What's wrong with this picture?
What's wrong with this picture?
(OP)
One star for the obvious and two stars for the not so obvious with an explanation.
Regards
Dave
Regards
Dave
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What's wrong with this picture?
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RE: What's wrong with this picture?
RE: What's wrong with this picture?
Sorry, nope and nope.
RE: What's wrong with this picture?
This might be a limited area system off a domestic water system.
The upstream valve might be closed since the sprinkler system has not been tested yet and the domestic system has water in it.
The expansion tank is being used to compensate for pressure increase in the downstream sprinkler piping - although why it would be needed is uncertain.
RE: What's wrong with this picture?
RE: What's wrong with this picture?
The backflow prevention device is also a RPZ (reduced pressure zone) style which is designed to dump water from the middle bottom port when a backpressure event occurs; there is not drain piping on this RPZ.
It also looks like the sprinkler head has been leaking based on the rust under the head and relatively new steel pipe upstream and downstream.
The white tank appears to be some sort of an attempt to trap air in the system piping? Is that an air line connection controlled by the red handled valve with a check valve between the white tank and the system piping?? Looks like someone tried to install a dry system with no air compressor..........maybe the air kept on dumping due to higher pressure on the downstream side so they flipped the backflow device to resolve the problem! HA HA
The only other possible problem I see is that the system does not have a low point drain.
I am fairly confident this sprinkler system deserves a RED TAG (primarily due to the oreintation of the RPZ Backflow prevention device)!!
RE: What's wrong with this picture?
Dave
RE: What's wrong with this picture?
RE: What's wrong with this picture?
Dave
RE: What's wrong with this picture?
RE: What's wrong with this picture?
Dave
RE: What's wrong with this picture?
Not sure but don't expansion tanks need to be mounted vertically?
RE: What's wrong with this picture?
RE: What's wrong with this picture?
If this is a glycol loop, where is the fill cup? I suppose that you could use the 1/2" ball valve after the expansion chamber to fill the system with antifreeze.
Also shouldn't there be another isolation valve on the discharge side of the backflow for servicing or is it there before the gauge and I can't see it because of the orientation of the picture?
RE: What's wrong with this picture?
RE: What's wrong with this picture?
*If* you do one the *right way*, with a UL listed expansion tank etc, putting in a small dry pipe system would be nearly as cheap while saving the customer headaches every year forever.
I don't do anti-freeze loops and haven't for 15 years.
RE: What's wrong with this picture?
Can you give some more background on that SD2? We use an anti-freeze loop on just about every project we work on. I'm located in Canada, and the majority of the use is small zones near overhead doors.
For us, it's a lower maintenance solution than a dry pipe zone, fewer pipe corrosion issues than dry pipe... generally cheaper too.
RE: What's wrong with this picture?
I'm near Florida so it's warmer and seeing how it seldom gets below freezing we don't have to fret aver zones near overhead doors. Coldest I've seen it in past 4 years was 24 F and that was cold enough for me.
When I do see anti-freeze systems they tend to be larger than one or two heads.
The cost of an RPZ backflow prevention assembly (EPA required here) plus added to the cost of the expansion tank adds to the cost along with the anti-freeze at $10 per gallon etc.
Annual testing on the backflow will run $100 per year (must be done by someone certified in testing backflows and sprinklers) and that goes on forever. Add to this the cost of draining/re-mixing the anti-freeze and I wouldn't touch the smallest one for less than $250 per year total. This goes on forever.
Yes, they are cheaper but I'm opinionated and don't like them.
RE: What's wrong with this picture?
I'm "up here" also. The first example above is 3 sprinklers protecting a small loading bay of a grocery store, the other is 12 sprinklers at the entrance to an underground parkade. I would say that a dry system will cost significantly more initially, most certainly if you have to have a dedicated compressor. But then as SD points out there's the ongoing maintenance costs....
Personally I can't stand the stuff.
Dave
RE: What's wrong with this picture?
RE: What's wrong with this picture?
Dave
RE: What's wrong with this picture?
RE: What's wrong with this picture?
Just as a side note. Most of the water districts in our area are accepting glycerin in the anti freeze without the addition of the RPZ as it is food grade and does not pose a threat to public health.