Heat pump defrost control board and thermostat reversing valve voltage level

[bcohen2removeme]

Thanks!. This is exactly the information that I was looking for.

• I disconnected the orange wire from the thermostat and turned on the heat pump.

• It put out good heat and the voltage at the disconnected orange wire was 26V.

• About ten minutes later, I heard the swooshing sound of the reversing valve and the unit began to blow cold. The voltage at the disconnected orange wire at the thermostat read 0V.

• The heat pump continued to blow very cold continiously (longer than 30 minutes) and I climbed on the roof and checked the unit. The external fan *is* running.

• I'll see if I can figure out where the oragne wire at the condensing unit is.

Thanks,

-Ben

[Bob]

I think you should recover the refrigerant charge and replace the reversing valve, or call the tech back to see what he thinks.