LG Freezer Not Freezing — Fix Guide

What Does This Error Mean?

If your LG freezer is not freezing, check for ER DH (defrost heater fault) or ER FF (evaporator fan fault) on the display. These are the two most common causes of an LG freezer losing its chill.

How to Fix It

Check the display panel for error codes — ER DH means the defrost heater has failed, ER FF means the evaporator fan has failed. Both prevent the freezer from reaching -18 degrees C.
Open the freezer and press the rear panel. If you feel a solid wall of ice behind it, a defrost failure has been occurring for some time and the evaporator coils are blocked with ice.
Manually defrost the unit by unplugging and leaving the doors open for 24-48 hours. Place towels on the floor to absorb the meltwater.
After defrosting, remove the rear panel and test the defrost heater (ER DH), thermal fuse, and defrost thermostat with a multimeter. Replace any component that shows no continuity.
If no error code appears and the evaporator is clear of ice, check the start relay on the compressor. Shake it — a rattle means it needs replacing. A new relay often costs under £10.

Frequently Asked Questions

My LG freezer has frost on the back wall — is that normal?

A thin even layer of frost is normal. Heavy frost build-up (more than 5-6 mm thick) indicates a defrost failure. The frost insulates the evaporator coils and the freezer gradually warms up.

LG freezer not freezing but fridge section is fine — what does that mean?

If the fridge is cold but the freezer is not, the freezer evaporator coils are likely blocked with ice (defrost failure). Cold air is generated there but cannot pass through the ice layer.

How much does an LG defrost heater replacement cost?

Typically £15-£40 for the part. A full defrost kit (heater, thermal fuse, and thermostat) is usually under £60 and is a straightforward DIY repair.