Devices That Use R410A Refrigerant - Mitsubishi Electric PAA-A18AA1 Service Manual

1.2. Devices that use R410A refrigerant

CAUTION
Service guidelines
• Use refrigerant piping made of C12200 (Cu-DHP) phosphorus deoxidized copper as
specified in the ASTM B280 Standard Specification for Seamless Copper Tube for Air
Conditioning and Refrigeration Field Service. Ensure that the inner and outer surfaces of
the pipes are clean and free of hazardous Sulphur, oxides, dust/dirt, shaving particles,
oils, moisture or any other contaminants.
– Contaminants on the inside of the refrigerant piping may cause the refrigerant residual
oil to deteriorate.
• Store the piping to be used during service indoors and keep both ends of the piping
sealed until just before brazing. (Store elbows and other joints in a plastic bag.)
– If dust, dirt, or water enters the refrigerant cycle, deterioration of the oil will result in
malfunction of the compressor.
• Do not use a refrigerant other than R410A.
– If any other refrigerant is used, the chlorine in that refrigerant may cause the
refrigerant oil to deteriorate.
– Since R410A does not contain any chlorine, gas leak detectors for conventional
refrigerant will not react to it.
• Use a vacuum pump with a reverse flow check valve.
– The vacuum pump oil may flow back into the refrigerant cycle and cause the
refrigerator oil to deteriorate.
• Do not use the following tools that are used with refrigerants other than R410A:
– Gauge manifold, charge hose, gas leak detector, reverse flow check valve, refrigerant
charge base, vacuum gauge, refrigerant recovery equipment.
• Do not use a charging cylinder.
– It may cause the refrigerant to deteriorate.
• Use liquid refrigerant to fill the system.
– If gas refrigerant is used to seal the system, the composition of the refrigerant in the
cylinder will change and performance may drop.
Specifications are subject to change without notice.
PAA-A18, 24, 30, 36, 42AA1/BA1/CA1
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