My microwave/convection oven is on a 15 amp breaker. Usually 14 gauge wire is on a 15 amp breaker in residential and commercial applications. 20 amp breakers protect 12 gauge wire. The heat pump won't pull as many amps in the winter as it does when it's hot out. The refrigerant will be a higher pressure then and will make the compressor running amps run closer to the listed full load amp rating. 15 amp breaker may not work for it in the summer.
2016 Forester 2401WS MBS
Life is short...eat the cookie