A humming outdoor unit with a fan that will not turn is the call we get most in July in Waterloo, IA, and the cause is usually a failed run capacitor. That inexpensive component starts the compressor and fan, fades for years without complaint, and then quits under peak load. It is far from the only suspect, though. Contactors pit and stop passing clean power, condenser fan bearings dry out, small refrigerant leaks drain away cooling capacity, and evaporator coils ice over when a clogged filter strangles airflow.
For winter breakdowns, see Furnace Repair.
Warning Signs for AC Repair
Spotting the early warning signs lets you act before the problem gets expensive. Keep an eye out for the following clues:
- Room-temperature air from the registers even though the AC is running
- The system short-cycling every few minutes without cooling the house
- A burning smell or repeated breaker trips when the AC starts
- The outdoor unit humming or clicking but the fan not spinning
- Puddles near the air handler or water stains on the ceiling beneath it
- Frost or ice forming on the copper lines or the indoor coil
- Rising electric costs paired with a sticky, uncomfortable house
- Hissing or bubbling sounds that suggest a refrigerant leak
Don't Wait for a Total Failure
A failing capacitor, clogged condensate drain, or dirty flame sensor rarely fixes itself and usually gets more expensive to address the longer it runs. At the first hint of a problem, call (319) 422-7030 for a fast inspection.
