Jeff most H/P are set up on a 2*f lag in the T-stat. If heat pump fails to come on or cant keep up it will fall back 2*f on the stat and the electric or auxiliary heat will come on so you don't lose all your conditioned air in the house. Ok so why isn't the H/P coming on first you must have a 24v signal to bring the unit on.That seems good because the stat is bringing the aux heat on. A service person should be called/ some possible problems, Low pressure switch lockout. Failed contactor, no line Voltage. I recommend a service call anything past the T- Stat. Hope this helps.
Answers & Comments
Jeff most H/P are set up on a 2*f lag in the T-stat. If heat pump fails to come on or cant keep up it will fall back 2*f on the stat and the electric or auxiliary heat will come on so you don't lose all your conditioned air in the house. Ok so why isn't the H/P coming on first you must have a 24v signal to bring the unit on.That seems good because the stat is bringing the aux heat on. A service person should be called/ some possible problems, Low pressure switch lockout. Failed contactor, no line Voltage. I recommend a service call anything past the T- Stat. Hope this helps.