I need some forum help. I installed a Pentair Thermalflo heat pump and have been trouble shooting since it was first turn on. I will try to keep my narrative short while including what has already been done.
The error code that shuts down the unit is "high refrigerant pressure." I researched this on TFP and other open source media. I had an HVAC tech check my refrigerant levels. The gauges showed the heat pump high pressure switch was breaking the 24 volt current when pressure reached 450. The tech said it should be around 300. Thus, my water flow through the coils appears to be too week to keep the high pressure switch from tripping. My GPM flow is between 50 and 75 (which is within proper range for my unit). I do not have a air leak on the suction side. My clean filter pressure is 15psi.
I used a drain bladder and blew out the coils (in case something made it's way into the heat pump coils and was restricting water flow). That didn't help.
Could the internal check valve be somehow broken? That is pretty much all that is left for me to inspect. If the check valve is letting too much water through it, then I suppose it could relieve water pressure and flow through the coils.
How could I tell? If it is broken, then how do I fix it? The check valve is plumped into the OEM pipes connecting the unions to the coils.