Why is my upright freezer not holding the set temperature properly?

The most common causes in Irish hotel and banqueting kitchens are operational rather than “controller failure”:

Door discipline and gasket seal: frequent opening during service, damaged gaskets, or doors not fully closing will lift temperatures.

Airflow and loading: overfilling shelves, blocking the evaporator cover, or loading warm product too quickly will prevent recovery.

Condenser blockage: grease and dust on the condenser reduces cooling capacity and causes longer run times.

Ice build-up: icing around the evaporator/fan area restricts airflow and can create temperature swings.

Probe/location issues: a displaced or faulty temperature probe can make the controller “think” it is colder or warmer than it really is.

Immediate actions that protect stock: minimise door openings, move high-risk items to a back-up freezer if temperatures trend above safe limits, and record what you observed. If temperatures won’t recover after basic checks, use Unifrost Support to get the right troubleshooting route for your exact model and controller type.

Read the full guide: New Owner Quick Checks for Unifrost Upright Freezer Temperature Controllers.