Piping Machining - Mitsubishi Electric CITY MULTI PUHY-400YMF-B Service Handbook

[2] Piping Machining

Use ester oil, ether oil or alkylbenzene (small amount) as the refrigerator oil to coat flares and flange connections.
Reason:
1. The refrigerator oil used for the equipment is highly hygroscopic and may introduce water inside.
Notes:
• Introducing a great quantity of mineral oil into the refrigerant circuit may also cause a compressor failure.
• Do not use oils other than ester oil, ether oil or alkylbenzene.
Use only the necessary minimum quantity of oil !
–3–