Check the setpoint, independent readings and whether stock sits in the direct evaporator discharge.
In short: freezing in one location often means poor placement; freezing throughout may mean a sensor or control fault.
Do not calibrate by guesswork or alter service parameters. If cooling continues after the setpoint is reached, call a technician.
Symptoms
Temperature falls below setpoint, product freezes in a chiller, and ice forms on stock.
Causes and fixes
| Possible cause | How to check | Solution |
|---|---|---|
| Thermostat set too low | Read the controller display or dial. | Reset the setpoint to the correct value. |
| Faulty thermostat or sensor | Compare the controller reading against an independent thermometer. | Recalibrate or replace the sensor; call a technician if needed. |
| Product too close to evaporator | Stock sitting directly in the cold-air discharge freezes first. | Rearrange storage; keep a 100 mm minimum gap from the evaporator. |
| Stuck expansion valve | Evaporator runs extremely cold with an unusual frost pattern. | Requires a refrigeration technician — do not attempt to free it yourself. |
Why a chiller freezes
Chilled rooms run only a few degrees above 0 °C, so a sensor reading low by even 2–3 °C, or product parked in the discharge stream, is enough to drop pockets below freezing. Always verify the controller against a second, independent thermometer before assuming the refrigeration is at fault.
Related articles
- Cold room temperature problems: triage and overview
- Room not reaching target temperature
- Cold room temperature fluctuations
- Ice & condensation issues
- When to call a professional
- Daily operation
If the controller and an independent thermometer disagree, contact [email protected] for service options.
