I just finished a complete geothermal install. This issue is kicking my butt. This system has a single stage compressor with 15 K of thermal B/U heat.
The Tstat is a WF model TP32U03 3 stage heat 2 stage cool.
My question is: The aux heat turns on at 3 degrees above room temp. The aux heat will not turn off until the tstat room temp setpoint is satisfied and the heat pump shuts off. Is this aux heat "turn off" a function of the tstat or the WSHP mother board? I tried programming the tstat, I can get the aux heat "turn on" temp to be delayed until 7 degrees above room temp vice 3 degrees, but the aux heat still stays turned ON until the tstat\room temperature is satisfied. Shouldnt the aux heat turn off within 2 degrees above the tstat (room) temp? Is this normal operation for some tstats?
On another note, on this single stage compressor system, Y2 heating just bumps up the speed of the X13 ECM motor a little bit. What is the purpose\gain of that? I mean, if I'm losing heat in the structure calling Y1, why would I want to add AHU cfm without additional heat?