a problem with. They like things built by other people and having standards compliance lables.  I can also leave it alone and fix it later.

OK.  If you are still out there, gnaw this bone to the nub like you did the last one.

RE: Depth of water sensing

Tear it all out and install some cheap electric baseboard heaters.  My house: 2800+ sq ft, 21 degrees C all day with setback to 18C at night, heating costs about Cdn$1.2k per year (varies slightly). Capital cost, maybe Cdn$500.

Aren't there some PLC type industrial controllers that can be interfaced to virtually anything and can be programmed to do virtually anything?  I believe that some even have some control loop support built-in (or maybe fuzzy logic).

Google 'PLC' to start.

RE: Depth of water sensing

Welcome back alternety ..our own private little New Orleans...


Well that system looks like the kind of nightmare I would want.
Its own technical entertainment.. (for life)

First with a system that complex, I am astounded that you filled it with "whatever water was lying around". If you don't replace that rot gut with distilled or deionized or at the very least R.O. water you are going to be very sorry down the road.

Next don't listen to VE1BLL. It's obvious he has never luxuriated upon a heated floor. aaaaaaah.

What exactly is your pump/speed controller?

RE: Depth of water sensing

"...never luxuriated upon a heated floor."

I used the money I saved with my cost efficient $500 heating system (vice $15k+) and bought something called 'fur-ni-ture' so I don't have to luxuriate directly on the floor.

!!!!

RE: Depth of water sensing

Wonderful to see you back here alternety, I felt rather guilty about pressuring you for details on the heating system. I can definitely identify with all of your problems ! I once worked on a large solar/hydronic heating system for a school here in Melbourne, hence my great interest in all this. It also had some rather interesting control problems.

First up, the control of flow will definitely require some sort of PID controller that can be tuned to suit the dynamics of your system. Motor speed may be one method of flow control, but another would be a motorised valve. We used a system like that with a two way valve to divert flow either around the main heating loop or bypass the constant speed circulating pump.

Buried floor heating is obviously going to be slow to respond because of the large thermal mass, fan coil units would offer much faster and tighter control of room temperature. The ideal system might be to use the floor heaters to provide minimal "background" heating, and switch fan coil units on and off in the occupied rooms.

 

RE: Depth of water sensing

I'm no heating specialist but I like this thread.  I'd be tempted to say to put an op-amp with a DC-offset potentiometer, to shift the feedback from the pressure sensor and provide a "thermostat" adjustment with a little hysterisis.  But my notions of a closed loop system are a bit fooled by your system description.

How do you relate the differential pressure to the desired temperature?  How will this single point of feedback ensure comfort everywhere in the house?

The flow adjustmetns for all of your loops, how do you control them?  And for all these rooms or loop segments, what is the desired temperature feedback signal?

RE: Depth of water sensing

felix; picture a pump running creating a pressure.  Now picture a manifold that the pump feeds.  The manifold has, say, 10 electric valves on it.  Each one feeds a ZONE or specific space requiring heating.  To control the temperature in a ZONE you locate a thermostat in each ZONE.  That! Is what controls the temperature.  All the zones feed back to the pump suction.

What alternety is dealing with is that the flow through the zones needs to remain at a certain rate.  Each zone has a valve that is adjusted to allow that specific flow WITH A FIXED HEAD PRESSURE.  Each time a zone goes on the head would change. If the pressure changes the flows change.  The standard "we don't care about electricity" solution is to run the pump against a relief valve that just bypasses everything over X pounds of pressure so that the zones always get the same flow because the head is constant.

  alternety wants to stop wasting electric power on running against a relief valve by instead running the motor only at the speed required to just maintain the head constant.

alternety can use just about any junk PID controller that puts out 0-10V to control the head.

Normally this would be pointless because the energy that is lost in the bypass valve immediately appears as heat in the water DOH! So what if some minuscule percentage of the water heating is electrical?  But if you are off the grid it could make an important difference.

RE: Depth of water sensing

Got it!  This control has nothing to do with the temp control itself.
Well, the rising energy costs might someday justify a mass production of such controls.

RE: Depth of water sensing

Interesting point Itsmoked, I had not really thought about reducing pumping power. We used a three phase induction motor direct coupled to a centrifugal pump, and direct pump speed control was not an option. The sort of ubiquitous plant room circulating pump used everywhere.

One concern I have is that boiler water flow will vary if it is in the main loop. When running at very light total load, the system flow will fall, and the boiler will short cycle. That may cause problems with large cyclic temperature variations in the boiler tubes.

A better way may be to use a pump bypass and keep boiler water flow high all the time, and also have sufficient stored water volume in the boiler circuit to minimize cyclic temperature fluctuations. Water flow through the load can then be cut right back.

Some sort of large insulated thermal storage tank would then enable the boiler to run for longer periods and shut off for longer periods. Short cycling of boilers is bad news for both wear and tear and efficiency. I doubt if circulating pump power will be a significant cost compared to original outlay and final running cost. It might be best to just let it run at normal speed continuously during the heating months. A duplicate backup pump might be a good idea too just in case...

RE: Depth of water sensing

Warp; You make a good point about short cycling boilers.  I know short cycling furnaces is bad...

But in alts 'heating' post he does point out a hot water storage tank for short cycling prevention. AND! He has a variable rate burner. That should permit longer lower energy cycles when needed.

Now let me ask: Is there such a thing as short cycling when referring to "condensing" burner systems??  I thought the problem with short cycling was because a burner system would end up not drying out and the sheet metal would then rust out.  Here we have a system designed to have water condensing out on the innards and running down the walls to a drain... The walls are Monel or SS.  Not going to rust out.  So why not short cycle?  Might be an efficiency issue?

RE: Depth of water sensing

(OP)
Sorry - I started this up again and then disappeared.  My computer has had problems and tonight we lost power.

Oh well.  itsmoked has saved me a bunch of typing.  Yes the zone control valves and individual zone flow adjustments control each loops flow.  An objective is to make each loop about the same length (read - pressure drop). The assumption is more or less constant pressure across the circuits (zones).

Re comfort.  A guy I am using to finish some things left behind by the latest builder when he went on to the next project came in after I had the boiler running for 2 days to purge air.  He said he told his wife that she really would have to experience how comfortabe the bulding was to believe it.

Short cycling is bad for most any mechanical equipment.  In a normal boiler or furnace it also causes significant losses up the flue as the unit heats, only to shut off and allow the residual heat in the core to dissapate.  Solution - low mass (i.e., not much water) boilers, forced draft combustion, and condensing temperatures.  In older boiler designs it was important to avoid condensing because the cold water return temperatures could actually damage (crack) the boiler.  Condensing boilers want to see return water temps low enough to condense all the flue gas water vapor components.  The heat of condensation (evaporation) released significantly improves efficiency.  My design water temp in the radiant heating loops is about 85 degrees F.  When the boiler is runing you can watch the water running out the condensate line. The flue gas temp was, I believe, less than 110 degrees.

Regarding the idea of "let the pump run all the time".  There are definate proponents of radiant systems that use constant circulation.  The idea is that it provides smoother heating response by adjusting temperature of the water more slowley. It is also supposed to eliminate noises from a sudden influx of hot water.  At 85 degrees I don't feel this is a superior solution.  And the pump energy costs just keep going on as well.  Granted not a big number but anything multiplied by 24X7 adds up eventaully.  The cost of the installed solution was not a whole lot more than the alternative.  Granted this costing left out the requisite controller. But I suspect it could have been done correctly for about what this has cost so far.

The Grundfos pump has also turned out to have what I consider excessive noise/vibration. It appears to be a conventional capacitor start motor with a Triac rather than a brushless DC motor.  I suspect that the DC approach would have reduced the noise.

Incidentially, the heat exchanger in this unit is aluminum.  All the nasty condensates go through this or plastic.  My sense from research is that the stainless steel exchangers do not seem to have a clear durability advantage for a number of reasons.  Lower conductivity/higher differential temp stress seems to be popular.  But there are well respected units using both core materials.

I do indeed have a buffer tank in the system to mitigate short cycling.  This equates to having a bunch of water in the boiler circuit but localizes it to an insulated tank. Some zones are quite small (e.g., a bathroom).  The boiler capacity is only 85 K BTU.  This is adequate for a design day with everything in the house heated to 70 degrees.  This is all the basement, the garages, the green house, and other areas normally not heated.  One bathroom is not much of a load.  When heat demand occurs, it circulates water from the buffer tank.  When the return water temp from the buffer tank drops low enough the boiler comes online and heats up the system water including the buffer tank.  The rate of heating is adjusted by varying the boiler firing rate.  I believe it can throttle down to 15 or 20K BTU.  Even this is way too much for a single zone.

The installed variable speed pump is a Grundfos 26-96.  The pressure sensor is an Alta Labs PWL 050. Both units can use either a 20ma or 10V interface. There is nothing here to actually set the pressure.  At full flow it reaches equilibrium at about the right pressure.  But if flow drops the pressure goes up.  The pressure sensor output goes up and the pump changes speed but there is no set point.  So it just reaches another equilibrium point but it has no real realtionship with the target pressure.

I believe a simple processor with an A/D input and a D/A output would fix this. I was hoping for something not terribly expensive that was pretty much setup to do this. I really don't have the time to screw with building one and bulding inspectors are really fond of things like UL labels.

