Outdoor fan or indoor fan runs but compressor doesn't (capacitor & contactor)

On central AC and many room units, a weak run/start capacitor or burned contactor is the usual cause. Test the capacitor µF against its label and the contactor coil and contacts. A compressor that still won't run with good parts is sealed-system territory.

Cross-checked ~45 min advancedBrands: All

Before you start

240 V is present at the condenser and contactor: kill the disconnect and verify zero volts.
Discharge the capacitor before handling (short C to HERM and C to FAN through a resistor or insulated tool).
Photograph wiring before removing the capacitor.

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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