HVAC problem, need help

[SabreKiller]

The outside fan unit to my heat pump had frozen up for some reason. I can hear it humming. I try to move the fan with a stick and it won't budge. Any ideas?

I do have an HVAC repair guy coming out.

[Ttechhunter]

Capacitor

[thegrouse]

Are you sure that it is not stuck in defrost mode? If it is a heat pump when it goes into defrost the fan motor is supposed to shut off while the compressor runs. When it is this cold the heat pump does not work real well.

[SabreKiller]

Are you sure that it is not stuck in defrost mode? If it is a heat pump when it goes into defrost the fan motor is supposed to shut off while the compressor runs. When it is this cold the heat pump does not work real well.

I've never heard of defrost mode for a heat pump. That's new to me.

[BubbaHFD]

Are you sure that it is not stuck in defrost mode? If it is a heat pump when it goes into defrost the fan motor is supposed to shut off while the compressor runs. When it is this cold the heat pump does not work real well.

This most likely. Or bad news, the condenser fan motor could have had bad bearings and ceased. It's not a capacitor problem if the motor won't turn

[thegrouse]

I've never heard of defrost mode for a heat pump. That's new to me.

The heat pump is kind of line an air conditioner in reverse. It uses refrigerant to take heat from the outside air and transfer it inside. You can check it by putting the unit into air conditioning mode and setting the thermostat way down so it goes on to check the fan. Heat pumps can be tough to diagnose but you can check the fan this way. A competent tech should be able to figure it out.

[double bogey]

If it wont move with a stick, you need a new fan motor. And heat pumps must have a defrost cycle to clear the outdoor coil of frost, and ice. The system switches back to the cooling mode, and stops the outdoor fan, allowing the heat generated to defrost the coil. This generally only takes a couple of mins, and it brings the electric heat on to temper the indoor supply air, so you don't get cold air blowing.

The only thing I don't like about heat pumps, is getting out and working on them in this weather. But it beats a roof I guess, which is where I will be later this morning.

[double bogey]

A properly operating heat pump will work at temperatures below 0°. They will still produce more heat per watt of input than the electric backup heat. The problem is, that usually somewhere between 30° and 40°, the house needs more heat than the heat pump can produce, and it needs the auxiliary heat, usually electric strips.

[SabreKiller]

Are you sure that it is not stuck in defrost mode? If it is a heat pump when it goes into defrost the fan motor is supposed to shut off while the compressor runs. When it is this cold the heat pump does not work real well.

HVAC guy just left. Its the defrost mode control panel has gone out. Should be fixed pretty quick.

[thegrouse]

Good deal. Hopefully they have one in stock locally.

[John Bowy]

If the fan won't move freely it's not capacitor it is a bad motor

[John Bowy]

In temperatures below 40 degrees it's better to switch to emergency heat which runs your strips instead of the heat pump

[bowhntrmatt]

HVAC guy just left. Its the defrost mode control panel has gone out. Should be fixed pretty quick.

Glad you got it looked at professionally. I wasn’t sure if the term “froze” meant that the unit was a block of ice or that the fan motor just wouldn’t turn.

I’m amazed at the amount of wrong information given in responses to threads like this.

[bowhntrmatt]

In temperatures below 40 degrees it's better to switch to emergency heat which runs your strips instead of the heat pump

Why? Modern heat pumps work quite well until the temp goes below freezing for long periods of time. Heat strips are the most expensive way to heat a home.
Newer high efficiency models can even heat down into the negatives outdoor ambient without the use of electric strip backup.

[SFAbowhunter]

Why? Modern heat pumps work quite well until the temp goes below freezing for long periods of time. Heat strips are the most expensive way to heat a home.
Newer high efficiency models can even heat down into the negatives outdoor ambient without the use of electric strip backup.

^this. Do whatever it takes to not use the heat strips to heat your home. You'll have a big bill in no time if you do.