Ingersoll-Rand 900829, Maintenance Manual

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Refrigeration Maintenance
NOTE: The following procedures involve
servicing the refrigeration system. Some of these
service procedures are regulated by Federal, and
in some cases, by State and Local laws.
All regulated refrigeration service procedures
must be performed by an EPA certified
technician, using approved equipment and
complying with all Federal, State and Local
laws.
Evacuating and Charging the
Refrigeration System
Procedures
IMPORTANT: Thermo King Evacuation Station
P/N 204-725 and Evacuation Station Operation
and Field Application Instructions (TK-40612) is
required.
NOTE: The oil in the evacuation station vacuum
pump should be changed after each use.
Solenoid Valve Positions
The liquid injection valve and the defrost solenoid
must be in the open position during evacuation
procedures. These valves must be held open
manually using special magnet tools (P/N
204-1074) designed for this purpose.
NOTE: The condenser blocking solenoid is
normally open so it does not need to be held open
with a magnet tool.
1. Unscrew the solenoid coil retaining nut and
remove the coil assembly.
2. Place a magnet tool on the solenoid valve
stem.
3. Carry out the evacuation procedure.
4. After completing the evacuation procedure,
remove the magnet tools and replace the
solenoid coil assembly on the solenoid valve
and hand tighten the coil retaining nut.
Evacuation and Charging Procedure
The liquid line sight glass helps the operator to
determine the amount of charge under established
operating conditions. These units can be damaged
by an overcharge of refrigerant. The amount of
refrigerant the system can hold depends on circuit
volume which is affected by hose length.
The most satisfactory method of evacuating and
charging the system is as follows:
1. Connect a gauge manifold set to the suction
and discharge service ports on the engine
driven compressor.
2. Connect the center hose of the gauge manifold
to the manifold of an evacuation station. The
use of Thermo King Evacuation Station
P/N 204-725 is recommended.
3. Connect the hose from a drum of refrigerant to
the manifold of the evacuation station. Make
sure the valve on the refrigerant drum is
closed.
4. Open the valves on the gauge manifold and
the valves on the evacuation station.
5. Start the vacuum pump and evacuate the
system to 500 microns. After the system
reaches 500 microns, evacuate the system for
an additional hour.
NOTE: If the system will not come down to
500 microns, there is probably a leak in the
system or in the evacuation and charging
equipment hoses. Find and repair the leak.
Maintenance Inspection Schedule
Procedures Weekly Monthly
Semi-
Annual Annually
Check refrigerant level. • •
Replace dehydrator. •
Check compressor pressure regulator and suction
pressure regulator settings if applicable. •