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thrashme
06-19-2011, 08:46 PM
I have periodically had some borderline high humidity levels 60%rh Max in a couple of areas of a building. The temps required are 60-65 degrees F, 40-60%rh. System is Trane Intellipak, varitrac VAV's and Tracer Controls. I just took over this account and am wondering about adjusting the SA setpoint. Any ideas?
duke of earl
06-19-2011, 09:35 PM
60-65 in the space is approaching dew point. You need a system that has a dehum mode with some kind of reheat on it to get these kind of space temps and maintain the desired rh. The scroll compressors won't last long with such low return temps.
hvac n-j-near
06-20-2011, 12:43 PM
60-65 in the space is approaching dew point. You need a system that has a dehum mode with some kind of reheat on it to get these kind of space temps and maintain the desired rh. The scroll compressors won't last long with such low return temps.

Ditto what DoE said. Very difficult to reach those conditions with regular DX (or standard chilled water) equipment!
Jarreau
06-20-2011, 05:41 PM
To reach 65° and 45% you would need ~43° leaving air temp, which will be difficult to do if the Trane Intellipack is simply a stock machine. This type of application is doable but requires hardware specifically designed for that type of duty.

J
superfittertech
06-21-2011, 10:24 PM
60 -65 degrees? Is this a lab or is it a server room? a lot of I T guys spec those temps, because they want a cushion. If this is the case tell them it should be 69 -70 degrees and talk to them about possibly installing a backup unit.
herohero
06-23-2011, 10:38 PM
To reach 65° and 45% you would need ~43° leaving air temp, which will be difficult to do if the Trane Intellipack is simply a stock machine. This type of application is doable but requires hardware specifically designed for that type of duty.

J

I think the supply air temp need to be lower than 43F, because RSHR of the room. With this kind of requirement, I think Trane CDQ is suitable.
thrashme
06-23-2011, 10:45 PM
This is a Surgery Center & the 3 rooms are OR's. Typically it does this with no problems. Actually though I had a bad humidity sensor. At he time of the post, I had been to the job, but was unable to enter the room. The following day, I checked it and it was off 10+ % too high. Currently, the SA setpoint is 50 Degrees F.