A humming outdoor unit with a fan that will not turn is the call we get most in July in New Bedford, MA, 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.
When the heat goes out, see Furnace Repair.
Warning Signs for AC Repair
The sooner you notice these red flags, the easier and cheaper the fix. Keep an eye out for the following clues:
- Warm or room-temperature air blowing when the thermostat calls for cooling
- Bubbling or hissing noises that point to a possible refrigerant leak
- Breaker trips or a burning odor at startup
- Ice on the refrigerant lines or a frozen indoor coil
- Rapid on-off cycling that never brings the temperature down
- Puddles near the air handler or water stains on the ceiling beneath it
- Higher summer bills even though the house still feels warm and humid
- A condenser fan that sits still while the outdoor unit hums
Early Action Saves Money
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 (774) 533-7670 for a fast inspection.
