Why your fridge runs all the time, and when it is a problem

A fridge that never seems to switch off is one of the most common worries we hear about. Sometimes it is perfectly normal. Sometimes it is the first sign of a fault that will end with a failed compressor and an electricity bill that is higher than it should be. The trick is knowing which is which.

What counts as normal

A fridge is designed to run in cycles. In mild weather, a household fridge typically runs for roughly a third to half of the time. In Durban's summer, with a hot kitchen and the door opening often, it can run for much longer and still be healthy. Frost-free models also run extra during their defrost cycle. And a fridge that has just been loaded with warm shopping or just been switched on will run for hours to catch up.

What is not normal is a fridge that runs around the clock for days, is warm to the touch, is noisy, or still cannot hold a proper temperature.

The usual reasons a fridge runs too much

1. A dirty condenser coil

This is the number one cause. When the coil is covered in dust, the heat cannot escape, so the fridge works harder and longer to achieve the same cooling. Cleaning it a couple of times a year makes a real difference.

2. Poor ventilation

A fridge squeezed into a tight cupboard, pushed hard against the wall or sitting beside an oven or in direct sun has to fight its surroundings. Leave a gap of several centimetres at the back and sides, and keep it away from heat sources.

3. Worn door seals

If the rubber gasket is cracked, dirty or no longer sticks to the cabinet, warm air leaks in constantly. The fridge keeps trying to cool air that never stays cold. Try the paper test: if a sheet slides out easily, the seal is leaking.

4. The temperature is set too cold

A fridge set to its coldest setting will run almost non-stop and may freeze lettuce and milk. Around 3 to 5 degrees in the fridge and minus 18 in the freezer is the target. Colder wastes electricity and does not keep food any better.

5. The evaporator fan or defrost system has failed

If the evaporator fan stops, cold air does not circulate and the thermostat never gets the signal that the fridge is cold enough. A failed defrost system lets ice build up and block the airflow. In both cases the compressor keeps running while the cabinet stays warm.

6. The fridge is low on refrigerant or the compressor is weakening

If the gas has leaked out or the compressor is losing its efficiency, the fridge simply cannot remove heat quickly enough. It runs and runs and never quite gets there. This is the serious end of the list and needs a technician.

7. It is old

Older fridges lose efficiency as their insulation, seals and compressor age. A fridge that has run well for fifteen years can start running much longer without any single part being obviously faulty.

What it costs you

A fridge that runs far more than it should uses far more electricity, and in a country where tariffs keep climbing that adds up over a year. It also shortens the life of the compressor, because the part that wears out is the one that never gets to rest.

A quick check you can do

• Note how long the fridge runs and how long it rests over an hour or two.
• Feel the sides and the back. Warm is normal, hot is not.
• Listen for new noises, particularly from the freezer section.
• Put a thermometer in the middle of the fridge and read it after an hour. It should sit around 3 to 5 degrees.
• Check the door seals and clean the condenser coil.

When to call a technician

If you have cleaned the coil, checked the seals and set a sensible temperature, and the fridge still runs continuously or cannot hold temperature, book an inspection. A fault found early is almost always cheaper than one found after the compressor fails. We will tell you honestly whether the fridge is worth repairing, and we cover household fridges and commercial refrigeration across Durban.