I have a Lennox heat pump unit and it will only run for about 3 minutes before the breaker on the unit trips,, What could cause this and how can it be fixed,,
Rickey

Breaker tired or worn allowing it to trip at a lower rate.

Unit overcharged with refrigerant.

Unit undercharged with refrigerant.

Comperssor drawing to many amps causing the breaker to trip. Usually the compressor is defective.

Bad or out of range run capacitor for the copmpressor.

Most of this will need a professional to diagnose.