Have a sub panel in garage with 50amp gfi breaker that is connected to a pool heat pump. It intermittently trips and did some diagnostics. After testing all the heat pump stuff, I disconnected the heat pump, let the wires free and it still trips. Tried new breaker, and still trips. Is it the wire under ground. It worked fine all year long last year and all spring, just 1 week ago did this start. It's a 6/2 wire.... Red, Black, Ground.... this is per Hayward heat pump specs.