Why Chilled Water Supply Temp = 7C?
Why Chilled Water Supply Temp = 7C?
(OP)
Hi All,
A lot of people are using the rule of thumb for chiller design, Chilled Water Supply = 7C, and Chilled Water Return = 12C. Why is that the case? I heard this can be explained using the psychrometric chart. Please advise.
Thanks in advance.
MM.
A lot of people are using the rule of thumb for chiller design, Chilled Water Supply = 7C, and Chilled Water Return = 12C. Why is that the case? I heard this can be explained using the psychrometric chart. Please advise.
Thanks in advance.
MM.





RE: Why Chilled Water Supply Temp = 7C?
Without checking, I am assuming 7C and 12C corrispond to 45F and 55F.
RE: Why Chilled Water Supply Temp = 7C?
http://www
Click on http
for an adobe interactive tutorial which covers using psychrometric charts. (It takes a few seconds to load though)
They've got a lot of good information on other engineering stuff too!
Best of luck!
RE: Why Chilled Water Supply Temp = 7C?
Further, that is about the safe temperature a chilled water system can maintain. Generally, you shouldn't go below 50C and you are safe with an antifreeze thermostat setting at 60C.
Incase of trouble, you can reduce the temperature to one more deg.C(say, during high latent load conditions).
etc.etc. I hope somebody else will come up with some more points.
Regards,
RE: Why Chilled Water Supply Temp = 7C?
Studies have shown optimum temperature rise is 14, 15°F instead of 10 for economy of pumping & pipe sizing.
RE: Why Chilled Water Supply Temp = 7C?
RE: Why Chilled Water Supply Temp = 7C?
In my office chilled water system, the Return CHW temperature is being used for control of the chillers. I find it strange. Do you think we should change to regulate the Supply water temperature instead of the Return?
RE: Why Chilled Water Supply Temp = 7C?
If the return water is coming back warm, then the system needs more cooling and the chiller will send out colder supply water.
So supply and return water temperatures need to be monitored by the chiller.