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nevinjohn
24-03-2017, 07:12 AM
Hi,

I'm designing couple of fresh air units for some class rooms. Since the capacity (air requirement) is limited, I need to go for ceiling suspended fresh air units, preferably VRFs.The ambient here is 47DBT/35WBT as per clients design standards. I spoke with many VRF vendors, where they told me that their equipment, a.k.a OUTDOOR UNIT is designed for 54deg C. Thats a good thing for me, however the ON COIL temperature for INDOOR UNIT is only at 43/35 deg C.

I did the psychometric load calculations to determine the indoor unit size considering on coil @ 47DBT/35WBT and off coil @ 21DBT/WBT. My question is, whether can I rely on these indoor units?

Lets say, I derived at 3TR @ my design temperature, would it deteriorate @ vendors (lets say Daikin's) off coil temperature? I believe @ vendors offcoil, it should still be able to give me 25 deg off coil??

Thanks!
Nevin.