Thermo King SB-190 30, Manual

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Refrigeration Service Operations (Rev. 12/03)
71
2. Install the new drier and tighten the mounting hard-
ware.
3. Install and tighten the inlet nut. Hold the drier with a
back-up wrench on the hex behind the inlet fitting.
4. Release a small amount of refrigerant to purge the air
through the drier. Then tighten the outlet nut.
5. Pressurize the system and inspect for leaks. If no leaks
are found, open the refrigeration valves and place the
unit in operation.
EXPANSION VALVE ASSEMBLY
Removal
1. Pump down the low side and equalize the pressure to
slightly positive.
2. Remove the evaporator access panels.
3. Remove the feeler bulb from the clamp. Note the posi-
tion of the feeler bulb on the suction line.
4. Disconnect the equalizer line from the suction line.
5. Disconnect the inlet liquid line and unsolder the distrib-
utor from the expansion valve.
6. Remove the expansion valve mounting bolt and remove
the expansion valve from the unit.
Installation
1. Install and bolt the expansion valve assembly in the
unit.
2. Connect the inlet liquid line and solder the distributor
to the expansion valve.
3. Connect the equalizer line to the suction line.
4. Clean the suction line to a bright polished condition.
Install the feeler bulb clamps and the feeler bulb on the
side of the suction line in its former position. The feeler
bulb must make good contact with the suction line or
operation will be faulty. Wrap with insulating tape.
5. Pressurize the low side and test for leaks. If no leaks are
found, evacuate the low side.
6. Replace the access panels.
7. Open the refrigeration valves and place the unit in oper-
ation.
8. Test the unit to see that the expansion valve is properly
installed
HEAT EXCHANGER
Removal
1. Pump down the low side and equalize the pressure to
slightly positive.
2. Remove the upper and lower evaporator access panels.
1. End View
2. Side View
Location of Expansion Valve Bulb
AEA713