Whirlpool Refrigerator: not defrosting

Professional Repair Guide

What is this symptom?

Is your Whirlpool refrigerator not defrosting? This issue is often indicated by frost buildup in the freezer compartment and on evaporator coils, leading to cooling performance problems. The automatic defrost cycle may not be functioning correctly, which can result in excessive ice accumulation and hinder the overall efficiency of your appliance.

Urgency: Medium

Important Tips for Whirlpool Models

Whirlpool models often use a defrost timer or control board to switch into defrost cycles; checking timer advancement manually is a recognized troubleshooting step.

Possible Causes

Faulty defrost timer

How to Identify: Freezer ice buildup; manually advancing timer should initiate defrost cycle; if compressor does not shut off and heater does not activate when advanced, timer is likely defective

Part: Defrost timer

Defective defrost thermostat

How to Identify: Evaporator coils remain iced; thermostat fails multimeter continuity test at low temperatures indicating failure to close contacts to energize defrost heater

Part: Defrost thermostat

Defrost heater failure

How to Identify: Frost persists despite defrost cycle; multimeter shows no continuity on heater; no heat generated during defrost attempt

Part: Defrost heater assembly

Thermistor or defrost sensor fault

How to Identify: Temperature sensor fails to signal defrost control; multimeter test or diagnostic resistance anomalies; some models share thermistor for defrost control.

Part: Thermistor/defrost sensor

Defrost control board failure

How to Identify: All defrost components test good but fridge still wonâ€™t enter defrost; control board not delivering voltage to defrost components

Part: Defrost control board/main control board

Door gasket/air leak causing excess frost

How to Identify: Poor seal, visible gasket damage, excess frost near door edges, unusually frequent frost buildup

Part: Door gasket

DIY Solutions

Test and Replace Defrost Timer

Moderate 30â€“60 minutes

Tools Needed: screwdriver, multimeter

Unplug fridge and locate defrost timer (control panel or rear bottom).
Use multimeter to check continuity and manually advance into defrost; if no defrost cycle, replace timer.
Install new timer wiring in correct orientation and reassemble panels.
Plug in fridge and monitor for restored automatic defrosting.

⚠️ Safety First: Unplug appliance before accessing electrical components.

Test and Replace Defrost Thermostat

Moderate 30â€“60 minutes

Tools Needed: screwdriver, multimeter

Unplug fridge and access back panel inside freezer to reach defrost thermostat near evaporator coils.
Remove thermostat lead and test for continuity at low temperatures with multimeter.
Replace defective thermostat with modelâ€‘specific part and reconnect wiring.
Restore panels and plug in fridge, verify frost reduction over next defrost cycle.

⚠️ Safety First: Ensure power is disconnected and be cautious around sharp sheet metal.

Test and Replace Defrost Heater

Advanced 1â€“2 hours

Tools Needed: screwdriver, nut driver, multimeter

Unplug fridge and remove freezer back panel to expose evaporator coils and heater.
Disconnect heater and test for continuity; if open circuit, replace heater assembly.
Reinstall evaporator cover and panels, reconnect power, and monitor defrost function.
Allow fridge to run several cycles to confirm issue is resolved.

⚠️ Safety First: Ensure power is off; coils are fragile; handle with care.

Professional Repairs

Control Board Diagnostics and Replacement

Estimated Cost: $150 - $400

Blocked Defrost Drain or Drain Heater Repair

Estimated Cost: $100 - $250

When to Call a Professional

If testing or replacing defrost components is beyond your comfort or skills

If refrigerator under warranty to avoid voiding warranty

When control board or integrated electronics faults are suspected

Preventive Maintenance

Check and clean door gaskets regularly: Excess air ingress and frost buildup
Frequency: monthly
Inspect evaporator drain and clear blockages: Ice buildup in defrost drain leading to water pooling
Frequency: annually

Frequently Asked Questions

Why is my Whirlpool Refrigerator not defrosting?

Common causes include a faulty defrost timer, defective thermostat, or heater failure.

How do I fix Whirlpool Refrigerator not defrosting myself?

You can test and replace the defrost timer, thermostat, or heater with moderate to advanced DIY skills.

How much does it cost to fix not defrosting?

Professional repairs can range from $100 to $400, depending on the issue and parts needed.

When should I call a technician for not defrosting?

Consider calling a technician if the problem persists after DIY attempts or if you're unsure about the repairs.

Community Analytical Insights

Analysis based on real user discussions from appliance repair communities

Can I Fix This Myself?

40%

DIY Success Rate Difficulty: DIY

Common Issues Reported by Users

Defrost thermostat failure (3 mentions)
Control board malfunction (2 mentions)

User Suggested Solutions

Check and replace the control board or wire harness for continuity issues.

Success rate: 17.0%
Reconnect loose wire connections on the heater core.

Success rate: 17.0%

Analysis based on 5 community discussions
View Sources

Data compiled from real discussions on r/appliancerepair and r/Appliances:

Community Discussions

freezer over freezes and causes refrigerator to become warm

Loose wire connection on the heater core was the issue, which was resolved by plugging it back in.

DIY View on Reddit →

icing up, defrost system issue

Replace the control board or check the wire harness for continuity issues.