Quick Answer
When the freezer is warm but the fridge still cools, the usual causes are a failed evaporator fan, a frosted-over defrost system, or blocked vents between the compartments. Check for heavy frost and listen for the fan before calling a local technician.
When your freezer is warm but the fridge still cools, the cause is usually a failed evaporator fan, a frosted-over defrost system, or blocked airflow vents between the two compartments. Because both sections often share one cooling system, a small fault can affect just one side.
Why one side fails while the other works
In most modern units, cold air is made in the freezer and shared with the fridge by a fan. If that fan or the defrost system fails, the freezer loses its edge first, even while the fridge limps along.
Cause 1: The evaporator fan
Open the freezer and listen. If you do not hear a soft fan running, the evaporator fan motor may have failed, which stops cold air from circulating.
Cause 2: The defrost system
Heavy frost on the back wall of the freezer suggests the defrost heater or thermostat has quit. The frost blocks airflow and the freezer slowly warms. This is closely related to the drain issues we cover in our post on why a refrigerator leaks water.
Protecting your food while you wait
Keep the doors closed as much as possible. FoodSafety.gov notes that a full freezer holds a safe temperature longer than an empty one, which buys you time.
Getting it fixed
The defrost system and fan are internal parts, so the safe next step is to get connected with a local Fairfield technician. Our freezer repair page explains the common parts involved.
Frequently asked questions
Should I unplug it and let it defrost?
A manual defrost can confirm a frost problem and temporarily restore cooling, but it will not fix a failed part.
How long can food stay safe?
A full freezer holds safe temperatures for roughly 48 hours if left closed; a half-full one, about 24.