CSR-20 & CSR-40, September 1999
Refrigeration System Diagnosis and Service
Heat Exchanger Replacement
6-21
Heat Exchanger Replacement
Removal
1.
Recover the refrigerant charge from the unit (see
“Refrigerant Recovery” in this chapter).
2.
Remove the “U” mounting clamps that hold the heat
exchanger assembly to the wall of the condenser section.
3.
Unsolder the liquid inlet and outlet line connections.
4.
Note position of feeler bulb on the side of the suction line.
Un-tape and remove the feeler bulb from the suction line.
5.
Unsolder the suction inlet and outlet line connections.
6.
Lift the heat exchanger assembly from the unit.
Installation
1.
Clean the tubes for soldering.
2.
Place the heat exchanger assembly in the unit and install
the mounting hardware.
3.
Solder the suction inlet and outlet line connections.
NOTE: Thermo King strongly recommends that
dry nitrogen be used to purge the system during
any solder operations (see “Using Pressurized
Nitrogen” in this chapter).
4.
Solder the liquid inlet and outlet line connections.
5.
Pressurize the refrigeration system and check for leaks
(see “Refrigerant Leak Test Procedure” in this chapter).
6.
If no leaks are found, recover the refrigerant used for the
leak test (see “Refrigerant Recovery” in this chapter).
7.
Evacuate the system (see “Evacuation and Cleanup of the
Refrigeration System” in this chapter).
8.
Clean suction line to a bright polished condition. Install
feeler bulb in the feeler bulb clamps on the suction line.
Locate bulb on the suction line in former position. The
feeler bulb must make good contact with the suction line
or operation will be faulty. Cover with insulating tape.
9.
Recharge the unit with R-404A (see “Refrigerant Charge” in
this chapter). Then perform a controller Pretrip Test to
verify system operation and correct feeler bulb installa-
tion.
Receiver Tank Replacement
Removal
1.
Recover the refrigerant charge from the unit (see
“Refrigerant Recovery” in this chapter).
2.
Unsolder the liquid inlet, liquid outlet and warm gas
bypass valve line connections.
3.
Loosen the mounting nuts and remove the tank.
4.
Remove the water fittings (option) and water pressure
switch (option) from the receiver tank for installation in
new tank.
Installation
1.
Install a new tank in the unit and tighten the mounting
bolts.
2.
Solder the inlet line, outlet line and warm gas bypass line
connections.
NOTE: Thermo King strongly recommends that
dry nitrogen be used to purge the system during
any solder operations (see “Using Pressurized
Nitrogen” in this chapter).
3.
Pressurize the refrigeration system and check for leaks
(see “Refrigerant Leak Test Procedure” in this chapter).
4.
If no leaks are found, recover the refrigerant used for the
leak test (see “Refrigerant Recovery” in this chapter).
5.
Evacuate the system (see “Evacuation and Cleanup of the
Refrigeration System” in this chapter).
6.
Recharge the unit with R-404A (see “Refrigerant Charge” in
this chapter). Then perform a controller Pretrip Test to
verify system operation.
