2
Warnings (for using R290 refrigerant only)
and is suitable for the refrigerant used. Leak detection equipment
shall be set at a percentage of the LFL of the refrigerant and shall
be calibrated to the refrigerant employed and the appropriate
percentage of gas (25 % maximum) is confirmed. Leak detection
fluids are suitable for use with most refrigerants but the use of
detergents containing chlorine shall be avoided as the chlorine may
react with the refrigerant and corrode the copper pipe-work. If a
leak is suspected, all naked flames shall be removed/ extinguished.
If a leakage of refrigerant is found which requires brazing, all of
the refrigerant shall be recovered from the system, or isolated
(by means of shut off valves) in a part of the system remote from
the leak. Oxygen free nitrogen (OFN) shall then be purged through
the system both before and during the brazing process.
12. Removal and evacuation
When breaking into the refrigerant circuit to make repairs or for any
other purpose conventional procedures shall be used. However, it
is important that best practice is followed since flammability is a
consideration. The following procedure shall be adhered to:
•Remove refrigerant;
•Purge the circuit with inert gas;
•Evacuate;
•Purge again with inert gas;
•Open the circuit by cutting or brazing.
The refrigerant charge shall be recovered into the correct recovery
cylinders. The system shall be flushed with OFN to render the
17 / 92 EN
Portable air conditioner / Instruction Manual