Have HVAC Questions? Ask an HVAC Expert for Answers
Give me model on thermostat and lets start by checking proper wiring and setup there..Tell me what wires connect to what terminals at thermostat
Wiring sounds good. Next verify the O/B switch is set to O
OK that is all good.Do you have a volt meter?
What we need to do is see if we are getting 24v at the reversing valve solenoid in heat mode.
Since the unit energized reversing valve in cool mode, there should be o voltage at solenoid in heat mode.
I understand.Often it is something simple like a wire in wrong place.Beyond this we would need tools to troubleshoot.