Pentair Ultratemp - Bad Capacitor & Low Refrig Error

[Cetanorak]

Tried to use our Pentair heat pump for the first time this year and it's throwing a "Low Refrig" error shortly after starting up. Had a Pentair technician out today who tested everything and the only sign of dysfunction that he noticed was the main capacitor was testing out of spec, although the unit successfully heated and cooled the entire time he was here (of course!). The quoted price for the capacitor was $400+ plus labor so I told him that I'd see about locating the capacitor online and installing myself (hopefully it's easy enough).

Does anybody have experience with this "Low Refrig" alert? Refrigerant pressures tested fine, no leaks, low pressure switch was good, fan runs at expected speed. Is it possible that a failing capacitor would cause a "Low Refrig" alert?

 

[JoyfulNoise]

Tried to use our Pentair heat pump for the first time this year and it's throwing a "Low Refrig" error shortly after starting up. Had a Pentair technician out today who tested everything and the only sign of dysfunction that he noticed was the main capacitor was testing out of spec, although the unit successfully heated and cooled the entire time he was here (of course!). The quoted price for the capacitor was $400+ plus labor so I told him that I'd see about locating the capacitor online and installing myself (hopefully it's easy enough).

Does anybody have experience with this "Low Refrig" alert? Refrigerant pressures tested fine, no leaks, low pressure switch was good, fan runs at expected speed. Is it possible that a failing capacitor would cause a "Low Refrig" alert?

Possibly yes. If the cap is failing the compressor may not have started properly and the pressure error was thrown.

Replace the cap yourself. They literally cost $30-$50 and it’s a 10min job. Just make sure you mark the wiring and that you do all the work with the power disconnected. To be safe, after the power is switched off, use a metal screwdriver with a rubber handle to short all the capacitor terminals to discharge the old cap. Also, make sure that the new cap you purchase matches the specs of the old one exactly and that the operating voltage of the new cap either meets or exceeds the old one.

 

[Cetanorak]

Replaced the capacitor and it does seemed to have resolved the issue.