into account the effects of aging or continual vibration from
sources such as compressors or fans.
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.
Leak detection methods. T
he
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. L
eak
detection
equipment
shall
be
set
at
a
percentage
of
the if 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. O
xygen free nitrogen (ofn) shall then be
purged through the system both
before and during the
brazing process.
Removal and evavuation. 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
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