Re: Chilled water pressure
Hi Ghaz,
Not personally, what was the application, was it process cooling for some sort of machinery?
Cheers
Re: Chilled water pressure
It was aircon for offices
Re: Chilled water pressure
How tall was the system (building height)?
Re: Chilled water pressure
It takes 12psi to push a column of water up 28ft. It takes 120psi for a 280ft high system.
If this minimum pressure is not maintained, there will be a vacuum at the top causing all sorts of air lock problems.
Being non-scientific, I just figure out the height of the building and divide by 2. This gives me a little extra.
Re: Chilled water pressure
Quote:
Originally Posted by
Gary
It takes 12psi to push a column of water up 28ft. It takes 120psi for a 280ft high system.
If this minimum pressure is not maintained, there will be a vacuum at the top causing all sorts of air lock problems.
Being non-scientific, I just figure out the height of the building and divide by 2. This gives me a little extra.
Thanks Gary
That is a useful tip!
Grizzly
Re: Chilled water pressure
Indeed having a 110 psi chilled water supply pressure is too high based on my experience in plant aircon chillers. What is the TDH requirement of your chilled water pipeline loop?,or better yet check the chilled water return pressure or the suction pressure of the chilled pump near the chiller,the pressure should be in the range of 20-25 psi to be able to have good chilled water recirculation as well as minimize pipeline leaks brought about by high pressure within the pipe loop.
Re: Chilled water pressure
Hi GHAZ
Gary is right. I must assume the pressure was at the bottom of the building. You can get high pressure chillers for locating at the bottom of a building but they are not common.
Re: Chilled water pressure
hi its a 4 storey high building and the water pumps are in the basement
Re: Chilled water pressure
Thanks GHAZ
That pressure doesn't sound out of the ordinary. Other considerations would be on a cooler day most of the chilled water valves would be shut, if installed the chilled water bypass valve may not be callibrated correctly to maintain the required system pressure differential, and most chillers would have around 20 to 60 psi press drop through the coooer, or the pump coud be oversized and the butterfly valve could be backed off to minimise cavitation.