[RMcNeal]

I have found that the heat pump will actually help and circulate heat well into the 20's if you supplement it with the fireplace heat and/or a ceramic heater inside. We've been down to the teens and 20's with only the heat pump, fireplace and a small ceramic heater. It's able to keep the entire coach at 69 degrees. I do recommend that you monitor temps in your underbelly and basement to prevent freezing pipes. I purchased a thermometer with 3 remote sensors and put one in the underbelly, garage and pass through basement. Temps remain 48 and above down there so no problem with freezing pipes.