[cwestl]

I can see we don't have any AC Guys in the forum. Any heat pump will ice up the outside coil while heating. Same with you home unit if you have a heat pump. Sensors will sense this condition and put it in a defrost mode to melt the ice off the coil. Then it should go back to heating. Of course Home heat pumps will work below 32 Deg. Of course the units on Travel Trailers have a lot smaller coils and are not as good collecting heat from outside air.