Komatsu H70051 Series Operation & Maintenance Manual page 350

MAINTENANCE PROCEDURE
6.
Open the engine side cover (4) on the left side of the ma-
chine.
7.
Check the condition of the refrigerant gas (Hydrofluorocar-
bons HFC-134a) that circulates the refrigerant circuit,
through the sight glass (6) (inspection window) of the re-
ceiver drier (5).
(A) Just after the air conditioner switch is turned on, a
small number of bubbles are seen. After a while, the
sight glass becomes milky white, and then becomes
pale: Appropriate
(B) After the air conditioner switch is turned on, bubbles
are seen continuously: Insufficient
Condition viewed through the
sight glass
4-38
Bubbles are seen: Gaseous and liquid refrigerants are mixed.
No bubble: All refrigerant becomes liquid and transparent.
State of refrigerant flow
MAINTENANCE