I've had a heat pump failure and have had two techs look at it. Tech A says it's a bad reversing valve. Tech B says it's a bad compressor.

Tech B says is can't be a bad reversing valve, because when those valves fail, they fail either in the heat position or the cool position, or a bi-flow position (in the middle). In all three cases, he says, there should be a change in the coolant pressure when you start the compressor, if it's working.

Tech A says that in the bi-flow failure mode there will be no change in pressure when you start the compressor, even if it's working.

Who is right?

Thanks,

Steve

It does not make a difference who is correct. The problem you have is choosing between two servicemen. I would call a third person to check both of the others estimates.

In all cases there will be some kind of change in the pressure upon start up.