Publicidad
Idiomas disponibles
Idiomas disponibles
• Intrinsically components are the only types that can be worked on while live in the presence
of a flammable atmosphere.The test apparatus shall be at the correct rating.
• Replace components only with parts specified by manufacturer. Other parts may result in
the ignition of refrigerant in the atmosphere from a leak.
1 1 . CAB LI N G
• Check that cabling will not be subject to wear, corrosion, excessive pressure, vibration,
sharp edges or any other adverse environmental effects. The check shall also take into
account the effects of aging or continual vibration from sources such as compressors or
fans.
1 2. L EAK AGE D E T ECT I O N F OR F L AMMA B L E R E F R IG E R A NT S
• 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.
1 3 . LEAK DE TECT IO N ME T HO DS
The following leak detection methods are acceptable for systems containing flammable
refrigerant.
• Electronic leak detectors shall be used to detect flammable refrigerants, but the sen-
sitivity may not be adequate, or may need recalibration (Detection equipment shall be
calibrated in a refrigerant-free area.) Ensure that detector is not a potential source of
ignition and is suitable for the refrigerant used.
• Leak detection fluids are suitable for use with most refrigerants but the use of deter-
gents 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 leak of refrigerant is found which requires brazing, all of the refrigerant shall be re-
covered from the system. Oxygen free nitrogen (OFN) shall then be purged through the
system both before and during the brazing process.
1 4 . RE M OVAL AND E VACUAT I O N
• When breaking into the refrigerant circuit to make repairs-or for any other purpose-con-
ventional 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 unit safe. This process may need to be repeated
several times. Compressed air or oxygen shall not be used for this task.
• Flushing shall be achieved by breaking the vacuum in the system with OFN and continu-
ing to fill until the working pressure is achieved , then venting to atmosphere, and finally
pulling down to a vacuum. This process shall be repeated until no refrigerant is within the
E NGL I SH
14
Publicidad
