Heat Pump Sump Heat
brad_rh
| Posted in Mechanicals on
My American Standard heat pump has a sump heater that runs quite a bit. I turned the unit off at the breaker last spring. There are many cold days & nights when I don’t need the heat pump. I’m wondering if there are any issues leaving it off? Should I turn it on xx hours before I need the heat pump? The service manual says the sump heat is ON When outdoor temp is below 80F and compressor dome temp is less than the outdoor ambient temp. That seems pretty wasteful.
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Replies
Refrigerant migration can be a serious lubrication or flooding issue. It might need 4-48 hours of heater operation before operating to drive it back. If the manual doesn't specify, I'd use 12+ hours.
Not clear how this issue is handled when power is returned after a power outage. I suspect many heat pumps experience shorter than expected life.
I think if you turn on the breaker two to three hours before you need to run the unit, it should be fine. Just need enough time to heat the pan and oil in it up.
It is annoying that manufactures don't have better controls for these, waste of energy. Similar issues with drain pan heaters on some mini splits.