Precautions For Devices That Use R410A Refrigerant - Mitsubishi Electric CITY MULTI PAC-AH001-1 Installation Manual

Precautions for devices that use R410A refrigerant

CAUTION
• Do not use the existing refrigerant piping.
- The old refrigerant and refrigerator oil in the existing piping contains a large amount of
chlorine which may cause the refrigerator oil of the new unit to deteriorate.
• Use refrigerant piping made of C1220 (Cu-DHP) phosphorus deoxidized copper as
specified in the JIS H3300 "Copper and copper alloy seamless pipes and tubes". In
addition, be sure 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
contaminant.
- 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 and compressor
trouble may result.
• Use ester oil, ether oil or alkylbenzene (small amount) as the refrigerator oil to coat
flares and flange connections.
- The refrigerator oil will degrade if it is mixed with a large amount of mineral oil.
• 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.
• Do not use a refrigerant other than R410A.
- If another refrigerant (R22, etc.) is used, the chlorine in the refrigerant may cause the
refrigerator oil to deteriorate.
• 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 conventional refrigerants. (Gauge
manifold, charge hose, gas leak detector, reverse flow check valve, refrigerant charge
base, vacuum gauge, refrigerant recovery equipment.)
- If the conventional refrigerant and refrigerator oil are mixed in the R410A, the
refrigerant may deteriorated.
- If water is mixed in the R410A, the refrigerator oil may deteriorate.
- Since R410A does not contain any chlorine, gas leak detectors for conventional
refrigerants will not react to it.
• Do not use a charging cylinder.
- Using a charging cylinder may cause the refrigerant to deteriorate.
• Be especially careful when managing the tools.
- If dust, dirt, or water gets in the refrigerant cycle, the refrigerant may deteriorate.
PAC-AH001-1
11 © 2017 Mitsubishi Electric US, Inc.