I am going to peruse the ads in Circuit Cellar.  I am sure there are devices there that can do it but probably not with the necessary code.

RE: Depth of water sensing

Sounds pretty nice... I haven't had heat in my house for 5 years.. I'm drooling.  I just got a quote for a very simple system all in the attic.  I provide the flue and gas and electrical.. 6 ceiling registers one return. $7,963.00 Gesh!

I think I'm faced with doing it all myself, Groan.

alternety; Just get one of these:
http://www.omega.com/ppt/pptsc.asp?ref=CNI_Series&amp;Nav=a03

Most likely you'll want the CNi3253.  It has provisions for 0-100mV and 0-1V and 0-20mA one of those should work well for your pressure sensor.   It also outputs 0-10V.  You can then set up a very robust PI control (skip the D).  You will have a direct readout of the pressure differential. Would be very slick.

RE: Depth of water sensing

Agree completely with itsmoked, one of those PID controllers would be absolutely ideal. With the software auto-tune function, the proportional gain, and integral time constant will self adjust. The thing will learn what it has to do all by itself to hold a stable setpoint with optimum dynamics.

(Turn off the derivative action, it is not required).

It sounds like you have a very well designed and thought out heating system. Fortunately here in Melbourne the climate is very mild and minimal heating or airconditioning is required.  

RE: Depth of water sensing

More groaning... The idiots faxed me only the first page of the quote... The second page, (mailed to me), added $3,100 more.

I can feel that fiberglass now.

RE: Depth of water sensing

(OP)
itsmoked

If you have not had heat for 5 years it would not seem to be a pressing issue (Austraila, as I recollect, is big on wool - wearing not burning).  Can you tell us about your seasonal heating requirements, calculated heating requirements (i.e., heat loss calcualtions) and the cost of a BTU of energy from various fuels in your location?

Insulation may be a better alternative or at least part of the solution.  An additional shrimp on the barbie could provide the required BTUs and taste good.

RE: Depth of water sensing

alternety,

Looking at my natural gas bill for the last three months, my daily heating cost during mid winter was $US 1.72 per day for 190 Mj per day averaged.  That includes all heating, cooking, and hot water combined.

Electricity here in Melbourne is 10.1 c per Kwh for day tariff, and 5.4C per Kwh off peak night tariff.  Please note, these costs have already been converted into US dollars.

I have four individual window air-conditioners that are rarely used. A rough guess might be five days per year at ten hours per day. (we may have a heatwave for a few days only).

My home is very well insulated (by me), and has some passive features that reduce the summer cooling load, mainly shading by deciduous trees, and convective ventilation of the roof space. Being a mad inventive scrooge, I take all this fairly seriously.

RE: Depth of water sensing

What does the heating cost have to do with the deep water
sensing ? Anyone interested in discussing the price of the tea in China ?

<nbucska@pcperipherals DOT com> subj: eng-tips
read FAQ240-1032

RE: Depth of water sensing

nbucska; this post long ago morphed into a discussion about a complex heating system utilizing the the water that was sensed down the deep well.

alternety; Here's that info:

LOCATION:              Central Calif. coast, 10 blocks from Pacific Ocean.
COLDEST TEMP:          20F
DAYS BELOW 40F:        5/year
NIGHTS BELOW 40F:      30/year

HOME PERIMETER:        157ft
CEILING:               8ft
GLAZING(DOUBLE VINYL): 250.4sqft
GLAZING(SINGLE):       5.3sqft
FOUNDATION:            raised
SIDING:                lapped 3/4" Redwood heartwood
INTERNAL FINISH:       lath and plaster
INSULATION(wall):      none whatsoever
INSULATION(floor):     double pad W2W carpet over 2" redwood
INSULATION(attic):     6" fiberglass
INTERNAL HEAT LOAD:    1.2kW
INFILTRATION:          moderate to high
ODDITIES:              internal 60,000BTU H2O heater
ODDITIES:              open fireplace
ODDITIES:              dryer in heated space

FUEL(N.Gas) COST:      $1.47/therm    
ELECTRICITY COST:      approx $0.23/kWhr

We have been wearing lots of coats in the winter.  My wife looks like a polar bear.. She wears a polyfill coat over a sweater while washing dishes even.  We start a roaring fire in the fireplace and it makes the living room nice.  But the kids rooms at the back of this rabbit warren are really miserable and the fire exacerbates it with infiltration air.  Insulating the walls would be nice but the inner and outer surfaces preclude it and the bigger losses are thru the windows and infiltration.  House was built in "49".

RE: Depth of water sensing

(OP)
itsmoked - sorry I got confused about your location.  You have an even milder climate than I do in NW Washington (1 mile from ocean).

Both itsmoked and warpspeed, you need to try a tool to zero in on your heat losses and do a what-if. This can show you where you should put your dollars.  Now no heat seems a bit extreme, but you still need to think about where to put the money. Here is one free package http://www.slantfin.com/he2/orderhe2.html you can download (172 MB).  Wirsbo has one I used but you have to beg a bit harder.  There are far more complex models available the can actually analyze walls and sunlight and stuff but they are real complicated and for academics and people really into building engineering.

Generally the ceiling has the higher losses than walls but zero insulation seems bad.  Infiltration can be a real big factor.  Load analysis will not tell you what infiltration rates are.

What follows is my $0.02 (US) on an approach.

Upgrades to the structure return savings each year.  They are more effective dollars. Increasing fuel costs just make them better.

Find someone who can do a blower door test for a reasonable amount.  They may be scarce in your area but you might be able to cobble something together yourself. It is a test where they put a blower in the door (duh) and measure the flow at a given pressure.  Block you chimney.

Double pane glass is not all that bad particularly if it still works. Vinyl is also a pretty effective window material.

There are ways to insulate the walls. Not nifty but doable. With your walls the inside would be the way in.  You can patch plaster better than redwood.  It would be ugly and messey but you could put a hole in each stud bay and bring in someone to spray something into the bays. The something would be foam (expensive but high R value) or cellulose.  The foam would seal better and also provide a vapor barrier.  An alternate would be to put some foam sheets and a vapor barrier on the walls and cover with drywall.   You loose some floor space and  the penetrations (doors and windows) and electrical outlets need to be handled, but if fixes a number of problems.

The fireplace should have an external air supply.   Figure out how to get a duct from the outside to the fireplace. If you have a crawl space this should not be too bad. Be careful - you do not want to creat a situation where the fire can get into the outside air supply unless everything is rated for this. It has to have a damper to close off the outside air when not burning.  Put a damper on top of the chimney. Normal controls (particularly old ones) do not seal the chimney.  It needs to be on the exterior vent where you can actually get a seal.  A sealed glass door helps this whole effort if you can get the air supply inside the doors.  Maybe a heat exchanger you can put in the fireplace and circulate some heated air (maybe back to where the kids are huddled under the blankets). Dryer has the same issues.  Get outside air with a damper to it and close the door to the laundry room if there is one.  Do not vent the dryer to the inside.  Bad water vapor problem and small lint in the air.

I am guessing that "foundation- raised" means a crawl space.  Insulation and a vapor barrier are relatively inexpensive and you can do it yourself if you do not have a thing about spiders (I do).  Air infiltration should be a part of this.  You might consider fiberglass batts between the floor joists and then a vapor barrier.  The fiberglass with an integral  vapor barrier is hard to actually seal.  Unfaced batts and poly seems better. You could also do sheet foam and seal the edges. Foam/tape any penetrations. You may need a plastic film on the ground to keep humidity down in the crawl space.  Every place you have a pipe or wire going through a wall you will lose energy.  The top plate of your walls probably leaks much air into the attic.  Ceiling lights (especially recessed) leak a lot.  Be careful sealing and insulating lights. They may not be rated for insulation contact. One way is to make a box out of something (there is a ceramic based board used to line commercial range exhasusts) to cover them and then seal that box to the ceiling.  Push aside your attic insulation and seal wires, vents, and tops of walls with foam in a can.  Be careful about your insulation.  You should know what it is before you fool around up there if it has been there for amny years. Make sure there is nothing but fiberglass.  Some old granular materials can contain asbestos.

Spray foam on the children. Nah, this makes them too inflexable.

Windows can be improved with another layer of glazing.  Adding storm windows can help but an economic analysis will drive this approach.  A piece of plastic (not a film but an actual sheet of plastic) can be added to the window. This can be internal or external and removable for the summner.  You can use those strips of flexable magnet like on a refrigerator door.  Those window air conditiners are probably big leakers.  Make some insulated drapes for the windows that can be closed at night.  If you or you wife are a bit handy and have a sewing machine that is not hard.  Use some fiber insulating batt inside.  Put the edged is some sort of track to reduce convevtion losses.  Or do the macnetin strip thing.

Upgrade air seals on the doors and windows.  Sliding glass doors are particularly bad performers.

The heating system.  I have to assume there is some sort of heating system in place that does not work.  Can you describe it?  What sort of floor plan do you have.  You mentioned "warren".  If you have an old steam or hot water system it may be usable.

Anyone bidding on a heating system really should do a heat loss analysis before they size the equipment.  Heating contractors frequently just pick someting nice and big that will certainly heat the house.  Then you wind up with something that short cycles because it is way over sized.  Make them show you the numbers.

RE: Depth of water sensing

Great info alternety, I shiver just thinking about ice and snow. Here in Australia, direct solar gain in summer is the problem, not winter heating. It is MUCH easier and cheaper to deal with.

