Heat Pump Outdoor Fan Not Spinning?
In winter, a stopped fan is sometimes the heat pump doing its job. Sometimes it's a part the size of a soda can. Here's how to tell which before you call.
Quick Answer
If the fan stopped, the unit is steaming, and it starts again within about ten minutes, that's a normal defrost cycle and nothing is wrong. If the fan stays stopped while the compressor hums, the usual suspects in order are a failed fan capacitor, a fan motor that has seized or burned out, or a defrost control board stuck in defrost. If nothing outside runs at all, start with the breaker and the outdoor disconnect.
Do not reach into the top of the unit to push the blades, even with the power off. Capacitors hold a charge, and a stalled motor can start without warning.
Is It Defrost, or Is It Broken?
Defrost looks alarming and is completely normal
Below about 40 degrees, frost builds on the outdoor coil. Every so often the heat pump reverses itself for a few minutes to melt it: the outdoor fan stops, the coil steams like a kettle, you may hear a whoosh, and the air inside goes lukewarm because the auxiliary heat strips carry the house. Then the fan spins back up and it all goes back to normal. Ten minutes, tops. Arkansas winters, with damp nights in the 30s, trigger defrost more than people expect.
Stopped for more than 15 minutes with the compressor humming: capacitor or motor
The fan capacitor gives the motor its starting kick and helps it run. When it weakens, the fan hums or twitches and never comes up to speed, or it spins slowly and stops. A seized fan motor won't move at all, and you may have heard it grinding or squealing for a few weeks first. Either way, the compressor keeps running without the fan to move air across the coil, which is hard on it. Turn the system to emergency heat and call. Both are one-visit repairs; the capacitor is one of the cheapest fixes we do.
Stopped, coil solid with ice, never melts: defrost control
If the unit is encased in ice and the fan never restarts, the defrost board or its sensor may be stuck, or the unit may be stuck in defrost with the fan legitimately off. A low refrigerant charge causes the same picture. This is a technician diagnosis with gauges and a meter, and it is exactly what our heat pump frozen over page walks through.
Nothing outside runs at all: power first
Check the breaker for the outdoor unit (often a separate 30 to 60 amp breaker) and the disconnect box on the wall beside the unit. A tripped breaker that trips again after one reset is telling you the motor or compressor is drawing too much current. Leave it off and call.
What's Safe to Do Yourself
Wait ten minutes and watch
Set a timer. If the fan restarts on its own and the steam clears, you just watched a defrost cycle. If it does not, keep reading.
Listen at the unit
A steady hum with no fan movement points at the capacitor. A click and then nothing points at the contactor or the board. Grinding or a squeal that stopped recently points at the motor. Tell us what you heard and the truck rolls with the right part.
Check the breaker and disconnect once
Reset a tripped breaker one time. If it trips again, stop. Do not keep resetting it; that is how a bad motor takes the compressor with it.
Switch to emergency heat and call
On the thermostat, select emergency heat (sometimes labeled EM or AUX). The house stays warm on the electric strips while you wait. It costs more per hour to run, so it is a bridge, not a fix.
Related winter heat pump problems
Unit iced over and not melting: heat pump frozen over. Auxiliary heat running nonstop and the bill climbing: aux heat won't turn off. Indoor blower humming but not spinning: blower hums but won't spin. No heat from anything: no heat checklist. Same fan symptom in July is the same capacitor; the fix does not change with the season.
Ready for a pro to take it from here?
Fan capacitors and outdoor fan motors for every major brand ride on our winter trucks, so most stopped-fan calls are fixed in a single visit. Our heat pump repair crews run same-day calls across Central Arkansas — including heating repair in Bryant, heating repair in Benton, heating repair in Little Rock, North Little Rock, Conway, Sherwood and Maumelle. Night, weekend, or holiday? 24 hour heating repair is a real person on the line, not a recording.
Fan Still Stopped After Ten Minutes? Switch to Emergency Heat and Call.
$149 flat diagnostic, $75 credited to the repair, and same-day heat pump repair across Little Rock, Bryant, Benton, Conway, and Central Arkansas.
Call 501-307-5959