Doosan DX225LC, Manual, Page: 113 / 136

Electrical System SP000935
Page 112
3. Do not over tighten connections when working on
refrigerant system.
4. The new refrigerant system standards require new tools,
equipment and parts. DO NOT attempt to use equipment
use in servicing the old refrigerant system.
5. The new refrigerant oil (PAG type) has a high moisture
absorption characteristic. When the refrigerant system
vacuum seal has been broken, immediately plug up all
openings to prevent moisture from entering the system.
6. When joining unions which use O-ring seals, lightly coat
O-rings with refrigerant oil. Be careful not to drip oil on the
threads of the nut.
7. Be certain the O-rings are seated properly on the
refrigerant line lip. Always use new O-rings when
reassembling parts. Do not reuse old O-rings.
8. Use a vacuum pump to evacuate refrigerant system of air.
9. When charging the refrigerant system with the engine
running, do not open the high-pressure valve on the
manifold gauge as the reverse flow of high-pressure
refrigerant will rupture the hose.
10. When releasing the high-pressure hose after completing
the charging process, quickly disconnect the hose to
minimize refrigerant released to the air.
Repair and Replacement Procedure
1. Work Procedure
A. Before repairing or replacing any refrigerant
components first, return all refrigerant oil to the
compressor and perform recovery procedures.
2. Operating Condition
A. Run engine at maximum engine speed.
B. Select 'HI' blower fan speed and select A/C switch to
'ON'.
C. Set the temperature control switch for maximum
cooling and leave running for approximately 20
minutes.
NOTE:
The manifold gauge dial pointer can vary
depending on the outdoor temperatures.