Supply Air Temp

[weather777]

Could some one please tell me how to determine what the supply air temperature should be in heat pump mode when the outside temperature is 40 and the room temperature is 57---I.E. heating the house up in the AM from an initial 57 degrees to 65 how warm should the air from the register be---seems to never get above upper 70's.

Thank you

[geno54]

A Ballpark figure is about 20 deg. on the heatpump only with no strip heat on. This may vary up or down from one manufacturer to another. I always inform my customers not to set back there tstats on heat pumps more than a few degrees. At your temps the air will feel cool most of the time.

[jimbo]

A 15º to 20º delta T is about all you can expect. Some systems will kick in the electric heat when the delta between set point and room temp is large, just for this comfort reason. Your system or T-stat may or may not have the capability to do this. Have an HVAC guy look at it for you.

[weather777]

Thank you very much---