Outdoor condensing unit with a large fan on a steel stand
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Central AC shut off by the condensate float switch

Float switches cut the cooling circuit when condensate backs up, usually from an algae or dust clog in the drain line or a failed condensate pump. Clear the drain, let the switch dry/reset, and find out why it backed up. Never bypass the switch.

Cross-checked ~45 min easyBrands: All

Before you start

  • Turn off power to the air handler/furnace before working at the pan or switch.
  • Do not jumper or bypass the float switch.

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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Central AC shut off by the condensate float switch · OnCall Tech