Air conditioner tripping the breaker

Find out when it trips: instantly (short to ground), at compressor start (hard start, bad capacitor, weak breaker) or after running (overload, loose connection heating up). Never upsize a breaker beyond the nameplate maximum.

Single source ~60 min advancedBrands: All

Before you start

Turn off the breaker and the outdoor disconnect; confirm 0 V with a meter before touching wiring
Inverter and capacitor-start units hold dangerous voltage after power-off; wait the time on the label and verify 0 V DC before touching boards or capacitors
Repeated resetting onto a short is a fire risk

Diagnostic steps

Unlock all 6 steps with expected values

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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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