工業冷水機製造商 LNEYA Taiwan
Refrigerant Leak in Chillers: Causes, Signs and What to Do
A refrigerant leak occurs when refrigerant escapes from a closed chiller system due to mechanical damage, poor sealing, or long-term wear. Refrigerant leaks can reduce cooling capacity, increase energy consumption, and cause compressor overheating or system failure. This article will take you to learn the causes and signs of refrigerant leakage and help you prevent it in advance.
Refrigerant Leak Symptoms in Chillers
One of the most obvious early signs of refrigerant leakage is a drop in refrigerant level or pressure. When you find the following problems with the chiller, it means that it has a risk of refrigerant leakage:
• Abnormal system pressure, both high and low pressures are low
• Water outlet temperature does not drop or fluctuates greatly
• System alarms, such as low-pressure protection and overheating protection
• Abnormal current fluctuations, frequent compressor starts and stops
• Persistent bubbling or no visible liquid in the sight glass
• When soapy water is used to detect the pipe interface, bubbles emerge
However, it should be noted that low refrigerant level is not necessarily caused by leakage. It may be that the installer did not set the liquid level correctly during installation.
Common Causes of Refrigerant Leaks in Chillers
1. Welding point cracking
If the welding quality of the refrigerant pipeline is not up to standard or fatigued after long-term use, leakage will occur near the U-bend, welding port, and pressure transmitter. When purchasing a chiller, you need to understand the manufacturer’s welding process quality. Reputable suppliers use stable brazing techniques and perform rigorous pressure tests to ensure system integrity.
2. Loose joints
The compressor can cause slight vibrations during operation, and the pipe thread will loosen or wear after a long time. This situation often occurs in variable frequency chillers and cooling systems that are not firmly fixed. Therefore, you need to install shock pads or spring supports for the equipment. And check whether there is a problem with pipe prestressing during installation.
3. Aging of gaskets
The gaskets of solenoid valves, expansion valves, filter driers and other components will age or harden after long-term hot and cold shocks. The resulting leaks are slow and difficult to detect in the early stages. You need better-performing sealing materials and a regular replacement plan.
4. Collision damage
If the internal pipes are hit during the transportation of the chiller, it will cause very obvious damage points and serious leaks. Therefore, wooden boxes are required for long-distance transportation. For chillers that need to be assembled on site, guardrails need to be added around the pipes to prevent collisions.
What to Do If a Refrigerant Leak Is Detected
After discovering refrigerant leakage, you need to turn off the power supply of the chiller immediately to prevent the compressor from idling. You should quickly evacuate the leakage point, open the doors and windows for ventilation, and avoid inhaling high-concentration refrigerant to avoid dizziness or poisoning.
If you are not a maintenance professional, it is dangerous to repair and refill the refrigerant yourself. You’d better write down the abnormal time, alarm code, and operating parameters, and provide them to the chiller supplier and professional maintenance personnel. This will help them determine the leak point and find a solution.
The biggest difficulty in repair is finding the leak point. Professional maintenance personnel usually use halogen leak detectors, electronic leak detectors, foam, etc. to confirm the leak point, and take measures such as re-welding, replacing pipe fittings, and tightening threads to repair it.
After the repair is completed, it is necessary to use a vacuum pump to evacuate the moisture and air in the pipeline and refill the refrigerant. After filling, perform pressure, current, and temperature control accuracy tests. It can only be put into use again after ensuring that there is no fault.
Note: If your chiller uses ammonia (R717), follow specific safety protocols and contact qualified technicians immediately.
| Refrigerant Type | Toxicity Level | Brief Description |
| R134a | Mildly toxic | High doses may affect the nervous system; safe under normal use |
| R22 | Mildly toxic | Regulated and being phased out due to environmental concerns |
| R410A | Mildly toxic | May cause suffocation at high concentrations |
| R407C | Mildly toxic | Similar to R22 with better environmental performance |
| R404A | Mildly toxic | May irritate respiratory tract in high concentrations |
| R1234yf | Mildly toxic | Low toxicity, but flammable; handle with care |
| R717 (Ammonia) | Toxic | Highly toxic and corrosive; requires professional handling |
| R744 (CO₂) | Non-toxic | High-pressure refrigerant; equipment must withstand pressure |
How to Prevent Refrigerant Leakage in Chillers
Prevention of refrigerant leakage is carried out throughout the entire process of design, installation, operation and maintenance.
Design and Installation
Refrigerant pipelines should be supported, shock absorbers should be installed near the compressor, and unsupported spans should be avoided to prevent continuous movement during operation. Because sharp turns or rigid connections near the compressor will increase stress concentration, which is a common leakage point.
Many leakage problems usually arise from insufficient cleaning of joints before brazing and welding, insufficient filling of fillers, or overheating of joints during installation. These joints can pass pressure tests, but they will leak due to repeated expansion and contraction after being put into use.
All pipe fittings, valves and connectors should be determined based on the operating pressure range of the system and the refrigerant used, especially in low-temperature or high-pressure chillers.
Regular inspection and maintenance
Early leaks can usually be detected through routine inspections. Oil stains around the joints, valves, compressor or heat exchanger connections are common signs of leakage. Pay attention to changes in suction and discharge pressures during regular inspections, even if the system still meets the cooling requirements, signs of refrigerant loss can be detected.
FAQs
Final Thought
LNEYA chillers are helium leak tested during production, and all brazing operations are performed by experienced technicians. This helps minimize the risk of refrigerant leakage during long-term operation.
