Heat pumps won’t start

[mike2]

Both our roof heat pumps won’t start. It’s 39 in the trailer heat pumps are set to 67 I can hear them “click “ when I switch from auto or low or high both won’t start plugged into my home 30amp. Only run one at a time. They always worked before now neither one will run. What am I simply overlooking?

[overlander63]

They won't turn on if the outdoor temp is below 35-40. How cold is it outside?

[Adventure.AS]

What is the outside temperature?

[mike2]

Originally Posted by overlander63

They won't turn on if the outdoor temp is below 35-40. How cold is it outside?

Sorry for the delay... thanks, yes it was in the 30s and high wind so windchill was even lower. I’m glad it’s programmed like that and not a issue. Thanks for your response

[mike2]

Sorry it was in the low 30s plus wind

[jcanavera]

Yep there is a point of diminishing returns where a heat pump will no longer be able to extract enough heat from the outside air to give you adequate heat discharge.

The other thing is that those outside coils that usually are hot in the summer, exhausting the heat from inside the trailer are now cold instead. Depending upon the outdoor humidity the outside condenser can form ice. That's why most heat pumps go into a reverse mode after a certain amount of run time, to clear the ice off the outdoor coils . In extremely humid situations and colder out door temperatures, there also is the possibility of the defrost cycle not being long enough and your coils may ice up. We had this happen in Branson once on a cold rainy day. We came back to the trailer and found the trailer cold inside. I went outside and noticed the outdoor coils were completely white with ice.

Jack

[guskmg]

Shouldn't the furnace come on when it is too cold for the heat pumps? Mine does.