The three most common residential heat-pump failures are:
1. Capacitor Failure (Electrical)
These wear out sometimes, but usually fail due to electrical issues cause by the power company and stop the compressor or fan from starting.
2. Refrigerant Leaks
Low charge from small leaks leads to poor heating, freezing coils, and eventual compressor damage.
3. Physical Damage
Sometimes a fuckin tree lands on your Heatpump.