Quick answer: When a coolroom is not cooling, work through this order: controller settings and display, condenser coil, condenser fan, evaporator ice and fan, probe position, then the controller and relay. These checks are safe and quick. If everything checks out, the cause is likely refrigerant or the compressor, and that needs a licensed refrigeration technician.
Coolroom not cooling: check these 7 things in order
| # | Check | What to look for |
|---|---|---|
| 1 | Controller and set point | Display on, set point correct, no alarm code |
| 2 | Condenser coil | Dust or grease blocking airflow |
| 3 | Condenser fan | Not turning, slow, stiff or noisy |
| 4 | Evaporator ice and fan | Frost on the coil, fan stopped |
| 5 | Probe position | Probe next to the evaporator or a door seal |
| 6 | Controller output and relay | Relay clicks but load does not run, burnt contacts |
| 7 | Refrigerant and compressor | Licensed technician only |
1. Controller and set point
Start at the display. Confirm the set point is what you expect and that no alarm is showing. A controller that has lost its settings or drifted can switch the compressor at the wrong times. If an alarm code is showing, use our guides for Dixell, Carel and Elitech controllers, or the fridge error codes guide.
2. Condenser coil
A condenser coil blocked with dust or grease cannot shed heat, so the unit runs for long periods and the room stays warm. Switch off, clean the coil with a soft brush and a vacuum, and leave space around the unit for airflow. In a busy kitchen, do this several times a year.
3. Condenser fan
The condenser fan must run whenever the compressor runs. With the power off, turn the blade by hand. A stiff blade, grinding noise or a fan that does not turn means the motor needs replacing. Do not leave the compressor running without it. See our full guide on a condenser fan motor not working.
4. Evaporator ice and fan
Look inside the room at the evaporator. Heavy frost blocks airflow and points to the defrost system. Test the defrost heater, timer and thermostat. A stopped evaporator fan gives the same result, so see evaporator fan not working.
5. Probe position and settings
Place the probe where it reads the cabinet air, not next to the evaporator or a door seal, or the readings will be misleading. Keep the probe lead away from hot components and sharp edges. Set the defrost interval and duration according to the manual for your equipment.
6. Controller output and relay
A controller's output relay is built for a limited current. If the compressor draws more than that rating, the contacts heat up, wear out and can weld or burn, and the controller fails. A backup relay takes over the heavy switching. If a relay clicks but the load does not run, or the contacts look burnt, replace it. If the controller has failed, replacing the sealed unit is usually faster than repairing it.
| Part | Details | Price (AUD) |
|---|---|---|
| Elitech EK-3030 coolroom controller | Low and medium temp, 71mm x 29mm cut-out, 10A or 16A output as listed | $45.00 |
| Backup relay 30A | 240V coil, 30A contacts, 6.3mm spade terminals | $17.00 |
| Controller mounting box | Pre-cut plastic body for Dixell, Carel and Elitech controllers | $17.50 |
| Condenser fan motor 5W | 240V, 1300/1550 RPM. 10W and 25W also available | $31.00 |
Check that the controller's cut-out, wiring and load suit your equipment before ordering. Replacement parts must match the original. Send us your current controller's model and a photo of its wiring if you are unsure.
7. Refrigerant and compressor
If the coil is clean, the fans run, the evaporator is clear and the controller and relay work, the fault may be low refrigerant or a compressor problem. That work needs a licensed refrigeration technician. We supply electrical and fan parts only and do not offer repairs.
Safety
Switch off and isolate the power before you touch any wiring. Controllers, relays and fan motors are mains-powered, so fitting should be done by a licensed refrigeration technician or electrician.
Browse all commercial fridge parts, coolroom controllers and condenser fan motors. Not sure which part fits? Use Find Your Part. Orders placed by 6pm Sydney time ship the same business day from Colebee, NSW.
Coolroom not cooling FAQs
Why is my coolroom not getting cold?
The most common causes are a blocked condenser coil, a failed condenser or evaporator fan, an iced evaporator from a defrost fault, a misplaced probe or wrong settings, and a failed controller or relay. Refrigerant or compressor faults need a licensed technician.
What should I check first on a coolroom that is not cooling?
Check the controller display and set point, then see whether the compressor and fans are running. Clean the condenser coil and look for ice on the evaporator. These checks are safe, quick and fix a large share of faults.
Where should the temperature probe go?
Place the probe where it reads the cabinet air, not next to the evaporator or a door seal. A probe in the wrong spot gives misleading readings and the controller will switch the compressor at the wrong times.
When do I need a backup relay?
Use a backup relay when your compressor draws more current than the controller's output relay is rated for. The controller then switches the relay coil and the relay carries the heavy load. Our relay is rated for 30A with a 240V coil.
Can a dirty condenser stop a coolroom cooling?
Yes. A condenser coil blocked with dust or grease cannot shed heat, so the unit runs for long periods and the room stays warm. Clean the coil with a soft brush and vacuum, and leave space around the unit for airflow.
Can I fix a refrigerant leak or compressor fault myself?
No. Refrigerant work and compressor repairs need a licensed refrigeration technician. We supply electrical and fan parts only. If the checks in this guide find nothing, call a licensed technician.