What do you suggest for kitchen ventilation in a very cold climate ? Cooking smells and high humidity require exhausting fairly large volumes of precious warm air. Would a rotary heat exchanger heat recovery system for the kitchen be worth consideration ? Ditto for the laundry and bathroom ?

RE: Depth of water sensing

Thanks to alternety. I will consider these things.

The existing furnace I condemned 5 years ago or so for fear of monoxide was one of those stewpid floor registers that actually sucked in the at the floor on either side of a central wall and exhausted out the wall with a big vane that could direct most heat to one or the other side, all gravity stuff.  It used 17,500BTU of gas.  I suspect it was perhaps 50% efficient.  Truly dreadful, causing massive unpleasant stratification.  Like standing head temperatures of 110F, sitting head temps of 70F, and feet at 45F.   At any-rate, I will be blocking this off and removing what I can. I will re-sheet rock the wall [both sides] and try to match the plaster. I will patch the floor.

I have tentatively selected a new Goodman furnace:
http://www.goodmanmfg.com/consumer/
 GCV90704CXA
 69,000BTU Full input
 64,200BTU Full output
 48,000BTU Half input
 45,000BTU Half output
 21" x 28" x 40"
 135 pounds
 93% AFLU

It is a two stage.  I have done the full energy calc and came up with 51kBTU, which seems about right.  I kinda laugh because finding a 50kBTU is like finding "the corner" while standing in a sphere.  

I believe I will only need the first stage most of the time except for those rare 20F evenings.  This will allow a long even cooking without short cycling.

Twill be mounted in the attic horizontally.  I will run 6 registers.  The return and furnace will be centrally mounted above where the condemned furnace is under the house.

I will saw off the existing flue pipe that comes up the wall that the condemned heater is in under and where it exits the ceiling in the attic.  I will drop a black iron pipe down the old flue pipe from the roof.  It will be braced and mounted under the house and in the attic.  I will run the condensate drain from the new condensing furnace down the same old flue chase.  Then I will foam the top and bottom of the chase.

I'll run a sweeping 90 return from the hallway ceiling return register into the furnace thru an electrostatic filter.  The hot air plenum will of course have the six different register ducts leaving it for all rooms to be heated.

Question: Does anyone know anything about 2 stage heat/cool thermostats or have any recommendations?
 

RE: Depth of water sensing

(OP)
The laundry room should not get particularly humid if you use a washer and dryer.  Give the dryer outside air for input and combustion if it is gas.  Dump the output outside through a vent pipe.  Seal both pipes when not in use.  The home depot grade little flapper dampers are quite useless.

The rotary heat exchanger you are talking about is probably an "energy" recovery unit rather than a "heat" recovery unit.  The energy unit recovers humidity as well as heat.  It also usually will exchange some actual air with the input stream.  If you are trying to get rid of humidity you want the heat recovery one.

I have all the rooms serviced by air that is supplied by a heat recovery unit.  The bathrooms have a switch that lets you turn on/speed up the fan for a preset period.

The kitchen is a special case and a difficult one.  I am very sensitive to cooking emmisions.  One wiff of smoke from frying or something and my sinuses bang shut.  In past houses I have used up to a 1200cfm residential range hood.  Did not fix the problem.  This time I have a commercial hood made by Captive Aire.  1200cfm exhaust and 1200cfm make-up air.  The incomming air enters from a grill on the top front of the hood and more grill that is behind and below the level of the stove.  It basically surrounds the cooking area with an air curtain.  I have built in a water coil in the blower unit that supplies the outside air.  Some people have said I need to heat the air - others say no.  Putting the coil in after installation would be a real horror so I did it when I put it all together.  It uses a pump that senses the coil temperature.  I don't have to turn it in if the wife does not want it running.  It is a significant heat load.

You should not use a heat recovery unit for a range hood.  It will get gummed up.

RE: Depth of water sensing

(OP)
itsmoked.

I just responded and it took my IE instances down and lost the post.  Here I go again.

You mention black pipe.  I am guessing for gas but if not -Black pipe is not a normal flue material.  Check codes before using that.  Plastic is normal for a condensing furnace but you need to see the vendor documentation which is lacking on Goodmans site.  The condensate is corrosive and needs plastic.  It also has to have a trap to keep exhaust gasses out of the house.  Be careful. There is also a flexable stainless gas pipe available.  Again check local codes.  It won't crack in an earthquake like iron will.  That is what I used. It is also easier to run.

Are you thinking about doing this yourself?

I have seen those furnaces for sale on the internet.  An alternative.  Small boiler (they are quite compact and some can be wall hung) in the space where you have the old furnace or you hot water heater.  Use the boiler and an indirect DHW storage tank and you will significantly improve your DHW efficiency.  Run some baseboard tube and fin or buy some attractive old radiators.  You could also do fan and coil units in various places.  Probably more expensive but you could do it with plumbing tools instead of sheet metal knee deep in fiberglass.  Radiant would be quieter.  All that stuff in the attic will lose heat and probably add new air leaks.  When the heater is not running, cold air may descend from the vents.

RE: Depth of water sensing

alternety; Thanks for the comments. I hate when the post chokes... My biggest cause is sometimes I go up the post to copy a posters name.  Something goes wrong and I end up going to that posters specs.. The answer I am working on, of course, vanishes.. AArgh! If my posts get much longer than two sentences I start copying them and pasting them on top of each other in word pad.  Then if something goes wrong I just copy the wordpad back to the post.

Naw black iron pipe is just normal code speak for non-galvanized steel water pipe.  Not supposed to use galvanized in gas service.

Several people have suggested that I run baseboard water heat.  But we are crammed into our little bitty house and finding functional baseboard heat space would be difficult and problematic.  While I constantly think about running cogen; a water cooled, NG fired generator, used as a water heater with "waste" electricity, I think about having to crawl around under the house insulating pipes that actually have a much higher delta to insulate against than the ducts in the attic.

I will use the existing roof jack to vent the new furnace using pvc.


I must mull the attic heat loss problem..

  

RE: Depth of water sensing

Well now I am considering baseboard water heating... I looked at each room and yes they all have resonable places to place "radiators"?

Are they only convection driven on the air side?

What does the piping consist of?
 
How is it insulated?

Is more than one required in a room?

What is the typical water temp?

RE: Depth of water sensing

(OP)
The only packaged co-gen unit I have seen on the market is expensive beyond any reason and I seem to remember they did something I considered dumb (other than pricing).

There are flat panel radiators.

Here is a bit of an out-of-the-box idea.  Radiant heet does not care about gravity.

I will assume that since you have lathe and plaster walls you also have that in the ceiling.  So we won't go for the attic.  This also keeps you out of the fiberglass.  This has merit.

Take PEX (the tubing used for heating by anyone paying attention) and some aluminium sheets designed to hold the tubes.  You can work out your own approach to the spreader plates or buy them ready to use.  Do some furring strips and put this on the ceiling.  Attach drywall to the furring strips. The plates should contact the drywall but it may not be absolutly essential.  Maybe throw on some mud just before applying the drywall and squeeze out the excess while screwing on the drywall.  This needs some experimentation to make sure you can make non-lumpy ceilings.  Dump a bunch more insulation in the attic.  The ceiling is now much hotter (not dangerously so) and attic insulation is a good thing in any event and relatively cheap.  If you could start from scratch I would spray some foam to seal everything. I would put up a vapor barrier before the heating stuff.

Just a thought.

RE: Depth of water sensing

(OP)
We cross posted.  This happens when I spend a day or two finishing a post.

If you use baseboard or stand-alone radiators there is a major convection component.  The slantfin url is oriented to baseboard radiators. That is what they make. These are done by the foot. Radiant floors, walls,ceilings are an area phenomenon.

I have not used it, but play with the Slantfin software and see waht it says. Essentially the house is divided into zones and a thermostat controls each zone. A boiler supplies water to the zones.  It runs when anything calls for heat.  Zone valves (there are other approaches) send hot water to the zone based on the thermostat.  A buffer tank helps with small zones causing short cycling but is not generally required. Many successful system do not use this approach.  Water temp is a function of heat loss and the amount of heat exchanger in the zone.  You want to stay with low temps to insure condensing in the boiler.

If you do DHW the temp will be high in that loop and you may not condense; but it will still better that a regular hot water heater.

I live to confuse with alternatives.

RE: Depth of water sensing

Please anyone:
What is the connection of the heating and the well water
depth monitor ?

<nbucska@pcperipherals DOT com> subj: eng-tips
read FAQ240-1032

RE: Depth of water sensing

Probably none directly, but it is still part of the same project and of interest to some people here.

If the significant drift off topic annoys you, just untick the e-mail notification.

RE: Depth of water sensing

(OP)
There has been a morphing of subject, as explained previously by another poster. As I have also explained, I restarted this thread with a redirection of the topic to get to the people who have set a "notify me" on this thread.  If the site would allow me to edit previous posts I would have noted this in the first post - but it does not.

Is there some relevant reason for your posts and reference to the FAQ?  If you read this post in its entirety you will follow the flow. If you do not; how could you respond to any of it?

RE: Depth of water sensing

Alternety:
The FAQ notice is intended for everyone. 90% of the
FORUM's correspondance is advisors trying to find
out the requirements.

