Thermo King UT-1200, Manual

Page: 126 / 169

Refrigeration Service Procedures
126
compressor is probably faulty if it cannot raise
the head pressure by 100 psig (689 kPa) or to
375 psig (2586 kPa).
Compressor Replacement
Removal
1. Recover the refrigerant charge.
2. Loosen and remove the electric
motor/compressor belt from the compressor
pulley.
3. Unsolder the discharge line and the liquid
injection line from the compressor.
4. Unbolt the suction valve from the compressor.
5. Disconnect the compressor temperature sensor
wires.
6. Remove the compressor mounting bolts.
7. Lift the compressor out of the unit. Keep the
compressor ports covered to prevent dust, dirt,
etc., from falling into the compressor.
Installation
1. Lift the compressor into the unit and install
the mounting bolts.
NOTE: New compressors are shipped with a
full oil charge. Install the new compressor
with the full oil charge and check the oil
level after operating the unit for at least 30
minutes.
2. Install the suction service valve using new
gaskets soaked in refrigeration oil.
3. Reconnect the compressor temperature sensor
wires.
4. Reconnect (solder) the discharge line and the
liquid injection line.
5. Pressurize the system and test for refrigerant
leaks.
6. If no leaks are found, replace the liquid line
drier then evacuate the system.
7. Replace the compressor/electric motor belt
and adjust the tension.
8. Recharge the unit with the proper refrigerant.
9. Operate the unit at least 30 minutes and then
inspect the oil level in the compressor. Add or
remove oil if necessary.
10. Check the refrigerant charge and add
refrigerant if needed.