An outside unit that hums while the fan stays still is the classic summer service call in Kirkland, WA, 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
Catching these issues early helps you avoid costly problems. Here are the most common indicators that it's time to call a professional:
- Hissing or bubbling sounds that suggest a refrigerant leak
- Frost or ice forming on the copper lines or the indoor coil
- Cooling bills climbing while the house stays sticky and warm
- The system short-cycling every few minutes without cooling the house
- A condenser fan that sits still while the outdoor unit hums
- Breaker trips or a burning odor at startup
- Warm or room-temperature air blowing when the thermostat calls for cooling
- Water leaking around the indoor unit or from the ceiling below it
Early Action Saves Money
Left unchecked, even a small fault or temperature swing often signals a system working its way toward a breakdown. If you notice any of these signs, call (425) 969-3519 for a prompt inspection.
