OK, here's the scenario... 10 yr old 20Ton Carrier package heatpump, 2 stage cool/heat, 2 compressors, cap tube system.
On circuit 2, reversing valve failed for 3rd time in 10 yrs - stuck in Cooling position. Circuit 1 has gone thru 2 RV's in lifespan. No compressor failures in history - don't suspect contamination. What a PITA to change - you have to be a contortionist!
So, any ideas on why these RV's are failing every few years? Could it be a piping design flaw? The RV's are very close to the compressor discharge valve. They are factory mounted in a horizontal position. These are pilot operated valves - could a low discharge pressure prevent the actuation? When checked it was runnning 175psi.
Thanks for your input!