Chilled water GPM ?
Chilled water GPM ?
(OP)
Hi,
I need help on the job. I have three chiller barrels that are between and parallel to main return and supply chilled water (no brine). Each parallel loop has a proportional two way valve. One valve is closed and two are open. Main pump (only one pump) has a 5/8 load. Up at the top (the highest point of the loop) of the main return loop there is a hand butterfly valve then a large storage tank with W.M... This loop is an open loop, and it’s open at the tank. Ok here is the question: Why is it that when the hand butterfly valve is 40 % closed the GPM goes up? I know you need more input, sorry I am just looking for a place to start.
My thoughts: first I am going to check flow meter. I think GPM increases because supply psi increases causing trapped air to reduce.
Your thoughts on this will be greatly appreciated.
Thank you
Logmode
I need help on the job. I have three chiller barrels that are between and parallel to main return and supply chilled water (no brine). Each parallel loop has a proportional two way valve. One valve is closed and two are open. Main pump (only one pump) has a 5/8 load. Up at the top (the highest point of the loop) of the main return loop there is a hand butterfly valve then a large storage tank with W.M... This loop is an open loop, and it’s open at the tank. Ok here is the question: Why is it that when the hand butterfly valve is 40 % closed the GPM goes up? I know you need more input, sorry I am just looking for a place to start.
My thoughts: first I am going to check flow meter. I think GPM increases because supply psi increases causing trapped air to reduce.
Your thoughts on this will be greatly appreciated.
Thank you
Logmode





RE: Chilled water GPM ?
http://www.eng-tips.com/viewthread.cfm?qid=328800
RE: Chilled water GPM ?
thank you for your response.
I do not understand why you would want me to read something that will not answer my question.
I have read what you asked of me to read. trashcanman and chasBean gave a great response and I agree with them.
If I gave an answer to Nicole, it would have been: I think Your GPM has increased with pressure increase, and if so why? (Sounds like what I am asking about)
Is that why you wanted me to read this?
or
Then there TTFN basically read the rules. Was that your point?
or
(nicole10g (Electrical) However, I am interested to know if there is no expansion tank connected (literally) but with the bypass valve open, what untoward impact will it happen to the aircon system that I should take note? ) She received no answer, ignored! I would guess the reason she was ignored is because they felt it would take too much time and they needed more facts. Is this the reason why you wanted me to read that post?
Where am I to go with this?
Thank you
Logmode
RE: Chilled water GPM ?
Best, CB
RE: Chilled water GPM ?
I don't think you understand the problem, either and should get an Engineer to give you some help.
RE: Chilled water GPM ?
RE: Chilled water GPM ?
RE: Chilled water GPM ?
RE: Chilled water GPM ?
RE: Chilled water GPM ?
RE: Chilled water GPM ?
Best to you,
Goober Dave
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RE: Chilled water GPM ?
- three parallel chillers, only two of them are in service at any time.
- these chillers feed a main supply line
- this line end up with valve and storag tank, ( I didn't understand what is W.M ...?
- you have one pump only in this system, but Also i didn't understand what is" pump has 5/8 load"?
- you have a return pipe connects the storag tank with pump suction.
- you observed that when the valve before the tank is closin the GPM increase.the questions are:
- at which point did you meeaure the GPM and how?
- is this tank is open to the air
RE: Chilled water GPM ?
Thx for the thought. :)
- these chillers feed a main supply line
Yes
- this line end up with valve and storag tank, ( I didn't understand what is W.M ...?
Yes this return line. W.M. is water make up.
- you have one pump only in this system, but Also i didn't understand what is" pump has 5/8 load"?
(a) Yes one pump
(b) When a pump is running there is a load on it. This pump has a 5/8 or the correct way is to say 62.5% load on it.
- you have a return pipe connects the storag tank with pump suction.
Yes
- you observed that when the valve before the tank is closin the GPM increase.the questions are:
- at which point did you meeaure the GPM and how?
(a) First A/H on the loop. This A/H is the closes to the chiller.
(b)The first A/H on the loop has a G.P.M. gauge.
- is this tank is open to the air
Yes
Thank you
logmode
He who is often reproved, yet stiffens his neck, will suddenly be broken beyond healing.
RE: Chilled water GPM ?
what about the 37.5% of pumping load from where does it come?
- you are checking the flow at a point which is not on the main pipe, it is on the A/H branch pipe, so if the flow increase at this branch it would be decrease at another branch because when you close the valve you are changing the system resistance
you need to measure the flow at the pump discharge to say it is increasing or decreasing.
- your tank has a make up water, which is not chilled water I guess, that tell this is a kind of process, then you say this system is connected A/H which is HVAC, if A/H means an air handler, what kind of system do you have?
RE: Chilled water GPM ?
RE: Chilled water GPM ?
logmode
RE: Chilled water GPM ?
TTFN
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RE: Chilled water GPM ?
thank you.
RE: Chilled water GPM ?
it could be a school or anything or even a homework, if you don't know how to respect people here so don't ask and save your time.
RE: Chilled water GPM ?
moreBy the way a answer of some kind or even a thought of a possibility would be greatly appreciative.
hugmode