6-22
High Pressure Switch Replacement
Refrigeration System Diagnosis and Service
CSR-20 & CSR-40, September 1999
High Pressure Cutout Switch Replacement
Removal
1.
Recover the refrigerant charge from the unit (see
“Refrigerant Recovery” in this chapter).
2.
Turn the unit On-Off switch OFF. Disconnect electrical
connections to the switch.
3.
Unsolder the high pressure cutout switch from the unit.
Installation
1.
Clean the tube for soldering.
2.
Place the new switch in position and solder the liquid line
connection.
CAUTION: Use a heat sink or wrap the switch
with wet rags to prevent damage to the new
switch.
3.
Pressurize the high side with refrigerant and check for
leaks (see “Refrigerant Leak Test Procedure” in this chap-
ter).
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.
Reconnect the electrical wires to the switch.
7.
Recharge the unit with R-404A (see “Refrigerant Charge” in
this chapter). Then perform a controller Pretrip Test to
verify system operation.
Warm Gas Bypass Solenoid Valve, Liquid
Injection Valve or Dehumidify Valve (Option)
Replacement
NOTE: In most cases, only the coil requires replace-
ment. No other repair is possible on solenoid
valves.
Removal
1.
Recover the refrigerant charge from the unit (see
“Refrigerant Recovery” in this chapter).
2.
Turn the unit On-Off switch OFF. Disconnect electrical
connections to valve coil.
3.
Dehumidify valve: Remove insulating tape from liquid
line.
4.
Unsolder the liquid line connections to the valve.
5.
Remove the valve from the unit.
Installation
1.
Clean the tubes for soldering.
2.
Place the new valve in position and solder the liquid line
connections.
CAUTION: Use a heat sink or wrap the valve with
wet rags to prevent damage to the new valve.
3.
Pressurize the low side with refrigerant 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.
Reconnect the electrical wires to the valve.
7.
Recharge the unit with R-404A (see “Refrigerant Charge” in
this chapter). Then perform a controller Pretrip Test to
verify system operation.
