Short answer: A refrigerator that isn't cooling is most often set wrongly, packed too tightly against the wall, or suffering from a dirty condenser or a door that doesn't seal. If those are fine, the usual faults are a failed starting relay (the compressor clicks but won't run), a faulty thermostat or sensor, a stopped fan in frost-free fridges, or, less often than people assume, a refrigerant leak.
Five Checks Before You Call Anyone
Setting: put the dial or display at the middle setting and wait four hours.
Space: pull the fridge 10 cm from the wall; it needs room to release heat.
Door seal: close a sheet of paper in the door. If it slides out freely, the gasket is leaking.
Vents: inside, make sure food isn't blocking the air vents, especially at the back.
Listen: is the compressor at the back running, silent, or clicking every few minutes?
What the Sound Tells You
Silent: thermostat, control board or power to the compressor
Clicking every few minutes: starting relay or overload, an inexpensive fix
Running constantly but not cooling: dirty condenser, a weak gasket, or low gas from a leak
Freezer cold, fridge warm: a fan or defrost fault. Read this guide
Does a fridge need gas every few years?
No. Low gas means a leak, which must be repaired before recharging. Our approach to gas charging
How long will food last while I wait?
About four hours in a closed fridge, longer in a full freezer. Keep the doors shut.
