Thermo King Spectrum DE 30-2, Manual, Page: 87 / 140

Refrigeration Service Operations
87
High Pressure Cutout Switch
and High Pressure Switch
Removal
1. Pump down the low side and equalize the
pressure to slightly positive.
2. Front seat the discharge and suction service
valves. Remove the remaining refrigerant
from the compressor.
3. Disconnect the wires and remove the switch
from the compressor discharge manifold.
Installation
1. Apply a refrigerant Loctite to the threads of
the switch.
2. Install and tighten the switch and reconnect
the wires.
3. Pressurize the compressor and test for leaks.
4. If no leaks are found, open the refrigeration
service valves and place the unit in operation.
Check the refrigerant charge and the
compressor oil, and add as required.
Discharge Pressure Sensor
Removal
1. Recover the refrigerant charge.
2. Disconnect the wire connector from the
discharge pressure sensor.
3. Remove the mounting clamp (if used) from
the discharge pressure sensor.
4. Unscrew the discharge pressure sensor from
the adapter on the end of the tube. Use a
backup wrench to hold the adapter.
5. Remove the discharge pressure sensor.
Installation
1. Apply refrigerant Loctite to the threads on the
discharge pressure sensor.
2. Screw the discharge pressure sensor into the
adapter on the end of the tube. Use a backup
wrench to hold the adapter.
3. Install the mounting clamp (if used) for the
discharge pressure sensor.
4. Recharge the unit with the proper refrigerant
and check the compressor oil.
High Pressure Relief Valve
Removal
1. Recover the refrigerant charge.
2. Unscrew and remove the high pressure relief
valve. It is located near the top of the receiver
tank.
Installation
1. Apply a refrigerant oil to the O-ring of the
high pressure relief valve.
2. Install and tighten the high pressure relief
valve.
3. Pressurize the refrigeration system and test for
leaks. If no leaks are found, evacuate the
system.
4. Recharge the unit with the proper refrigerant
and check the compressor coil.
Throttling Valve
See Figure 58 on page 88 for an illustration of the
throttling valve assembly.
Removal
1. Pump down the low side and equalize the
pressure to slightly positive.
2. Front seat the discharge and suction service
valves. Recover the refrigerant remaining in
the compressor.
3. Remove the suction service valve.
4. Unbolt and remove the throttling valve from
the unit.