Andrew Meulenberg <mules...@gmail.com> wrote: At low external temperatures, many heat pump systems switch over to ohmic > heating. >
I had one that did that at ~40 deg F, here in Atlanta. Which is not very cold. I think more modern ones go lower. An online source says they go down to 25 deg F. Mine did not have an ohmic heater. It had a conventional natural gas furnace. An auxiliary furnace. The cheapest model available, because it was not used often. I think that is the normal configuration. (Actually, I had two heat pumps for reasons beyond the scope of the discussion. Still have one.) Do they turn off the heat pump or do they heat the input to the pump? > The heat pump definitely goes off. I could see the outdoor compressor stop. The conventional heater takes over.