<nbucska@pcperipherals DOT com> subj: eng-tips
read FAQ240-1032

RE: Depth of water sensing

(OP)
We were going to put in the antifreeze today.  Canceled on account of noise.  I have been having real problems with the noise level of the variable speed pump.  I walked around the house and you can hear it in all the rooms on both floors. Now drywall will affect this, but even so. In the hallway outside the boiler room (which is already an enclosed wall) it just reverberates.  The contractor is going to talk to Grundfos.  It is just way too noisy.

I opened up the case on the pump and my guess about what was inside was verified.  It is a simple speed control using what appears to be a triac to run the capacitor start motor. This may be the source for at least some of the noise/vibration particularly at lower speeds.

I don't know where to find another pump if this design is simply intrinsically noisy.

RE: Depth of water sensing

That may be a problem.. A VFD solution is rough too. They make horrendous noise for in a home..  Both audio and EFI.   I know, I run one under the house.

RE: Depth of water sensing

A capacitor start motor must be just about the worst possible type of motor to try to control the speed with. Below full running speed the centrifugal start switch will connect in the start winding and start capacitor. When up to full running speed the start winding is mechanically disconnected. These types of motors are only usually used where massive staring torque is required, certainly not for centrifugal pumps !!

Induction motors also operate from the rotating magnetic field generated by the stator windings. Reducing the voltage without also reducing the frequency is not a very nice way to reduce speed.

Triacs can also have strange characteristics when operating with highly inductive loads. They can spuriously maintain full conduction (not turning off). I am not surprised it is noisy, the induction motor and triac have probably become mortal enemies. I guess what you can hear is the battle raging through the pipework.

The most suitable type of motor for speed control with a triac is the universal ac/dc brush type series motor as used in most power tools and household appliances. If you can change either just the motor, or find a pump with such a motor, it will run smoothly and energy efficiently at any set Rpm right down to almost zero.   

RE: Depth of water sensing

alternety; Are sure you're not hearing air/cavitation noises.

Most of those Grundfos's are pretty darn quiet. I have two buddies running those on their hot water loops with no detectable noise.

RE: Depth of water sensing

It may work quite well at full speed and voltage. My guess is that at reduced voltage the triac is having fits with the inductive load. Triacs sometimes don't always turn off at the zero crossing if current is still flowing.

Try looking at the motor voltage and see if it is rock steady, or jumping around all over the place at low pump speed.

RE: Depth of water sensing

(OP)
I think I mis-spoke about the capacitor.  It is for run  not start.

I have several other smaller Grundfos pumps in the system.  They are indeed very quiet.

The pump and motor are integrated.  Can not replace the motor with something else.

I have found 3 units on the web.  All look like they do exactly the same thing.  They use their regular motor with a triac.  None of them actually provide any data on what they do, but the pictures all have the same sort of motor and there is always the big capacitor if they show and inside picture.

RE: Depth of water sensing

(joke)

NEWS - NASA announces that they've cancelled the entire Manned Space Program so that the engineering and science staff can be reassigned to work on a higher priority project - Alternety's new heating system.



RE: Depth of water sensing

Hey alternety.  I talked to a guy about your circ-pump noise.

He said two things.

One was that most of those circmotors come with multiple speed settings like 5 leads, each one faster and faster.  He said the best way to control the head is to stage the pump.  One zone calling; speed 1, 3 zones; speed 2,  etc.  You may not need the highest setting ever.

The second point is;  noise he has had to service, has ALWAYS been the relief valves WITHOUT EXCEPTION.  They can make horrendous amounts of strange/referred noise.  So make absolutely sure that isn't it.

RE: Depth of water sensing

(OP)
itsmoked - I have some of the multi-winding ones but this is not one of them.  The range of possible flow is pretty large and with potentially small increments.  That is why I chose the variable speed.  It is something to think about if this noise thing turns out to be related to the variable speed. A PLC with more relay outputs maybe. I really wonder if it is simply a defective pump.

The contractor has bled the motor twice.  He says he is sure there is no air.  We purged the system while filling and had the system running for 3 days to purge all the air out with the air extractors.

The pump should not be doing anything funny.  The calculations have the pump matched pretty closely with the full flow of the system.  He pays attention to things like flow rate in pipes and things like that.  There are a lot of little details if you do all the sizing things that are really necessary.  The software does all the hard work so human error is reduced to an almost NASA like level (well NASA management anyway). I played with valves a bit and I really don't notice a significant change in pump noise as I close off loops.  The contractor tried fiddling with the pressure sensor range and got to a point where there was severe hunting and the motor made some really nasty noises - probably near 0 volts.  My PLC may not want to turn things off by going to 0 volts.  I called Omega and the tech support guy recommended the CNi 16D52.  I am looking at it.  The 53 is probably more useful in that it has one analog out and one relay.  I am not sure yet why the D. I have to read more documentation. It may be needed to have a setpoint using their panel input.  It sure looks simpler than writing a program.

I am not sure exactly what your guy means about a relief valve.  He may be thinking about the bypass valve commonly used to accomplish what I am going for with the pressure thing.  Typicaly these systems run the circulator at full sppeed all the time and have a bypass valve on the manifolds to return excess water when there is less than full heat demand in the loops.  This, in effect, controls the pressure across the system like I am trying to do.  But it seemed ugly and not particularly energy efficient.  By feeling pipes and things you can pretty much identify the motor as the source.

RE: Depth of water sensing

No chance of debris in the pump? How much effort is it to strip and check the impeller? The little Grundfos pump in my CH system is pretty quiet and it is fairly easy to strip down. Don't damage the sealing faces! Mine's a three-speed type, so not as sophisticated as yours.

----------------------------------

One day my ship will come in.
But with my luck, I'll be at the airport!

RE: Depth of water sensing

I am not familiar with the particular pump, and grasping at straws here, but does it have to be orientated a certain way ? Motor up, motor down, motor horizontal, etc...

RE: Depth of water sensing

118 when I had a look last time. 163 now. Keep up the good work guys. Who will be 200?

Gunnar Englund
www.gke.org

RE: Depth of water sensing

(OP)
The pumps do have to be in a particular orientation (horizontal I think) and they are.

There should not be anything in the system.  Nothing was soldered.  All the copper is crimped. I will ask the contractor about it though. I have asked him to send me an electronic picture of the system so I can post it here.

RE: Depth of water sensing

Check the pump orientation is actually correct ! The small hot water circulating pumps I have used in solar hot water systems definitely require a vertical motor orientation.

The pumps I have seen, typically use a magnetically coupled rotor and a single ceramic wet bearing. The rotor is supported by the attraction of the rotating magnetic field as well as the bearing. If the shaft is horizontal, the rotor can "fall" slightly crooked when the pump is turned off. When powered up again. the rotor can then sometimes wobble or become unstable somehow, (not always) and create a fluttering noise.


RE: Depth of water sensing

(OP)
We are getting a replacement pump in to see if that fixes it.  We will also take apart the current one and see if there is something in the pump.  It is starting to get chilly and there is no antifreze in yet.

itsmoked - have you decided what you are going to do for your heating system?

I am having a real problem comming up with an affordable PLC solution to my control problem.

RE: Depth of water sensing

Affordable PLC?  Check out the TWIDO.

http://www.modicon.com/PLCIO/twido/

Look on the right side for the starter packs.

These are very powerful and cheap.  I think they are even wireless programmable. Very small footprint.


My furnace?

I went all over the place on this choice.  Man!  I did extensive research on the hydronic wall jobs.  But didn't want the headache of insulating more than a dozen lines staring from a manifold.

So then I looked into an air handler with a water heated coil.  This had a ton of great advantages.  But after crawling around under the house for a day estimating piping for it, it became clear I would need to do over 140 solder connections while laying on my back in limited space in the dark.  I nixed that too <sniff>.

I ordered a multistage gas furnace with a variable speed blower with 93% efficiency.

Spent the last two days routing gas and electricity to where it will reside in the attic.

RE: Depth of water sensing

(OP)
Thanks, I will look at them.  I actually have their site up on another screen at the moment.

PEX would allow a continuous run without joints. And it is flexible.  You need a tool but you could probably get a plumber or heating person to make the joints.

Appears too late for this, but just FYI.  If you need to rearrange water pipes or anything keep this stuff in mind.

RE: Depth of water sensing

Great thread, classic.  Alternety, another way u can control ur flow rate is by running the motor output through an infinitely variable transmission.  That way the motor only cares about on/off and runs at constant speed. Controlling the IVT lets u vary the pump rpms and thus flow rate.

chris

RE: Depth of water sensing

Reads like a novel sorta don't it?

RE: Depth of water sensing

Right out of an episode of "Lonesome Dove".

RE: Depth of water sensing

Just as well the language hasn't decended to "Deadwood" as yet...

RE: Depth of water sensing

We're not quite at 200 posts yet... ...anyone know any good jokes?

PS: It's been near freezing +0.7C (33F) the past few nights (NS, Canada). If this keeps up, I might eventually have to turn on my simple cheap electric heaters.

RE: Depth of water sensing

VE1BLL you are so cruel...

I pay 26 cents US a kWhr...

1500W heater X 8hrs = 12kWhr

12kWhr X 0.26 = $3.12

$3.12 X 30Days = $93.60/Month

and that's just one room.

People wonder why we pay $300 for a cord of Oak.

