Main electrical panel beside a subpanel with its cover removed

Replace the defrost heater and defrost thermostat (top-freezer refrigerator)

In a top-freezer the evaporator is behind the freezer back wall, with the defrost heater along its bottom and the bi-metal defrost thermostat clipped to the coil tubing. Melt the frost first, test, then replace the failed part (or both, since they share the same access). On many units the heater is held by aluminum straps and slides down out of the coil; the thermostat may be plug-in or need splicing with sealed connectors.

Cross-checked ~90 min moderateBrands: All

Before you start

Unplug the refrigerator before removing the evaporator cover.
Melt frost with warm air or towels; never chip ice with a knife or screwdriver: a punctured evaporator is a sealed-system repair (blocked, refer to an EPA 608-certified technician).
Keep a heat gun or hair dryer moving and away from plastic liner parts.
Evaporator fins are sharp: wear gloves.

Diagnostic steps

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