Thermo King 919180, Руководство пользователя

Страница: 106 / 148

Refrigeration Service Operations
106
Cleaning In-line Screen
1. Perform a low side pump down; bleed
pressure back to 1 psig (7 kPa).
2. Remove the liquid line fitting.
3. A small tool with a slight hook may be needed
to pull screen from the expansion valve.
4. Clean the screen and reinstall.
NOTE: Outlet screen points toward the
distributor.
Heat Exchanger
Removal
1. Remove the refrigerant charge.
2. Remove the evaporator top cover.
3. Remove the mounting bolts that hold the heat
exchanger on the bulkhead.
4. Disconnect the equalizer line from the suction
line.
5. Disconnect liquid outlet line flare nut from the
expansion valve.
6. Note the position of the feeler bulb on the side
of the suction line. Remove the expansion
valve feeler bulb from the suction tube.
7. Unsolder the suction line at the evaporator coil
end.
8. Unsolder the remaining outlet suction line and
inlet liquid line connections from the
condenser side of the bulkhead. Remove putty
from around the lines before unsoldering the
connections.
9. Lift the heat exchanger assembly out of the
evaporator housing.
Installation
1. Clean the tubes for soldering.
2. Place the heat exchanger assembly in the
evaporator housing and install the mounting
hardware loosely.
3. Solder liquid inlet and suction outlet line
connections on the condenser side of the
bulkhead. Seal openings through bulkhead
with putty when refrigerant lines have cooled
off.
4. Tighten the heat exchanger mounting
hardware securely.
5. Solder suction line connection to the
evaporator coil.
6. Connect the equalizer line flare fitting to the
suction line and liquid outlet line flare fitting
to the expansion valve.
7. Pressurize the low side and test for leaks. If no
leaks are found, evacuate the unit.
8. Clean the suction tube to a bright polished
condition. Install the feeler bulb clamps and
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.
9. Open the refrigeration valves and place the
unit in operation. Install refrigerant charge.
10. Test the unit to see that the expansion valve is
properly installed.
1. Solder-in Expansion Valve Screen
2. Solder-in Type
Figure 65: Expansion Valve