Straight to it
A Commercial Cool refrigerator that runs but does not cool is most often an airflow problem rather than a dead compressor: the evaporator ices over because defrost has stalled, air stops moving between the compartments, and the food warms while the machine works harder than ever. Two of the three usual causes are owner-checkable in minutes. What follows is arranged by likelihood rather than by how interesting each cause is.
What this looks like from the outside
- The condenser area underneath is packed with dust — Dust on the coil is the cheapest cause of poor cooling and the one most often overlooked.
- No sound of air moving inside the freezer with the door held closed — The evaporator fan is the only thing that moves air in there, and its silence is diagnostic.
- Ice cream soft but the milk still cold — The order in which compartments fail tells you which end of the air path is in trouble. Time it roughly, as the pattern matters more than the exact interval.
- NEAR MISS: nothing runs at all and nothing is cold — That is a starting fault rather than a cooling fault, and the page for a cabinet that will not start is the right one. It is the sort of check a technician does first, for the same reason.
Likely causes, ordered
- A stalled defrost cycle icing the evaporator — Ranked first because it is common, gradual and completely hidden until somebody takes the rear freezer panel off, which is why owners describe it as sudden. It earns this slot because it explains the whole symptom rather than part of it.
- A dust-blanketed condenser coil — Ranked here because it costs capacity rather than causing an outright failure: the system still works, just not well enough on a warm day or with a full cabinet.
- Blocked air vents inside the compartments — It belongs on the list because it is free to fix and because it is genuinely common after a big shop. This is the cause people skip, and skipping it is why the diagnosis takes three visits.
- A sealed-system or compressor fault — Last, and the only entry that is not owner work: a low charge, a restriction or a tired compressor all present as poor cooling, and none of them can be diagnosed without gauges.
The elimination order
- Hold the freezer door closed and listen for airflow — Silence inside the freezer while the compressor runs points straight at the evaporator fan or the ice around it. It takes less time than reading about it.
- Compare the two compartments honestly — Freezer hard and fridge warm means airflow. Both drifting warm together means the machine is losing capacity, not distribution.
- Run a sheet of paper around the door seals — A leak found here explains a warm cabinet on its own and costs nothing to confirm. Do this before the check below it, because the answer changes what that one means.
Steps you can do yourself
- Empty the freezer and let the cabinet defrost fully with the door open — A day with the power off clears the evaporator. Do not force anything; the plastic in a modern appliance breaks rather than bends.
Tools: towels, cooler boxAbout 30 min
- Move the cabinet clear of walls and cupboards — Air has to reach the condenser and leave again. A machine wedged into joinery is fighting for capacity before anything has failed. It is the sort of check a technician does first, for the same reason.
About 20 min
- Put a thermometer in each compartment and record it over a day — Readings from a thermometer are what tell you whether a change you made worked, and they are what a technician wants to hear. If it does not change anything, that result is still worth recording.
Tools: thermometerAbout 20 min
- Stop at this point: what follows needs a meter on a live circuit — What is left is diagnosis rather than inspection, and diagnosis needs instruments.
What to turn off before you start
Safety
Pull the plug before anything else; a wall switch is not proof the appliance is dead. The power being off is not the same as the machine being safe to touch immediately. Refrigerant work is licensed work: a line opened without the right recovery gear vents the charge and turns a repair into a replacement. Work with the door mechanism intact rather than around it.
When to call a technician
Stop and call when the picture changes: you own everything you can reach without a panel coming off inside the compartment; the rest needs gauges and a licence. Past that point, a wrong guess is expensive rather than merely annoying. Call without waiting if you can smell burning, see oil around the compressor, or hear the unit trying to start over and over.
Related pages of the same kind
How specific this page is
One page cannot be both general and exact, and this one is general by design.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