RE: Depth of water sensing

26 'Mericun cents per kWh... geesh. Here in NS, Canada it is around ten Canadian centettes per kWh. With taxes it might round up to something close to US$.10 per kWh.  In central Canada (Hydro, nookes) it is as low as around Cdn$0.05 per kWh.

My total heating bill has always been just under Cdn$1k per year (based on integrating under the winter hump). With the latest rate hikes, it might go just over Cdn$1. We keep the house warm at 21C and 18C at night. 2800 sg ft plus basement.

The key is to invest the capital into passive solar (22 sq m of glass facing South, fully shaded in summer by the way) and very good insulation (walls R30, roof R40, outside basement R10). These features tend to be reliable, don't need electrical power to run, and are very, very, very quiet.

I've seen my share of heat pump systems where the electrical power consumption for all the pumps and controllers was higher than my baseboard heaters.

It's nice to have hobbies, but not a heating system...

How's the post count now, 175?

 

RE: Depth of water sensing

Why not just move to a land of palm trees blue skies and balmy tropical breezes ?

RE: Depth of water sensing

V1BLL

Please send:
EXTENSION CORD, LONG, 8AWG, PLUGGED IN

Warp... That usually comes with too hot, hot, hot that, last I looked, costs even more to remedy than cold cold cold.

RE: Depth of water sensing

No no no, that's not nearly engineerish enough.  Even cave men had extension cords. V1BLL please build a large tesla coil designed to direct flux primarily into the southern Ohio region.  I will correspondingly build several receiving coils to receive said 5 cent power.

RE: Depth of water sensing

NO! NO! Don't listen to him!! Point it at Northern Calif!!

RE: Depth of water sensing

Heck at 5c a kWhr u should build a coil to power the WHOLE WORLD, just like Tesla wanted to do.

This inspires me as to another way to find the well water level.  Float a coil on the water level and fire up a huge tesla coil on the surface.  From the induced current in the well coil u can calculate how far apart the two coils are.

RE: Depth of water sensing

"Why not just move to a land of palm trees, blue skies and balmy tropical breezes?"

That's in my long term plans since my wife is from a nice quiet, peaceful island in the Philippines.

Getting back on topic, I think it's important to keep the total capital cost of your heating system in-line with the possible savings. In other words, spending tens of thousands of dollars, to save several hundreds, provides a pay back period of several infinities.

Even with my rather modest investment in energy efficiencies and passive solar, I've already reached a point where it barely makes sense to worry about my heating bill any further. My car's gasoline bill is about twice my home heating bill.

RE: Depth of water sensing

Hi!  Am a little hesitant to post much, being a complete neophyte to eng-tips, but might have a useful idea ...

alternety: An interesting problem you have, with the need for a water depth sensor I mean.  Very similar to one I'm having with my well.  It's a shallow one, by comparison (only 265 ft).

This thread is the reason I found (and joined) eng-tips.com, while looking for a solution for my own well, for which I need to monitor water depth.  Long story -- details if they seem pertinent ...

Now before I drag this thread back to the original question, I thought I should ask if you ever got the well depth sensor problem resolved.  I haven't read every word posted to this thread, but it kind of appears you still don't have a way to monitor the depth, right?  I just thought that before I go into my idea of how to solve it, I thought I'd better be sure it's still a problem (and potentially save a lot of useless typing).  I think the sensor idea I came up with would be extendible to that depth, althought some purists might consider it a bit of a kludge.  OTOH, the price is right -- really cheap.

Question is, is it stll a problem that needs solving?

RE: Depth of water sensing

(OP)
Welcome to the thread that won't die 14.

I have been seriously crunched on just trying to get the house livable.  My probable approach will be to use a power curve I obtained from the pump vendor and only measure while the pump is running.

Based on my success (not!) with getting a well-empty probe down the hole I suspect I should just forget about trying to put anything down there unless I have to pull the pump for some reason (way down on my list of things I would like to have to do).  I could of course try a rocket boosted sensor and just blow through whatever got in the way.

I would be interested in your ideas even if I can't implement.  I strongly suspect that several others monitoring this thread would also be interested.  This place is about ideas.  It is an odd form of recreation favored by engineers while others look on and think we should get out more.

RE: Depth of water sensing

Lots of people are interested in sensing the depth of well water. Post away if you have time.


PS: Is the '200 Winner' going to be the 200th post (199th reply), or the 200th reply ?

RE: Depth of water sensing

Most definitely interested here too.

RE: Depth of water sensing

I just had another idea.  Set up a small radar unit and aim it down the hole.  It should ignore all the junk in the way and give u a good relection off the water surface.


RE: Depth of water sensing

How about a six hundred foot long dipstick ?

RE: Depth of water sensing

"...six hundred foot long dipstick..."

Just make a print-out of this 600-foot-long thread onto fan-fold paper and lower it into the well. Then pull it out and find the damp section.


PS: Radar was already mentioned on '27 Jul 05 13:55'. However, well-depth measurement techniques involving use of the solar neutrino flux are all still up for grabs.

RE: Depth of water sensing

(OP)
Status

Yesterday I told the contractor to put a fixed speed pump in and a pressure bypass across the manifold.

We replaced the variable speed pump with a new one (same kind) and nothing changed with the noise.  If anything the replacement was a bit noiser.

The distributer for the pump came out and agreed that the noise was too high for residential use.  Now the question is whether Grundfoss will take back the pumps.  They are almost $1000 each.

I did  a little bit of playing around with the pump. I got a newer manual online and found that the speed could be adjusted manually.  Even at what should be full speed it makes much noise.  This feels wrong if it is the TRIAC causing the problem.  At full speed the TRIAC should not be doing anything part way to the cycle.

I would like to find a DC driven replacement with the theory that after I am moved in an get boared I could try PRM on a DC motor with better results.  A good PM motor should aldo be more efficient in normal operations.

The pump is designed for about 12.5 GPM at 11 ft of head, 1 1/4" flanges.  Anyone know of one.  I am looking into one from March.

RE: Depth of water sensing

I saw some 8 HP Briggs & Stratton motors on eBay that ran on 12 - 48 volts.  They were really small for the power, measuring only about 6" diameter.  I was thinking about buying some to build an electric car but I haven't won the lottery yet.  They cost $399.


RE: Depth of water sensing

Now, someone must be responsible for this. What if said responsible made a summary to keep us less informed guys updated with regard to what this thread is about nowadays? It would also be very nice to know what you have found so far. If possible, make a list of recommended techniques for Depth of Water Sensing - maybe there should be an FAQ on it?

We need this summary before the 200 postings milestone  and someone (alternety, wagnerc, smoked, VE1BLL for instance) should feel guilty enough to do it.

Gunnar Englund
www.gke.org

RE: Depth of water sensing

Hey man, don't try to blame me!

RE: Depth of water sensing

Summary:
1) There's a hundred ways to measure the depth of water in a well, but none are perfect.
2) Complicate heating systems are, ah, er, complicated. It's nice to have hobbies.
3) A $30k heating system is a very bad start on trying to save money.
4) Pumps are noisy. Quiet pumps installed perfectly are still noisy.

How's the count?

RE: Depth of water sensing

(OP)
OK very short summary from off the top of my head.

Two best ways to sense water depth:
1 - bubbling tube down the well and monitor pressure at top.  Needs air pump to do the bubbling. Air needs to be clean and oil free.

2 - measure pump power draw against manufacturers curve or calibrate the pump yourself if you think you can get something down the hole to find the water level.

A variable speed circulating pump can be used in a hydronic heating system main loop if pressure across the manifolds is the controlling element. It replaces the more common residential approach of running the pump at full speed (even when a very small amount of water is being called for in the operating zone) and bypass excess water from the source to return manifolds using a mechanical pressure relief valve.

A variable speed motor and a pressure sensor are not enough to form a control loop with a setpoint.  You have to have a PLC or some such thing to control the system.  There are very many PLCs available.  You need one with analog in and out with one digital in that can be used to turn the pump on and off when there is heat demend.

The variable speed pump must be quiet. The Grundfoss variable speed pump is too noisy to live with.

I need, I believe, a quiet PM DC motor/pump in the 200 W range  and a suitable centrifigual pump to replace the Grundfoss (12.2 GPM @ 10.8 ft of head). If there is a suitable controller with it or I can find a PLC that seems to work (I have looked at a bunch without identifying one) I would stay variable speed.  If not, I need the same motor so I can go to variable speed later when I have moved in and have some time.

itsmoked is going for forced air heating.

That is, I think, the high points in the thread.

RE: Depth of water sensing

That is all very well (no pun) and interesting. But the one thing that I remember from this thread is "the sacrifice of a small mammal behind the well head at midnight". It hasn't been mentioned in the otherwise excellent summaries above.

Didn't it work out? And where is Smoked? I am eagerly awaiting his summary. Something tells me that he has a slightly different view than those presented.

Gunnar Englund
www.gke.org

RE: Depth of water sensing

Only 200 watts?  I thought u needed a lot more power than that to drive the heating system.  There are 300 W DC motors on eBay going in the $25 range.  They're Krollman electric scooter motors.



RE: Depth of water sensing

(OP)
Multiple small to medium mammals have not helped.  What size range would a contractor be?

RE: Depth of water sensing

Are HVAC contractors mammals?


Count status:
This is Reply #198, thus Posting #199.
Next after this will be Posting #200.
Next after that will be Reply #200.

