What does it mean when a freezer is not freezing?
It means the freezer cannot reach or hold about -18 °C. A freezer that is cold but not freezing is still working, but weakly. A freezer that is warm and silent has no power or a compressor that is not starting.
Common causes of a freezer not freezing
The most common causes are a poor door seal, frost build-up and poor ventilation.
At a glance
| Cause | Typical sign | Who fixes it |
|---|---|---|
| Wrong setting or overload | Soft food after a big load | You can check this |
| Freezer not sealing | Frost around the door edge | You can check this |
| Frost build-up | Thick ice on the walls | You can check this |
| Dirty or unventilated condenser | Compressor runs constantly | You can check this |
| Failed fan or defrost system | No fan sound, frosted back panel | Technician |
| Failed start relay, thermostat or board | Clicking or a silent compressor | Technician |
| Refrigerant leak or worn compressor | Runs constantly, cool not frozen | Technician |
- 1
The setting is wrong or the freezer is overloaded
You can check thisThe control sets the target temperature, and a dial is easily bumped. A large load of warm food also raises the temperature for hours. The sign is soft food after a big shop.
- 2
The freezer is not sealing when closed
You can check thisThe door or lid seal keeps warm, damp air out. A dirty, flattened or torn seal, a drawer that sticks out or ice on the door frame stops it sealing. The sign is frost around the door edge. Clean the seal, and have a torn one replaced.
- 3
Frost has built up
You can check thisA manual-defrost freezer collects frost on its walls and shelves. Thick frost insulates the cooling surfaces. The sign is ice more than a few millimetres thick, and the fix is a full defrost.
- 4
The condenser is dirty or has no ventilation
You can check thisThe condenser releases the heat taken out of the freezer. Dusty coils, or a cabinet pushed against a wall, trap that heat. The sign is a compressor that runs constantly.
- 5
The evaporator fan or defrost system has failed
TechnicianA frost-free freezer uses a fan to move air over the evaporator and a heater to defrost it. The signs are no fan sound, or thick frost on the back panel. In a fridge freezer this shows first as a fridge not cooling while the freezer works.
- 6
The start relay, thermostat or control board has failed
TechnicianThe thermostat or control board tells the compressor to run, and the start relay starts it. A click every few minutes points to the relay. Silence points to the thermostat or board. A technician tests each part.
- 7
The refrigerant has leaked or the compressor is worn
TechnicianThe signs of a refrigerant leak or a worn compressor are constant running and a freezer that stays cool but not frozen. This is sealed-system freezer repair for a technician only.
What you can safely check yourself
You can check all of this without opening any panel. Switch off and unplug at the wall before touching anything at the back.
- Check the power and the settingConfirm the plug point works. Set the dial to the middle, or the display to -18 °C.
- Measure the temperaturePlace a freezer thermometer between frozen packs. Read it after 8 hours with the door closed.
- Test the sealClose the door or lid on a strip of paper. It should grip all the way around.
- Defrost if frostedSwitch off, unplug and let all the ice melt. Never chip ice with a knife.
- Clean and ventilateBrush dust off the coils at the back. Leave open space around the back and sides.
When to stop and call a technician
Stop and call a technician if the compressor clicks on and off, runs constantly without freezing or is silent with the light on. Stop if you smell burning, if the freezer trips the power or if water is near the plug or wiring. Stop if the fault returns after a full defrost. Do not open the compressor terminal cover, the control board or the sealed refrigeration system.
Still having trouble with your freezer?
Our technician comes to your home, usually the same day. The R450 call-out falls away if you go ahead, and you get a fixed price in writing before any work starts.
How a technician diagnoses a freezer that is not freezing
- Measures temperature and run timeThe technician measures the temperature and notes whether the compressor runs, cycles or stays off.
- Tests the start componentsThe start relay, overload protector and compressor windings are tested with a meter.
- Checks the controlsThe thermostat, sensor and control board are tested for correct switching.
- Inspects the evaporatorFull ice points to a defrost fault. Frost on only part of the evaporator points to a refrigerant fault.
Why is my chest freezer not freezing?
A chest freezer most often stops freezing because of frost build-up, a lid that does not seal or a bumped thermostat dial. Check that food is not holding the lid up, and defrost it if the walls are iced. On most chest freezers the condenser is inside the outer walls, so leave space around the sides.
Is a freezer that is not freezing worth repairing?
Repair usually makes sense when
- The fault is a seal, fan, thermostat, start relay or defrost part
- The compressor runs and the cabinet is sound
- The freezer is otherwise in good condition
Replacement is worth considering when
- The refrigerant leak is inside the foamed cabinet wall
- The compressor has failed on an old freezer
- The cabinet or lid is rusted through