An outside unit that hums while the fan stays still is the call we get most in July in Bismarck, ND, 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.
When to Call for AC Repair in Bismarck
Catching these issues early helps you avoid costly problems. Keep an eye out for the following clues:
- Breaker trips or a burning odor at startup
- Puddles near the air handler or water stains on the ceiling beneath it
- Vents blowing air that is barely cooler than the room
- An AC that turns on and off every few minutes but never cools down the house
- Cooling bills climbing while the house stays sticky and warm
- A hiss or gurgle from the lines, a common sign of leaking refrigerant
- Clicking or humming outside with no fan movement
- An iced-over evaporator coil or frozen refrigerant lines
Don't Wait for a Total Failure
Most HVAC failures start small, a weak capacitor, a squealing blower, a system that runs a little longer each week. At the first hint of a problem, call (701) 248-4402 for a fast inspection.
