Low Supply Air Temperature
Low Supply Air Temperature
(OP)
If a person requires a data room to be 60-65 degrees instead of around 70 degrees, how would this be achieved? The equipment load is constant and there is no wall loads because room is inside building. If the supply air temperature is decreased, this should increase the AC required? If using the formula for BTUH=1.08xCFM(deltaT). The delta T is the same whether it is 75-55 or 65-45. Am I running into a thermodynamic problem with the refrig? Am I using the wrong formula?





RE: Low Supply Air Temperature
If one side of a wall is colder, then you do.
Do you really have no latent heat to deal with at all?
RE: Low Supply Air Temperature
RE: Low Supply Air Temperature
You're looking at around 25ACH to get 65F indoor.
RE: Low Supply Air Temperature
Doing 60F space temp can get you into the frosty-coil area pretty easily, ruining the reliability that the cold temperature was supposed to enhance.
Look at info from APC, how to design air flow through data centers / hot aisle, cold aisle concept, spot cooling solutions, etc...
Good luck with it! Let us know how it works out.
Goober Dave
Good on ya,
Goober Dave
RE: Low Supply Air Temperature
RE: Low Supply Air Temperature
I actually assumed the average office space of 9-foot ceiling.
Model it on Trace or E20-II, just lock in the supply air at 53 to 55F.
RE: Low Supply Air Temperature
For air changes go here: http:
RE: Low Supply Air Temperature
However, in fact though you've created 'partion' loads as each of the four walls, the ceiling and the floor are now sources of heat from adjacent rooms kept at warmer temperature.
Fortunetly, the temperature differential is quite low. A typical uninsulated partion wall has an R-value around 2. Your temperature differential is 5-10 deg F your area is your walls is a known.
For 1000 sqft of wall this works out to be 10,000 to 20,000 Btu/hr. I'm guessing the extra 1-2 tons of cooling isn't going to make a huge difference compared to the diversity of the servers.
If you are tight, you could insulate the walls.
One other thing to watch is that you will have colder walls on the outside of the server room. Depending on your design conditions you may want to think about condensation.