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Outdoor AC Unit Humming but Fan Not Spinning
Outdoor condenser hums or clicks but the fan or compressor will not start. Often a capacitor or contactor issue. Safety and cost facts.
Safe things to check
- Turn the system off at the thermostat so it stops trying to start.
- Keep kids and pets away from the outdoor unit.
Stop here
Do not poke the fan, push it with a stick, or open the panel. The capacitor stores electric energy that can shock you, and Angi warns a failing capacitor can leak or burst. (Source: Angi)
What a technician checks
Angi explains that the AC capacitor stores energy to start the compressor and fan motors and often lasts 10 to 20 years; heat exposure can shorten its life. A contactor is the switch that powers the outdoor unit. A technician tests both before looking at the compressor. (Source: Angi; Angi)
Typical cost
Angi: capacitor replacement about $200 to $400 total, with many flat-rate jobs at $300 to $600; contactor replacement about $190 to $250, up to about $320. (Source: Angi; Angi) National figures; not a quote.
Refrigerate LLC in Lindon has HVAC-certified technicians and reviews every request. Prefer to talk? Call or text (801) 899-2171.
FAQ
Can I fix this myself?
Only the simple checks listed above. Gas, refrigerant and electrical work needs a trained HVAC technician.
Can this site tell me what is wrong with my furnace or AC?
No. Utah HVAC Help is general information, not a diagnosis. Gas, refrigerant and high-voltage electrical parts need a trained HVAC technician. If you smell gas or a CO alarm sounds, leave the building and call 911 and your gas company from outside.
Sources
- How Much Does AC Capacitor Replacement Cost? (2026 data, updated Aug 3, 2026), Angi
- How Much Does an AC Contactor Replacement Cost? (2026 data, updated Oct 13, 2026), Angi
Last checked October 27, 2026. Prices and rules change; confirm with the source before you rely on them.