I have a Comfortmaker haet pump that keeps frosting up. I don't think the unit is automatically kicking in to defrost and the repairman says it's supposed to be frosted.
The repairman came out and said it wasn't defrsoting because it was low on Freon so he charged it. The next morning, the unit was a little frosty as the temperature got down to about 38 degrees. I called him back out and he said that was normal. Last night got to be about 30 degrees and I woke up to a frost heat pump (see picture). When I called the service company back, they said it's supposed to be frost and that I should always turn on my emergency heat when I expect the temperature to fall below 40 degrees.
My neighbor has an electric heat pump and never uses emergency heat and his unit is never forst.
Looking at the picture, does this look normal? It only seems like it defrosts when the temperature outside rises.