RE: Depth of water sensing

Contractors are usually large mammals.  Don't think they will fall down to the bottom of the well, yet they might give you some vocal feedback about the installation while they fall.

What about a 2-speed motor?

RE: Depth of water sensing

Smoked!? Where are you?

Gunnar Englund
www.gke.org

RE: Depth of water sensing

felixc is Posting #200.
skogsgurra is Reply #200.
Congratulations.
Next milestone is 250.

Snakes are reptilian, not mammalian. Check for nipples.

RE: Depth of water sensing

.
Where am I?

In the  A T T I C!!

Putting in my furnace...
Trying to not have any of my three friends, wife or kids that are helping, put any of their feet thru the plaster.

Trying to put a 4 x 8 ft sheet of 3/4" plywood thru a 3-8" access followed by a 140lb furnace.  Running gas lines, drain lines, electricity and vent pipes.

Pouring thru the furnace manual that is 40 pages of solid 8-point type.  Sorting out updrafts, downdrafts, counter
flow, alternate left and right horizontal mounting....

All day tomorrow too.

As much trouble as alternety is having.. I am glad I went with forced air.


This thread? In a nut-shell, {as taken from a small animal}....

A guy wants to measure his deepwell water depth to; 1) prevent the pump from running dry; 2) control the pump to maximize production.

Instead of buying a purpose built down hole pressure transducer (not cheap but the definitive solution), which is a drop in the bucket against the rest of the $70k installation and then strapping it to the pipe and installing it with the pump, he instead:

Puts the pump wayyyyyyyyy down a well and THEN asks us for
"cheap" well depth monitor.

Many problematic and Rube Goldbird suggestions are brought forth.  Ultimately one is attempted that results in a stuck/trapped/tangled rat's-nest-of-sorrow halfway down.

To allow psychological aquifer recharge: Problem and solution temporarily abandoned.

Because the victi...er individual lives north of the 35 latitude he notices while sacrificing small animals that their fur is getting thick and luxurious.  His thoughts turn to preventing death thru exposure, frost bite and the inevitable gangrene that follows.

He turns his focus to his insanely complex heating system. A virtual tinkerers Nirvana! Sadly, it evolves into his  personal, family-sized, Chernobyl!

His thousand dollar "nearly silent" Grundfos circulation pump sounds like 15kAmps surging thru electrodes into a 100 tons of bauxite!

His crack installer followed all the rules installing the pump.
Sadly it made no difference.

The "air was bled from the system".
Sadly it made no difference.

A new pump was wrestled into place.
Sadly it made no difference.

More animals died.
Sadly it made no difference.

Now he is looking for a different brand pump.
Sadly IT will make no difference.

RE: Depth of water sensing

Thanks Smoked. I think that I got the whole picture now. You saved me a lot of reading up and also - I understand now - some painful reading experiences.

Gunnar Englund
www.gke.org

RE: Depth of water sensing

(OP)
Acutally itsmoked, it really is not that complicated. And I have detected almost no radiation leakage outside my property. It is a high end system but that is mostly a function of a large number of zones and the controls for the system. The system controls are normal Tekmar devices built for this sort of thing. The only thing really different is the variable speed pump instead of constant speed with a pressure bypass.  The variable sped pump is used in commercial work to keep energy costs down.  We figure that the Grundfoss people don't think the pump is noisy because it is mostly used in commercial installations where no one cares if it is noisy in a room full of big stuff. Hence they have had "no warranty returns" on the pump.

Noise wise (not having aluminum refining experience) I was thinking more along the lines of those machines that chew up trees.

Good luck on your installation.  It sounds like a lot of fun. I spent yesterday gluing cap stones along one side of the foundation.  I got tired of working inside, the weather was good so I did that to help out the guys putting up stone.

I have a couple of pictures of the reactor room but I don't think this board allows posting them.

RE: Depth of water sensing

Sound deadening systems for pipes?  Pump grumble or cavitation noise?  There are systems to reduce noise in pipe systems, but more the kind of noise generated by faucets and valves.  I know about this one:   www. cali.ca  but they don't have an english page.  If you email them in english they will answer for sure.

Felixc

RE: Depth of water sensing

Have you tried consulting an exorcist ?

RE: Depth of water sensing

I'm embarrassed to note that it was two week ago when I asked if the well depth measurenmt problem was solved, and y'all answered right away that you'd be interested in what I was doing to solve a similar problem.  Shucks -- got real busy here for awhile I guess ...

My solution is for a well that's not so deep (265 ft), and I haven't done it yet, but am about to make a first attempt at it, and will hopefully have it in sometime next week, if all goes well#### as planned.

I'm figuring on using a Freescale pressure sensor (MPXH6400A), which will measure up to 58 psi absolute.  If I subtract about 11 psi atmospheric pressure (at 7200 ft), I get a useful range of measurement of 47 psi, or about 108 feet.  My static depth has never been better than about 160 feet, and the pump is located at about 190 ft, with 70 un-used feet of hole below that (which I'd like to use).  So if I put the sensor at or just below the pump, I'll be able to measure the entire range with this one sensor.  One reason to choose this sensor, rather than a higher pressure one that I could put at the bottom, is that it comes in the really tiny package that I can fit inside a 1/2" copper pipe to use as a housing.

The reason my pump isn't nearer the bottom is because there's something wrong with the casing near the 190 ft level.  I don't know if it's collapsed, offset, damaged, or what.  The well was drilled in 1971, and I'm the second owner, with no way to find out what happened.  Somewhat shoddy, low-bid job, I suspect.  Anyhow, my goal with the sensors is to maximize production of the current well such that I don't have to dump 6 or 8 grand into drilling another hole.  I may eventually need to, but by then, city water will likely be available.   (It's getting close all the time.  We used to be 15 miles out of town, and now it's only about 1/2 mile away.)  We only now have occasional trouble since we've just put in a bit of lawn in the back, and have expanded the garden.  We really only have trouble when the wife wants to do three loads of laundry on a Saturday morning, just after the lawn and garden have been watered (all on timers), and guests have arrived for the week.  I guess it's an old enough well that you can't expect recovery to be great anymore.  Maybe I need to investigate getting it flushed or washed out somehow to improve it.  But I also know the water table is dropping a bit here, and this being a fairly shallow well anyhow, I might have to bite the bullet and replace it.  When it does go almost dry, the extra turbulence busts loose a lot of sand and cloudy kind of crap, but it clears quickly if we let it alone for awhile.  I've put a sediment filter on it -- which appears to be nothing compared to the level of filtering you've had to do.

So, you might ask, what does any of this have to do with your well?  Nothing maybe, in that I seen you've already considered the sensors from Freescale.  But I do have this to add -- I note that the absolute maximum pressure for these sensors is four times the rated pressure.  If you look over what they tell you about the parts, you find that the output saturates or hits the supply rail, and of course won't put out anymore than full scale.  That's understandable, but then why is the maximum pressure four times the max operating pressure?  I asked them, via email, what happens when you exceed this pressure, and then bring it back to within range.  They replied that the burst pressure is two to three times the max allowed pressure, so they've really left themselves a lot of margin, even at 4x operating prssure.  Basically, it would start to work again when the pressure drops to within range, but there was some fine-print disclaimer wording that implied they won't guarantee that it will work if you run it too high.  (I guess I should go look it up so I know *exactly* what it says.)  I suppose they don't want to guarantee it, because then you could hold them to it, but as long as it doesn't bust the die or blow the case apart, I'd bet it would work great.  One could test this on the surface easily enough -- hook the 150 psi sensor to a small tank and blow it up to 300 psi, and come back in a week and test it in normal range to see if it survived.  The idea then, is to use two of these, one set where the pressure would be almost full scale at your highest expected static depth, and one below that.  BTW, if you suspect the water coming in is somewhere near the 400 ft depth point, you could be cautious and make it easy on the sensor by setting it just below this point.  That way, you can pump only a measured length of time beyond the point where the lower sensor goes dry, and know that you weren't going to run the pump dry.  So anyhow, you'd have two sensors, one of which would be giving you good data.  If you could locate them close enough together, they'd both put out valid values when the depth was right, thereby validating the other's reading.

The price is even right for these sensors, in that Freescale seems happy to send out samples of these.  One minor problem, however, is that they're only good for measuring dry air.  The solution is to use a short head tube filled with silicone oil, with trapped air above the oil.  This stuff is pretty harmless, so you don't need to fret having a few drops in your well.  Several ways to be sure it doesn't escape.  I've got a sample of this stuff, which I'd be willing to share with anyone doing similar tinkering.  My sample is pretty thin (50 centistokes viscosity), but with a fairly fine capillary tube it should work fine.

That's the idea, anyhow -- hope it helps.  With my casing problem, eventually, I hope to get a very thin submsersible camera to chuck down my well to have a look around at what the trouble is at the 190 ft level.  Then I'll have to figure out if I can get past it with a slim-line pump, wheter some kind of repair might be possible, or if I have to just re-drill the thing.  I'd sure like to have more capacity at times.  Anyone here know of a submersible camera as small as 1/2" diameter, including light source?  Color preferred, of course.  I might be able to use something a bit bigger, but I've got 5" casing and a pump that's just under 4", so am not sure I can count on slipping much more than 1/2" past the pump, particularly where the problem is.  That reminds me: I meant to mention that I'm planning to use a long length of poly-pipe to send this thing down the well, so that there's little chance it could get hooked on something.  I know I can get 1/2" poly in 250 ft rolls.  Not sure how I'd join two of them to go 500 feet, however.  Tricky at best.  Looks like maybe you could use a camera too, for finding out what got stuck down there a hundred feet (or did you get that extracted already?).

