Heat pump outside unit will not turn on by its self , must be turned off and then turned on again?

Question

fan unit continues to run but outside unit will not turn its self back on

Answer 1

you have a voltage problem either low or high voltage check your breakers first then see if you have low voltage going outside to contactor it could be low voltage wire or contactor itself or t-stat gl

Answer 2

There is a single pole relay that when energised pulls one leg in to start the outside unit. If nothing ay all comes on outside your loosing the 24 volt signal or the relay is bad. Check the two low voltage wires when the thermostat is set to come on, there should be 24 volts. Can be just a short so make sure you have good connections in the wirenut. The same 24 volts that brings the fan inside on turns the outside unit on. Thanks, Kevin. HVACRR Tech, 15 years