Install Instructions

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Safety Precautions
Page 9
WARNING (for using R290/R32 refrigerant only, continued)
8. Repair to Intrinsically Safe Components
DO NOT apply any permanent inductive or capacitance loads to the circuit without ensuring that
the permissable voltage current permitted for the equipment in use will not be exceeded.
Intrinsically safe components are the only types of components that can have worked performed
on them while live and in the presence of a flammable atmosphere. The test apparatus should be
at the correct rating. Ensure any components that need to be replaced are only replaced with
parts specified by the manufacturer. If specified parts are not used, it could result in the ignition of
refrigerant from a leak.
9. Cabling
Ensure cabling will not be subject to wear, corrosion, excessive pressure, vibration, sharp edges,
or any other adverse environmental effects. You should also take into account the effects of aging
or continual vibration from sources such as compressors or fans.
10. Detection of Flammale Refrigerants
DO NOT use potential sources of ignition (ex: halide torch, or any other detector which uses an
open flame) while attempting to search for or detect refrigerant leaks.
11. Leak Detection Methods
The following methods of leak detection have been deemed acceptable for systems containing
flammable refrigerants. Electronic leak detectors should be used to detect flammable refrigerants,
however, the sensitivity may not be adequate, or it could need recalibration. If recalibration is
needed, it should be calibrated in a refrigerant-free environment. Ensure the detector is not a
potential source of ignition, and is suitable for the type of refrigerant used. Leak detection
equipment should be set at a percentage of the LFL of the refrigerant, and should be calibrated to
the refrigerant used and the appropriate percentage of gas (25% maximum) is confirmed. Leak
detection fluids are suitable for use with most refrigerant, but the use of detergents containing
chlorine should be avoided, because the chlorine could react with the refrigerant and cause the
copper piping to corrode. If a leak is suspected, any open flames should be removed or
extinguished from the area. If a leak is found, which will require brazing, all of the the refrigerant
should be recovered from the system, or isolated (by shutting off the valves) in a part of the
system that is separated from the leak. Oxygen Free Nitrogen (OFN) should then be purged
through the system before and during the brazing process.
12. Removal and Evacuation
When it is needed to enter the refrigerant circuit to make repairs, or for any other purpose,
conventional procedures should be used. However, it is important to follow the best practice
because of the flammable properties of the refrigerant. Opening refrigerant systems should not
be completed by brazing. Use the following steps:
1.) Remove refrigerant
2.) Purge the circuit with inert gas
3.) Evacuate the system
4.) Purge the cicuit again with inert gas
5.) Enter the circuit by cutting or brazing
The refrigerant should be recovered into the correct recovery cylinders. The system should be
flushed with OFN to render the unit safe. This process may need to be repeated several times.
DO NOT use compressed air or oxygen for this task.