ICESQUARE / Quality
Leak testing a refrigeration system
A leak test checks whether the circuit holds pressure and helps locate leaks before evacuation and charging. The test criteria depend on the equipment, the section under test and its components.
- Isolate the section
- Pressurize per manual
- Check for leaks
- Record
Define the section and its limit
After recovering refrigerant where applicable, identify the test section and confirm the test pressure, hold period and components to isolate. In systems with multiple pressure levels, verify each side’s limits separately. Use regulated dry nitrogen and suitable instruments. Never use oxygen or compressed air to pressurize a refrigerant circuit.
Stabilize and look for leaks
Raise pressure in stages according to the procedure. Record pressure and temperature after stabilization. Check joints, valves and service fittings using a compatible leak detection solution or the manufacturer’s approved method. Remember that gas pressure changes with temperature.
Document the result
Record the section, starting and ending pressure and temperature, elapsed time, method and result. If you find a leak, depressurize before repairs and retest afterward. Proceed to evacuation once the leak test passes.
Guide for trained technicians. Follow the manufacturer’s procedure and limits for the refrigerant and equipment model being serviced.
Technical references
- Daikin · Three-Phase Installation Instructions · IO-D-4045A · “Brazing”, “Leak Testing”, “Evacuation”
- Danfoss · Cold Room Refrigeration Systems · “Commissioning”