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PAW-VP•LDHW - Technical Manual – 2020-07
Safety Instructions
When Connecting Refrigerant Tubing
DANGER
● When performing piping work, do not mix air with specified refrigerant (R410A or
R32, depending on the outdoor unit model) in refrigeration cycle. It result in re-
duced capacity, and risk of explosion and injury due to high pressure inside the
refrigerant cycle.
● If the refrigerant comes in contact with a flame, it produces a toxic gas.
● Do not add or replace refrigerant other than specified type. It may cause product
damage, burst and injury, etc.
●
Ventilate the room immediately, in the event that refrigerant gas leaks during the
installation. Be careful not to allow contact of the refrigerant gas with a flame as
this will cause the generation of toxic gas.
●
Keep all tubing runs as short as possible.
● Apply refrigerant lubricant to the matching surfaces of the flare and union tubes
before connecting them, then tighten the nut with a torque wrench for a leak-free
connection.
●
Check carefully for leaks before starting the test run.
●
Do not leak refrigerant while piping work for an installation or re-installation, and
while repairing refrigeration parts. Handle liquid refrigerant carefully as it may
cause frostbite.
●
Under no circumstances shall potential sources of ignition be used in the searching
or detection of refrigerant leaks.
● A halide torch (or any other detector using a naked flame) shall not be used.
●
Electronic leak detectors may be used to detect refrigerant leaks but, the sensitivity
may not be adequate, or may need re-calibration. (Detection equipment shall be
calibrated in a refrigerant-free area.)
●
Isolate the electrical supply to the unit (power OFF), before opening the unit to
check or repair electrical parts and wiring.
● Keep your fingers and clothing away from any moving parts.
● Clean up the site after you finish, remembering to check that no metal scraps or
bits of wiring have been left inside the unit being serviced.
●
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 lower flammable limit
(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.
