Refrigerant is at the heart of any industrial cooling unit’s operation. However, leaks constitute an environmental concern, particularly with HFCs, and must be dealt with promptly under UK F-Gas regulations. Learn how to spot the warning signs of a leak, what causes them and what to expect during the repair process.
What Causes Refrigerant Leaks in Chiller Units?
Refrigerant leaks often develop gradually, but they can occur in any part of the system where pressure and mechanical stress are present. Common causes include:
- Corrosion on copper pipework or joints, often due to moisture ingress.
- Worn valve seals or deteriorating O-rings around access ports.
- Excessive vibration from compressors, loose mounts or poorly insulated lines.
- Improper installation or mechanical damage from previous servicing.
Older systems are especially prone to leaks, as component fatigue and material wear build up over time. On the other hand, well-designed chiller systems can go without leaks for years.
How to Spot a Refrigerant Leak Early
Identifying a refrigerant leak early can prevent more serious damage and reduce operational disruption. For example, you may notice a sudden drop in chiller performance, such as reduced cooling capacity under normal load conditions. Another common indicator is a rise in energy bills despite no change in operating hours or ambient temperatures.
The unit may begin to display low-pressure alarms or show signs of short-cycling, where it switches on and off more frequently than usual. In some cases, ice may start to form on the evaporator coils. You might also detect unusual hissing sounds coming from the unit, or see signs of oil residue around joints, fittings or valves.
If any of these symptoms appear, it’s important to stop the system and arrange for a professional repair without delay.
The Risks of Ignoring a Refrigerant Leak
Overlooking a refrigerant leak can lead to wider system failure, meaning you’d need to replace it with a new chiller unit. A loss of refrigerant puts strain on the compressor, which may overheat or operate under low-pressure conditions, eventually causing burnout. In addition, leaks involving F-Gas refrigerants must be reported and rectified in accordance with legislation. Failure to comply can lead to penalties and invalidate system documentation.
How Refrigerant Leak Detection Works
Visual and Physical Inspection
The first step is often a close inspection of the chiller unit and pipework. Engineers check joints, welds, valves, and gauges for signs of oil residue, corrosion or physical wear. Ice formation or discolouration around key components may also indicate a slow leak.
Electronic and Gas Detection Methods
More advanced detection methods use electronic sniffers to detect escaping refrigerant vapour, as well as ultrasonic devices for pinpointing small leaks. In some cases, nitrogen pressure testing is used to trace leaks under controlled conditions. All testing and logging must meet F-Gas compliance standards and, ideally, will be carried out as part of a regular chiller maintenance regime.
Fixing a Refrigerant Leak: What to Expect
Once a leak is identified, a structured repair process typically includes:
- The leaking section of pipework or component is isolated and depressurised in a controlled manner.
- The fault is repaired or replaced, often using brazing, new fittings, or upgraded gaskets.
- The system is vacuum-tested to check for further leaks before recharging with refrigerant.
- Once pressure tested and verified, the unit is recommissioned and logged for compliance.
Prevention: How to Reduce the Risk of Future Leaks
Refrigerant leaks are often preventable. Routine inspections of pipework, vibration control measures and regular system testing all play a role in long-term reliability. Key prevention steps include:
- Checking refrigerant levels and pressure
- Verifying insulation and support brackets
- Scheduling F-Gas leak checks
- Recording all readings and interventions
Preventative maintenance can significantly reduce the chances of repeat leaks and help extend the working life of your chiller system. Contact us for more detailed advice with your commercial chiller system.
