valhalla360 wrote:
DrewE wrote:
hypoxia wrote:
Golden_HVAC wrote:
When it is less than 40F outside, then the heat pump thermostat will change over to the propane furnace.
Do all RV heat pumps switch the heat pump off around 40? All I have in my stick house is a heat pump which works fine on the few days we get in the 20"s.
Most house heat pumps use the ground as the heat source/sink, while RV units use the outside air. Underground temperatures are much more constant and (if below the frost line) do not get below freezing even when the outside temperature is bitter cold.
I think you are confusing geothermal systems (which use a heat pump) with standard head pump systems.
Most household heat pump systems use the exact same principals as an RV heat pump will. Essentially they work as an air conditioner in reverse and they also suffer in very cold weather as the air has little heat to give up.
A little research, and I see that you are entirely correct. :S
I think my confusion stemmed from the fact that pretty much the only heat pump systems that are installed in Vermont are geothermal ones, as winters have prolonged sub-freezing temperatures. (The geothermal systems are relatively rare, I suspect due to the costly installation. Most people burn something.)