Hantech 4619275 Bedienungsanleitungen Seite 21

5. Detection of flammable refrigerants
Under no circumstances shall potential sources of ignition be used in the searching for or
detection of refrigerant leaks. A halide torch (or any other detector using a naked flame)
shall not be used.
6. Leak detection methods
The following leak detection methods are deemed acceptable for systems containing
flammable refrigerants.
Electronic leak detectors shall be used to detect flammable refrigerants, but the
sensitivity may not be adequate, or may need re-calibration. (Detection equipment shall
be calibrated in a refrigerant-free area.) Ensure that the detector is not a potential source
of ignition 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
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.
7.
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;
EN
are suitable for
19
use with most refrigerants but the