Precautions For Disconnecting And Connecting Refrigerant Piping - Komatsu PC88MR-10 Shop Manual

Precautions for disconnecting and connecting refrigerant piping

K5B0-924-K-00-A)
When replacing the air conditioner unit, air conditioner compressor, condenser or receiver drier,
etc., collect the refrigerant (air conditioner gas: R134a) from the air conditioner circuit before
disconnecting the air conditioner hoses.
a Ask a qualified person for collecting, adding and filling operations of the refrigerant (air conditioner gas:
R134a). (Only registered persons can work.)
a Never release the refrigerant (air conditioner gas: R134a) to the atmosphere.
If refrigerant gas (air conditioner gas: R134a) gets in your eyes, you may lose your sight. And if it
touches your skin, you may suffer from frostbite. Put on protective eyeglasses, gloves and
working clothes with long sleeves while collecting the refrigerant or filling the air conditioner
circuit with the refrigerant.
Disconnection
Although the refrigerant (air conditioner gas: R134a) used on the machine's air conditioner is less
destructive to the ozone layer for environmentally friendliness, it is not allowed to be released into
the atmosphere as is. Whenever disconnecting the air conditioner gas circuit, be sure to recover
the refrigerant gas to reuse it.
a Ask a qualified person for collection and charge of the refrigerant (air conditioner gas: R134a).
a Never release the refrigerant (air conditioner gas: R134a) to the atmosphere.
If the refrigerant (air conditioner gas: R134a) gets in your eyes, you may lose your sight. Also, if
your skin is exposed to the gas, you may suffer from frostbite. Accordingly, put on protective
eyeglasses, gloves and working suits with long sleeves while you are collecting or filling
refrigerant.
When loosening the nuts fixing air conditioner hoses and tubes, be sure to use 2 wrenches; use one
wrench to fix and use the other one to loosen the nut.
For the disconnected air conditioner piping, plug ends to prevent dirt, dust, and water from entering the
hose.
Connection
Once an O-ring is used, it is deformed and deteriorated. Accordingly, do not reuse it.
When removing it, use a soft tool (such as a toothpick) so that the piping will not be damaged.
Check that the O-ring is not damaged or deteriorated.
Apply compressor oil (ND OIL8) for refrigerant (R134a) to the O-ring. (See item 4 of "Handling of
compressor oil".)
a However, do not apply oil to the threaded portion of a bolt, nut or union.
Check that the O-rings are fitted to the joints when connecting the air conditioner piping.
When tightening nuts of the air conditioner hoses and tubes, be sure to use 2 wrenches. Use one wrench
to fix and tighten the nut with the other wrench to the specified torque (Use a torque wrench for tightening).
a Example of fitting of O-ring
An O-ring is fitted to every joint of the air conditioner piping.
PC88MR-10
Precautions for disconnecting and connecting
80 Appendix
refrigerant piping
(PC88MR-
80-81