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Whirlpool Refrigerator dF — Defrost System Failure

Whirlpool Refrigerator · Error code dF

What dF Means

The control board did not see the evaporator temperature rise during a defrost cycle, meaning the defrost heater, defrost thermostat, or bimetal sensor is not working. Frost will keep building on the coil until airflow is choked and the fridge stops cooling.

Symptoms

  • 'dF' on display
  • Heavy frost on freezer back panel
  • Fresh food warming up while freezer stays cold
  • Fan noise from blocked evaporator

Common Causes

1
Failed defrost heater

Heater coil has gone open and is not melting frost.

2
Failed defrost thermostat / bimetal

Bimetal stuck open and never closes to power the heater.

3
Damaged defrost element wiring

Burned wire or terminal at the heater.

4
Failed main control board

Defrost relay on the board failed.

How to Fix It

  1. Manually defrost the fridge — unplug, empty the freezer, leave doors open 8+ hours with towels on the floor.
  2. Once thawed, remove the freezer back panel to expose the evaporator coil.
  3. Test the defrost heater for continuity (should read a few dozen ohms).
  4. Test the bimetal/defrost thermostat by chilling it in ice water and ohming — should close cold.
  5. Replace the failed component. If both test good, replace the main control board.

Parts You May Need

If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.

Common replacement Defrost heater View on Amazon→ Common replacement Defrost bimetal thermostat View on Amazon→

More Whirlpool Refrigerator Codes

6 (flashing) Flashing 6 — 6th Sense Active CE CE — Communication error between control boards CF CF — Communication Failure Co Co — Cooling Off / Demo Mode Er Er — Generic Error / Control Glitch F3 E1 F3 E1 — Fresh Food Thermistor Fault

All Whirlpool codes → All refrigerator codes →

Verified against manufacturer documentation: ifixit.com

Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician.