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seban
May 23, 2007, 09:42 PM
Hi,
I am new in this site.
Can anybody tell me how the relative humidity works in a recirculating AHU.
My indoor air temp is 24deg, 50% RH. When I cool this air to 13deg. Centigrade the RH is becoming 100%. Can I use this 100% RH air directly to space or do I have to use reheating to reduce th RH. When I reduce the RH, the supply temperature is becoming 18deg. Or 20 deg. Is it recommended.

Thanks

Stratmando
May 27, 2007, 10:21 AM
Don"t know if this will help, and not sure of "To Space"? But...
Warm Air holds more moisture than cool air, when it is cooled it "Drops" Out of Air Handler
Drain.
In weather, when warm moist air hits cool or cold air it drops(rain).
When you are cooling, you are reducing Humidity.
We get 15 gallons per day, we use for plants.

seban
May 28, 2007, 03:31 AM
Hi Sir,

Thanks for the replay.
I agreed this. But still I have some doubts, that when the off coil temperature of AHU is 13deg and the RH will be 100%. Can I supply this air to the space without any reheating. If yes, Why people are using reheat coil or sensible wheel in FAHU to reduce the humidity. Normally what will be the comfort condition of moisture content in the air for a space.

Stratmando
May 28, 2007, 06:08 AM
A Good AC man could probably explain, You will probably get answer shortly.
I don't understand, but reheat coil and cooling seem contradictory, I'm sure it makes sense, I just don't understand. Hope I didn't waste you time. Good Luck.
Take Care