VEVOR RT150CTW4 Bedienungsanleitung Seite 27

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 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.
14. Removal and evacuation:
When breaking into the refrigerant circuit to make repairs -or for any other purpose
-conventional procedures shall be used. However, for flammable refrigerants it is
important that best practice be followed, since flammability is a
consideration.
The following procedure shall be adhered to:
-safely remove refrigerant following local and national regulations; -evacuate;
-purge the circuit with inert gas (optional for A2L); -evacuate (optional for A2L);
-continuously flush or purge with inert gas when using flame to open circuit; and;
-open the circuit.
The refrigerant charge shall be recovered into the correct recov-ery cylinders if
venting is not allowed by local and national codes. For appliances containing
flammable refrigerants, the system shall be purged with oxygen-free nitrogen to
render the appliance safe for flammable refrigerants. This process might need to
be repeated several times. Compressed air or oxygen shall not be used for
purging refrigerant systems.
For appliances containing flammable refrigerants, refrigerants purging shall be
achieved by breaking the vacuum in the system with oxygen-free nitrogen and
continuing to fill until the working pressure is achieved, then venting to atmosphere,
and finally pulling down to a vacuum (optional for A2L). This process shall be
repeated until no refrigerant is within the system (optional for A2L).
When the final oxygen-free nitrogen charge is used, the system shall be vented
down to atmospheric pressure to enable work to take place.
The outlet for the vacuum pump shall not be close to any poten- tial ignition
sources, and ventilation shall be available.
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