A humming outdoor unit with a fan that will not turn is the call we get most in July in White Plains, NY, 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
Spotting the early warning signs lets you act before the problem gets expensive. Here are the most common indicators that it's time to call a professional:
- Clicking or humming outside with no fan movement
- A hiss or gurgle from the lines, a common sign of leaking refrigerant
- Frost or ice forming on the copper lines or the indoor coil
- Breaker trips or a burning odor at startup
- Room-temperature air from the registers even though the AC is running
- Puddles near the air handler or water stains on the ceiling beneath it
- An AC that turns on and off every few minutes but never cools down the house
- Rising electric costs paired with a sticky, uncomfortable house
Act Before It Gets Worse
A failing capacitor, clogged condensate drain, or dirty flame sensor rarely fixes itself and usually gets more expensive to address the longer it runs. Call (914) 436-5998 at the first sign of trouble.
