Komatsu D475A-5E0, Operation & Maintenance Manual

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MAINTENANCE
SERVICE PROCEDURE
CHECK AND ADJUST AIR CONDITIONER
CHECK TENSION OF COMPRESSOR BELT
If the belt is loose, it will slip and the cooling effect will be reduced. From time to time, press a point midway between
the altenator drive pulley and compressor pulley with your finger and check that the tension.
When the belt is new, there will be initial elongation, so always adjust again after 2 or 3 days.
For check tension of belt, see "CHECKING (PAGE 4-62)".
CHECK LEVEL OF REFRIGERANT(GAS)
WARNING
When handling refrigerant gas, always follow local laws and
regulations.
The refrigerant used in the cooler is colorless and odorless and does
not harm the atmosphere, but if the liquid gets into your eyes or on your
hands, it may cause loss of sight or frostbite, so never loosen any part
of the refrigerant circuit.
If the level of the refrigerant (gas) is low, the cooling effect will be
reduced. Run the engine at High idle (MAX), and check the flow of
the refrigerant gas (Hydrofluorocarbons HFC-134a) in the
refrigerant circuit through sight glass (2) (inspection window) of
receiver (1) when the cooler is running at high speed.
(A) Correct: No bubbles are included in the flow
(B) Low: Bubbles are included in the flow
(bubbles pass continuously)
(C) None: Colorless, transparent
REMARK
When there are bubbles, the refrigerant gas level is low, so contact your Komatsu distributors to have refrigerant
added. If the air conditioner is run with the refrigerant gas level low, it will cause damage to the compressor.
Charge amount of air conditioner refrigerant (gas): 1,100 g (2.4 lb)
OPERATING AIR CONDITIONER OFF-SEASON
Even during the off-season, operate the air conditioner for 3 to 5 minutes once a month to maintain the oil film at all
parts of the compressor.
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