Sorry this got verbose -- hope it doesn't choke when I try to submit it.  I really didn't intend to double the length of this thread in one swell foop ...

S^2

RE: Depth of water sensing

14erclimber; very interesting.

Generally when you over pressure pressure transducers they experience a shift.  Not good.  Usually you have a full scale pressure.  And a burst pressure.  If you dally in the range between these two you run the LIKEY result of an offset shift.  Hence your depth measurement may jump a few feet.  Might this confuse the heck out of you?

Could you improve your capacity by adding another tank so your pump can run longer?  Or does it just run dry?  Sounds like the latter.

Can you get a driller to just run a drill down your existing hole to nock out the kink?  Or could you make a sturdy 2x8 gantry and using a cheap car winch rapidly yank your pump.  Then lower a very heavy slender weight on a piece of steel cable then run it past the kink.  Next run it up and down to essentially saw the kink out?

Sounds like fun to me! :)

RE: Depth of water sensing

Absolutely fascinating.
I learned from both the serious and the humorous.

Here is an extrapolation that may help.  

Your real goal is to have more time hinting wild geese.

Then if you can catch more flies with honey, then maybe you can catch more geese with bottled water????

RE: Depth of water sensing

(OP)
For those of you tracking this thread - FYI I just posted on the HVAC group to ask about the pumping.  I am just getting nowhere and Grundfos has been very slow in responding to the noise problem.  I got to get this fixed.

RE: Depth of water sensing

I finally finished installing my furnace.  Yes!
Took about a 120HRs!!  Gads.
The two stage heat is fantastic!





RE: Depth of water sensing

HRs?  Hairy Restarts?  Hopeful Run-ups?  
I'd post pichurs too, if'n it took me that long.
Just KIDDING.  Good job.
<als>

RE: Depth of water sensing

(OP)
Really looks nice.  Wish I had one.

RE: Depth of water sensing

Wow, that's an accomplishment.  Just the kind of "damn the torpedoes" type on install I might try.  Like how I'll spend 30 minutes writing a script so I won't have to type a 10 second command line.

RE: Depth of water sensing

Hahahah. A loser... Just like the rest of us!

Just spent two man-weeks of spare time studying which of two $400 printers to buy. (decided to postpone a purchase!!)
Sheesh.

Sorry to hear you're still having problems alternety.  Have you tried running the pump short looped into a pail to see if it is noisy Then?

I still think it's the installation.. Not the pump.

RE: Depth of water sensing

(OP)
No we have not tried a pail.  For a short time we had a newer version of the pump where we could control the speed manually but before I played with it Grundfos took it back.

I am looking at a Taco 0012 pump as a possible replacement.  It has a much shallower pump curve.  Pressure does not shoot up at low flow.  Ought to be easier to control.

I am going to see how much current the 0-10V input on the pump draws and see if I can make an external control from a battery and a pot.  I just replaced the fuse in my meter (again) after trying to use it as a welder (again) in conjunction with my well pump DC supply.

I am spending most every day working on interior things to get to drywall/insulation.  It is getting cold and it is really unpleasent working out there.  I get cold easilly.

RE: Depth of water sensing

I was just going to recommend Taco.  My buddy's Grunfos hot water circulator pump just choked and he was shocked at the replacement price so we looked around and found Taco.  It was a third less money and quieter.

And yes I'm sure having walls will help with heating.

RE: Depth of water sensing

"...having walls will help with heating."

WALLS: without question.
WELLS: rather dubious...

RE: Depth of water sensing

(OP)
The contractor is big on Grundfos.  He has used them for years and says he had reliability problems with Taco.  But the curves look better and if what I read on their site is correct, the whole line is available in variable speed.

I have walls - they are just thin and full of holes (roof vents and temp doors.  A couple of months ago while getting ready to install an exterior door I noticed the threshold was not what I had ordered.  Two months go by.  The vendor finally tells the lumber yard that they have not made those for a couple of years and don't have any.  It appears no one wanted actual insulation in the them except in Montana.  The ones discontiuued also actually appeared to keep water out of the wall.  Not wanted either.  Yet another oddity.  The knob set pocket (where the latch goes into when the door is closed) has reinforcing metal to resist forced entry. The pocket for the deadbolt does not.  Duuh.

I am not getting much activity on the HVAC post.  I sure hope I get some good feedback from someone who does this.

RE: Depth of water sensing

The mother of all threads...

Winter is coming to the northern hemisphere. I hope you all are doing well (find pun). At least those of you that don't thrive on hot air. Sometimes so hot that it smokes (find pun).

Gunnar Englund
www.gke.org

RE: Depth of water sensing

sheesh...

I won't mention that the control transformer on my new furnace just through a lamination... It started buzzing soooo loudly that I just turned the furnace off...

40VA.... 70dBA screwed to large sheet-metal panel.

What is it with noisy heating systems?!?!?!?!

RE: Depth of water sensing

Sometimes my baseboard electric heaters are very noisy ('tick tick tick' due to thermal expansion and contraction). The fix is to wander over and give them a swift kick - that usually shuts them up for the season. Once in a while, if things are really really quiet , you can hear the relays in the basement click over.

RE: Depth of water sensing

There is nothing better than radiant heat.  No dust blowing gas forced air, no artificial drying of the air and it is much quieter.  Although with warm water baseboards, the thermal change might be slower, but that jus makes the creaking and ticking last longer!

Now, where are the engineer that are going to make a quiet radiant heat system that is cost competitive enough to become the standard in even low cost housing?

RE: Depth of water sensing

(OP)
A simple system should not be too bad price wise.  But comnponents are expensive.  If you do a slab on grade with radiant and do just one or two zones it is pretty straight forward.  A home owner can lay the PEX (heat piping) to save some cost.  Against a low end "scorched air" system it is probaly nor cheaper but if you go for a high efficiency air furnace it maght work out better.

It should be very quiet.  My boiler, a Weil-Mclean ultra, is so quiet you sort of have to look at the displays to see if it is heating.  Other small constant speed pumps are also very quiet.

Use an indirect water heating from the boiler and it saves the cost of a hot water heater (and periodic replacement), gives more of a hot water supply and runs at appreciably higher efficiency than standalone water heaters. The boilers are direct vent so no chimeny; just some PVC pipe, No interior combustion air is used in sealed systems.  They use a parallel or concentric PVC pipe.

If done correctly there should be no expansion/contraction noises in the systems feeding the floor.

There are many possible variants.

RE: Depth of water sensing

alternety;  Have you considered using a pump per loop?
Don't laugh.  You could probably use the absolute smallest least expensive pump found, a tiny Taco or whatever.  All your noise problems would probably vanish.  Certainly your pressure/flow control expense, complexity and hassle would be avoided.  You could possibly use, on certain loops, one pump for two loops. Etc.  Your control would come down to heat called for? => turn on the pump.  You could even rid yourself of solenoid valves.

Ah yes another brilliant suggestion!

RE: Depth of water sensing

(OP)
That would be pretty hard to implement.  There are 6 sub-manifolds buried in walls.  Each one of these has a bunch of loops.  Some zones have more than one loop.  I would still have the same problems with pressure accross sub-manifolds.

The other thing is that this pump actually circulates the hot water from the buffer tank to make it available to the sub manifolds at a fairly even temperature.  This is a secondary loop. I am not completely sure even 6 pumps would work correctly with the existing piping.

I am still trying to get info on the system approach.  The Taco 0012 has a much flatter curve and seems to me to be a better approach to variable speed because it feels like less pressure varaition is necessary for control.  A couple of people have said that the Tacos are quieter. You were one who mentioned them.  My contractor says he stopped using them because they were too noisy.  I asked him to see if he can find and installation where I could actually hear a 0012.

Still doing wiring (low voltage).  Talk about more time than I ever eexpected.

RE: Depth of water sensing

Man... this sounds like a grand scheme that has really gotten out of hand.

Well.... let me know after you're done playing..

I know how to install forced air systems now..

And VE1BLL can help with baseboards.

RE: Depth of water sensing

Alt if u can live a few more years u should apply for the job of Starship Engineer.

RE: Depth of water sensing

Now you are talking. A thermal hybrid booster hooked up to the warp drive engine.

RE: Depth of water sensing

Heck, just shoot a rock with a Phasor.

RE: Depth of water sensing

Have you got a handle on how a simple bubbler system would work?

RE: Depth of water sensing

Groan.... You obviously haven't read this entire thread like a good boy... Have you?hammer

RE: Depth of water sensing

Life is so short.

RE: Depth of water sensing

(OP)
As noted - it is up there.  Someday I might try to get a tube down the hole.  Until then, measuring pump current is reasonably accurate.

For those of you following the saga - the heating system is "fixed"!!

Fix sucks, but it is a fix.  Variable speed pump was removed and replaced with a fixed speed pump from the same manufacturer.  The noise seemes to be associated with the speed control but not particularly with the actual speed setting.  This makes no sense to me.  A full-on TRIAC should not mess with the motor noise characteristics. We sent a pump back and the factory listened, the distributer came and listened, a factory rep came up from Seattle and listened, everyone said yeah, thats normal.  But, as requested, the rep brought a fixed speed pump.  We first swapped a newer generation controller on the installed pump.  Noise level seemed to change but actually worse.  New pump is the next smaller unit.  Quite expensive pressure sensing system is providing esthetic interest to the wall with the numbers on the backlit LCD.

