Komatsu D375A-8, Operation & Maintenance Manual

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Check and mainte-
nance items
Content of check and maintenance Guideline for maintenance interval
Blower motor, fan Operating condition (Check for unusual
noise) When required
Control mechanism Operating condition (Check that function
is normal) When required
Piping mounts Mounting condition, looseness at tighten-
ing or connecting portions, leakage of
gas, damage When required
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.
METHOD FOR CHECKING LEVEL OF REFRIGERANT (GAS)
k k
WARNING
• Always handle the refrigerant (gas) according to the local regulations.
• If the refrigerant used in the air conditioner gets into your eyes or is splashed on your hands, it may
cause loss of sight or frostbite. Never touch the refrigerant. Do not loosen any part of the refrigerant
circuit.
• Do not bring open flame close to a refrigerant leaking point.
If the level of the refrigerant (gas) is low, the cooling effect will be reduced. Perform while running the engine at
high idle and operating the air conditioner at high speed.
Check the condition of the refrigerant gas (Hydrofluorocarbons
HFC -134a) that circulates the refrigerant circuit, through sight
glass (2) (inspection window) of receiver (1).
(A) No bubbles in refrigerant flow: Suitable
(B) Some bubbles in refrigerant flow: In sufficient (bubbles pass
continuously)
(C) Colorless, transparent: No refrigerant
REMARK
When there are bubbles, the refrigerant gas is insufficient. In this case, ask your Komatsu distributor to add re-
frigerant. If the air conditioner is run with the refrigerant gas level low, it will cause damage to the compressor.
Use Hydrofluorocarbons HFC -134a as refrigerant.
METHOD FOR CLEANING AIR CONDITIONER AIR FILTERS (FRESH/RECIRC)
When the air conditioner air filter is clogged and the air conditioner does not work well, clean the air filter.
MAINTENANCE MAINTENANCE PROCEDURE
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