Komatsu PC450-8, Operation & Maintenance Manual

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MAINTENANCE
MAINTENANCE PROCEDURE
4-41
CHECK AND MAINTENANCE AIR CONDITIONER 4
Check Level of Refrigerant (gas)
WARNING
If the refrigerant used in the air conditioner gets into your eyes or on your hands, it may cause loss of
sight or frostbite. Do not touch the refrigerant. Never loosen any part of the refrigerant circuit.
Do not bring any flame close to any point where the refrigerant gas is leaking.
If the level of the refrigerant (gas) is low, the cooling effect
will be reduced. Run the engine at high idle, and check the
flow of the refrigerant gas (R134a) in the refrigerant circuit
through the sight glass (2) (inspection window) of the
receiver (1) when the cooler is running at high speed.
(A) No bubbles in refrigerant flow: Suitable
(B) Some bubbles in flow (bubbles pass continuously):
Lack of refrigerant
(C) Colorless, transparent: No refrigerant
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.
Inspection During 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.
Inspection and Maintenance Items
Check, maintenance items Content of check, maintenance
Guideline for maintenance inter-
val
Refrigerant (gas) Charge amount Twice a year (spring, autumn)
Air conditioner condenser Clogged fins Every 500 hours
Compressor Operating condition Every 4000 hours
V-belt Damage, tension Every 250 hours
Blower motor, fan
Operating condition
(does it make abnormal noise?)
When required
Control mechanism Operating condition (does it function normally?) When required
Piping mounts
Mounting condition, looseness at tightening or
connecting portions, leakage of gas, damage
When required