A bypass valve was added to work with the pump.  Looks a bit funky because there was no space left on the wall.

System is now near silent; as it should be.

That was two weeks ago. We finally got the antifreeze in the system on Thursday so I can stop circulating water through the inside and outside loops to try to keep things from freezing. No heat, just moving the water among the masses. We had to get the system fixed and purged of air before the antifreeze. I also can now stop watching the weather so avidly to see just how cold they expect it to get at night.  It has been in the upper 20's a few times.

Other things progress slowly. We had to replace the installed outside doors and replace the jambs for several more (bad measurements by one of the builders).  Taking the first door apart showed the previous high priced talent did a half-assed caulking job.  I seem to have been unable to explain to most of them that it is either caulked or not caulked - there is no mostly caulked or caulked enough to get the bastard owner off our butts. The also did not actually fasten the door into the house with anyhthing but a few finishing nails in the brick mould (which is itself only lightly attached to the door).  I had to have steel plates made to make any reasonable attachment of the deadbolt to the building.  It seems to be a "standard" construction among doors that the latch points have very little ability to actually hit any strong part of the door framing.  As delivered, two screws just get inside the edge of the 2X and two get in about 3/4" back from the edge of the 2X.  Not too hard to break down.

I went to install an exhasut fan and discovered they had installed the 3" thick wooden mounting plate they made, upside down and backwards.  The fan is non-symetric and I had to pry out the wood which was already mortered into the stone wall.  Stone will have to be removed and repaired to allow the properly oriented wood to be installed. Power wires need to be relocated and there is esentially no access space inside the wall. While playing with this I discovered that, unlike what I told him to do and what the guy said he had done, there was not a drop of sealant anywhere in the assembly. Nowhere. Direct paths from the drain plane and stone into the sheathing and interior wall.  He installed other mounting plates in the stone wall.

I also believe I am over achieving on the amount of low voltage wire installed.

Don't say it.

RE: Depth of water sensing

I won't... lol

Glad you got your silence at last.

Sorry about the construction short falls. Sounds like you have to personally inspect stuff before it is covered up and include that in the contract in LARGE letters.

RE: Depth of water sensing

"...construction short falls..."

If you accidently stumble across a couple of needles without really trying, then you can rest assured that the haystack probably contains many more needles.


Data point:

We had a storm and electric power failure over the weekend. The power went out at about 3am early Saturday morning. The outside temperature was below freezing all day on Saturday. By bedtime on Saturday night, still no power and no source of heat (house is all electric), the house temperature was down to...

...+19C (about66F).

Passive solar, good insulation.

RE: Depth of water sensing

Indeed! Though I can't imagine why You don't have an awesome back up generator.

When I had an aircraft carrier deck mounted generator I'd throw extension cords over all my neighbor's fences so they could run a few lights and their refrigerators.  They liked that!

RE: Depth of water sensing

(OP)
Where on earth did you find the room to park an aircraft carrier?

RE: Depth of water sensing

Naw didn't STILL have it attached.  However I'm sure that the Carrier it was removed from came up a foot on its water line when they removed it.  It was a 5kW generator that (get this) was 36 inches in diameter and 30 inches long.  The outer generator housing was steel 1-7/8 inch thick.  It was powered by a water-cooled in-line industrial 4 with a gravity cooling system.  All mounted on a 2-1/4 inch thick solid Cast Iron skid that was 6 feet by 3 feet.

I know what they went thru building the Pyramids.

RE: Depth of water sensing

Now that's what I'm talkin about!  I bet that gen just laughed at hail storms.  Sucker was designed to take high speed shrapnel and blast.

Alt, u know what they say, if u want something done right...


RE: Depth of water sensing

(OP)
I want one of those.  It can double as a seismic anchor and pillbox.  And I need a generator.

RE: Depth of water sensing

It had over heating problems and everytime the Power failed I had to dissasemble the carburetor that had gunked totally.  Further more it needed 36V to start as it some how motored the generator to start the engine.  And it needed a load applied to it or it wouldn't try to start.

I could get no manual for it...

I taught my son how to use a cutting torch on it...

RE: Depth of water sensing

  No,not the cutting torch...   Such a sad way to go.   You could have at least shorted out the outputs and run it till the flames got too high.{;->

RE: Depth of water sensing

DOH!!

I must be getting old.   I only ever retired my internal combustion engines by the tried and true; excessive RPM with no oil method... Dang.


I always wondered how many kw it really was...  I should have run tests..  If it actually put out 10kW...  Cripes it was the frame size of a 100kW, I might have preserved it.
 
After several, work-away-in-the-rain-with-a-flashlight to get it running only-to-have-the-power-come-back-on cycles my patience was null and void.

RE: Depth of water sensing

Guess I need to add a bit of input to the N.E.T.(*) about
now;  you finally got to something important. <g>

I once had a 400 cycle(!) 3-phase military surplus (probably
Air Force?) that pretty much fits that same description.
Came with its own axle.  The windings and brushes were very
similar to what I am seeing right now on a 400 HP D.C. motor.
Wound rotor, IIRC.  37.5 hp horizontal 4-cylinder.
With an added exciter about the same size as a 10 HP.
1400 watts. Forever.  Same carburator problems, with the
added bonus of a flakey fuel pump (with its own little
manual handle).  Sure do miss it.  NOT.

<als>
(*) Never Ending Thread


RE: Depth of water sensing

I went to a military demonstration day in Seattle once.  They had a full military field hospital set up and were, of course, running it with a generator.  It was in a box about the size of classic military foot locker only twice as tall. The generator only occupied the bottom half. The doors were open.  The prime-mover was a gas turbine.  A little black hose about the diameter of your little finger snaked over to a tanker truck about 100 feet away.  The turbine was probably 20" in diameter and 24" long and it was hooked to a generator that was probably 16" in diameter and 24" long.   I estimated it was 5kW.

So I went over to the soldier overseeing it and asked him if it was 5kW....   I was shocked when he told me, "Nope it's 50kW"  Seeing the surprise on my face he quickly added, "It's 400Hz".

Wow that was slick.   If utterly useless. :)

RE: Depth of water sensing

The 'NET' is approaching the next milestone: 250

I wouldn't call any small turbine powered device 'useless'.

Dispose of the 400Hz genny (not even a good anchor) and install the turbine into your inboard speed-boat. Impress the neighbours and thrill the children.

RE: Depth of water sensing

Nah I doubt that turbine had enough torque to drive a boat.  Better to have it power an electric boat motor. (something i've always wanted to do.)

Hey smoked, how's that Goodman holding up?  Good heat, no failures?  We're thinking of buying several for own house and properties.

RE: Depth of water sensing

Well how's it holding up...

I has run probably 1.5 hours total.  But it has greatly improved the comfort around here and the only thing I stuffed into the fireplace so far is the Christmas tree.

It has already had a failure....banghead

The control transformer spazzed out.  It started humming so loudly that my better half had to call me at the office. I think the lamination had a problem but that is just a guess.  So I figure what me worry? Simple straight forward warranty problem... WRONG!!! Upon actually attempting to find and work the warranty I discover I must fill out some PDF.  Once I find it and read it.. it completely disavows Goodman from any warranty claims if the unit wasn't installed by a dealer.  What a bunch of crap!  How could a non-dealer installation cause transformer windings to fail in a few hours?!?!?   The jerks.

So if you are going to install them yourself beware.  If some licensed installer is going to do it then that's not a problem.   Other than that it runs well.  I ended up using the 40VA transformer that ran my old furnace' igniter.  

RE: Depth of water sensing

What is it all about? Has everything been said? I have nothing to add. Just that I try to be answer number 250...

Gunnar Englund
www.gke.org

RE: Depth of water sensing

Congratulations.
1/4 of the way to a kilopost.

Anymore for anymore?

"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams

RE: Depth of water sensing

I emailed Heat+Cool U and they said they will honor the warranty if Goodman won't replace a part.  Guess u bought from the wrong place. ;)


A kilopost eh?  Of course u mean 210 posts, right.  We need 4 more after this one to reach the quarter kP point.

--
There are 10 kinds of people in the world, those who understand binary, and those who don't.

RE: Depth of water sensing

Interesting... That place never came up in all my searches.
I don't see the furnace I got in their list but they could probably get it.

RE: Depth of water sensing

(OP)
Just an update.  I will post this to the variable speed pump thread also.

Grundfoss just announced exactly what I needed.

A circulator with a PM motor, built in speed control, and pressure sensors to control the head across the pump.  The timing sucks.

RE: Depth of water sensing

(OP)
Hi Keith

Yes, that is also my thinking. Shure would like to try one.  But I suspect Grundfoss is not going to provide one to test.  Last time I got information from my contractor, Grundfoss had the old pumps (original and one they told us to buy to test) but never actually reimbursed the contractor for the two rather expensive returned pumps.

If they actually have one for sale at this time, I am guessing it is going to be in the $600 - $1000 range.  Just not going to do it now.

RE: Depth of water sensing

Yeah alternety, I understand.

Besides you are probably used to the sound by now.laughtears

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

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