Clothes dryer with its vent duct in a small laundry closet
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Field pattern: dryer thermal fuse blown? Find the airflow restriction before you replace it

A thermal fuse is a one-shot safety device; it opens because the dryer got too hot. Techs agree the usual root cause is restricted exhaust airflow (crushed transition hose, lint-packed duct, stuck exterior hood, lint in the blower), less often a cycling thermostat or a grounded element. The wrong turn is swapping the fuse and leaving: the new one blows again and the vent is a fire risk.

Cross-checked ~60 min moderateBrands: All

Before you start

  • Unplug the dryer (electric: both legs; gas: also turn off the gas shutoff before moving the unit)
  • Never bypass or jumper a thermal fuse to 'test run' a dryer
  • Lint around the burner or heater is a fire hazard: clean it before running the dryer

Diagnostic steps

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Field pattern: dryer thermal fuse blown? Find the airflow restriction before you replace it · OnCall Tech