Mitsubishi Electric PAA-A18AA1 Manuel D'installation page 21

5.2. Devices that use R410A refrigerant
CAUTION
Install guidelines
• Do not use the existing refrigerant piping.
– The old refrigerant and refrigerant oil in the existing piping may contain a large amount
of contaminants which may cause the refrigerant oil of the new unit to deteriorate.
• 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 installation 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 contaminants 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
refrigerant 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.
• Always charge refrigerant in a liquid state.
– Charging refrigerant in the gaseous state will change the composition of the
refrigerant and lead to a performance drop.
Specifications are subject to change without notice.
PAA-A18, 24, 30, 36, 42AA1/BA1/CA1
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