Why Is My Commercial Fridge or Freezer Not Cooling?

First, the safe checks you can do yourself

Before calling for help, a few quick checks resolve a surprising number of 'not cooling' call-outs. None of these involve opening the sealed refrigeration system.

If the unit is completely dead, start with the power supply. If it is running but warm, the most common causes are a dirty condenser, a poor door seal, or blocked airflow.

• ✓ Confirm the unit has power and the plug/isolator is on
• ✓ Check the temperature setpoint hasn't been changed
• ✓ Make sure doors close fully and seals are intact
• ✓ Check nothing is blocking internal airflow or the door
• ✓ Look for a thick layer of dust on the condenser coil
• ✓ Confirm the unit isn't overloaded with warm stock

A dirty condenser coil — the most common cause

The condenser rejects heat from the system. In a busy kitchen or shop it clogs with dust and grease, which traps heat and stops the unit reaching temperature — especially on hot days. Cleaning the condenser coil (with the unit isolated) is routine maintenance and resolves many warm-running complaints.

If cleaning the condenser and giving it clear airflow does not restore cooling within a few hours, the problem is likely deeper.

Door seals, airflow and overloading

Worn or dirty door gaskets let warm air leak in continuously, so the unit can never catch up. Overloading — or stacking product against the internal vents — blocks the cold air from circulating. Putting large quantities of warm stock in at once also overwhelms the system temporarily.

These are operational issues rather than faults, but they produce the same symptom: a unit that won't hold temperature.

Icing and defrost problems

A heavy build-up of ice on the evaporator coil indicates a defrost fault. Ice insulates the coil and chokes airflow, so the cabinet warms even though the compressor is running. Causes include a failed defrost heater, a faulty defrost timer or controller, or a door left ajar letting in humid air.

Switching the unit off to let it fully defrost may restore cooling temporarily, but if ice returns the underlying defrost fault needs a technician.

Refrigerant and compressor faults — call a technician

If the basics are ruled out, the cause is usually inside the sealed system: a refrigerant leak, a failing compressor, or an electrical/control fault. These require a qualified refrigeration technician with the right equipment — refrigerant must never be vented, and a leak must be found and repaired, not simply topped up.

Because spoiled stock is expensive, it is worth moving product to a working unit and calling for a repair as soon as the simple checks are exhausted.