An anti-freeze alarm on your chiller is a serious warning and not a minor inconvenience. It means that the system has detected fluid temperatures approaching freezing conditions, which could lead to ice forming inside the evaporator. If ignored, this can result in severe and costly damage to the unit.
Understanding what causes the alarm and what steps to take when it’s triggered is highly advisable for anyone working with water or glycol-based chillers.
What Is an Anti-Freeze Alarm?
Anti-freeze alarms are built-in safety functions designed to prevent ice formation within the chiller system, especially around the evaporator coil. They’re a feature of well-designed chiller systems. If water freezes inside these components, it expands and causes cracking, ruptures or total failure.
These alarms are typically triggered by:
- Water or glycol mixture approaching a preset low temperature threshold, typically 0℃
- Sensor readings falling outside of the safe operating range
- Excessively low ambient temperatures affecting exposed pipework
- A failing pump, blocked strainer or airlock reducing flow, allowing fluid to drop below safe temperatures.
In such situations, the alarm acts as a failsafe, stopping the unit from causing permanent damage.
What Should You Do When an Alarm Triggers?
Do not attempt to restart the chiller immediately. Instead, you should acknowledge the alarm without clearing it because the system has shut down to protect itself and should remain in its current, alarmed state. Check fluid temperature readings. You can often verify them via a display panel or by using an external thermometer. In addition, check the flow rate and pump operation to ensure there are no obstructions or airlocks. If the fault cannot be safely identified and resolved, isolate the unit and seek professional assistance.
What Happens If the Alarm Is Ignored?
Resetting or ignoring an anti-freeze alarm without resolving the cause can lead to:
- Ice formation in the evaporator, which may cause physical damage,
- Cracked pipework or fittings, especially in colder environments,
- System-wide shutdown or cascading faults,
- Increased risk of downtime and emergency repair costs.
In the end, what starts as a temperature warning can quickly develop into a full system failure, so ignoring the situation would be a mistake.
When to Call for Help
If you are unable to confirm safe operating conditions or if the alarm continues to trigger after an initial reset, it is important to stop using the chiller immediately. Continued operation under fault conditions can cause lasting damage to the system. At this point, the best course of action is to log the alarm event, including temperature data and any unusual readings, and contact us so these readings can be reviewed by a properly qualified person.
An Evolution Cooling technician will be able to verify sensor calibration, assess the glycol concentration and confirm that all flow and temperature conditions are within safe limits for you. Only once the system has been properly diagnosed and recommissioned by one of our professionals should it be returned to normal operation. We offer 24/7 emergency callouts as well as expert chiller maintenance plans.
