When a fridge stops cooling, many people assume the compressor has died and start shopping for a new fridge. In our Kariega repairs, the compressor is often not the problem at all. Here is how to tell the difference and what your options are.

Quick answer

True compressor failure shows as a fridge that is completely warm with the compressor silent, humming without starting, or very hot and cutting out. But a failed starter relay, overload, capacitor, fan, thermostat or defrost system can look similar and costs far less to fix. A technician should test these first. Compressor replacement is often worthwhile on newer or premium fridges, less so on old, small ones.

What the compressor does

The compressor is the pump at the heart of the fridge, usually a black dome-shaped unit at the bottom back. It compresses refrigerant gas and pushes it around the sealed system. Without it, there is no cooling. It is also the most expensive part to replace, which is why it is worth being sure before condemning it.

In Kariega's hot summers, compressors work harder and run longer, so they do fail more often than at the coast. But the parts around the compressor fail even more often.

Signs that could point to the compressor

  • The fridge and freezer are both warm
  • You cannot hear the compressor running at all
  • The compressor hums but does not start, then clicks off
  • The compressor is extremely hot and cuts out after a short time
  • The fridge trips the power when the compressor tries to start
  • Loud knocking or rattling from the compressor

The lookalikes

Many of these signs can come from cheaper components. Here is what a technician checks before blaming the compressor.

Starter relay and overload

These small parts sit on the side of the compressor and help it start. When they fail, the compressor clicks and does not start, or does not try at all. They are inexpensive and quick to replace. This is the single most common fault mistaken for a dead compressor.

Start or run capacitor

Some compressors use a capacitor to start. A failed capacitor causes humming without starting.

Condenser fan

On fridges with a fan near the compressor, a failed fan means the compressor overheats and cuts out. It looks like a failing compressor, but the fix is a fan motor.

Thermostat or temperature sensor

If the thermostat never calls for cooling, the compressor never runs. The fridge seems dead, but the compressor is fine.

Control board

On electronic fridges, the board switches the compressor on. A failed board, often after a surge, can leave a healthy compressor sitting idle.

Defrost system

In frost-free fridges, a failed defrost heater or timer lets ice block the airflow. The compressor runs fine, but the fridge gets warm. This is very common.

Evaporator fan

The fan inside the freezer section blows cold air around. If it fails, the compressor runs but cold air does not circulate.

When it really is the compressor

If testing shows the compressor itself has failed, either electrically (open or shorted windings) or mechanically (seized or no longer pumping), replacing it is a significant job. It involves cutting it out of the sealed system, fitting a new compressor and filter drier, vacuuming and recharging with refrigerant.

When replacement is worth it

  • The fridge is less than about eight to ten years old
  • It is a larger, premium or built-in model that would be expensive to replace
  • The rest of the fridge, including the cabinet, seals and liner, is in good condition

When a new fridge may make more sense

  • The fridge is old, small or budget
  • The cabinet is rusted, the liner cracked or there are other faults
  • The repair cost is close to the price of an equivalent new fridge
  • You also want better energy efficiency

We give you the numbers and our honest view, and you decide.

Protecting the compressor

  • Keep the condenser clean so the compressor runs cooler.
  • Ventilate. Leave space around the fridge, and avoid placing it next to the stove or in direct sun.
  • Use a delayed-restart surge protector to prevent hard restarts after power cuts.
  • Do not overload or block vents inside, so air circulates properly.
  • Switch off if it clicks repeatedly. Repeated failed starts overheat the compressor.

Getting a diagnosis in Kariega

We test the relay, overload, capacitor, fans, thermostat, defrost system and board before reaching any conclusion about the compressor. In Kariega and Despatch, most callouts are same day or next day. Send us a photo of the rating plate and describe what you hear, and we can often bring the parts most likely to be needed.

Frequently asked questions

My fridge clicks every few minutes. Is the compressor dead?

Not necessarily. Most often it is a failed starter relay or overload, which is an inexpensive repair. Switch the fridge off and have it tested.

How long do fridge compressors last?

Many last the life of the fridge. Heat, dirty condensers, power surges and constant running shorten that life.

Can a compressor be replaced on any fridge?

Technically, on most fridges, yes. Whether it is economical depends on the fridge's age, size, quality and condition.

Apex HVAC is an independent company and is not affiliated with or authorised by any appliance manufacturer. This guide is general advice. For anything involving electricity or refrigerant gas, use a qualified technician.

Need a hand? See our fridge and freezer repair service in Uitenhage (Kariega).