Why does my fridge make gurgling, clicking and humming noises?
Most fridge noises are the normal sounds of a refrigeration cycle doing its job — and knowing which sound comes from which component tells you immediately whether to worry.
The normal noises and their causes:
Gurgling or bubbling. Refrigerant moving between liquid and gas phases as it circulates. Most noticeable shortly after the compressor stops, when pressures are equalising. Entirely normal and arguably the most reassuring sound a fridge makes.
Humming or a low drone. The compressor running. Modern fridges run it far more of the time than older ones, at lower speed, which is more efficient — so "it seems to be on constantly" is frequently normal rather than a fault.
Clicking. Usually the thermostat or relay switching the compressor on or off. A click followed by silence, repeating every few minutes, is different — see below.
Cracking or popping. Thermal expansion and contraction of plastic liners and shelving as temperatures change. Common during defrost cycles.
Hissing or sizzling during a defrost cycle, as water drips onto the warm evaporator heater.
Whirring — the evaporator or condenser fan, in frost-free models.
The noises that indicate a problem:
Rapid clicking every few minutes with no hum following. The compressor is attempting to start and failing — typically a failed start relay or capacitor, or a seized compressor. This one needs attention.
Loud rattling that changes if you touch the appliance — usually something resting against the back, a loose drip tray, or the fridge in contact with a cabinet.
Grinding or screeching — a failing fan motor, sometimes a fan blade fouled by ice buildup.
A sudden change in the usual noise pattern is more informative than any particular sound.
What genuinely reduces noise: levelling the appliance, leaving clearance at the back and sides for airflow, checking the drip tray is seated, and keeping the condenser coils clean.