Thermo King T-1000R, Maintenance Manual

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Refrigeration Maintenance 10-42
Installation
1. Apply a refrigerant Loctite to the threads of the HPCO.
2. Install and tighten the HPCO and reconnect the wires.
3. Pressurize the compressor and test for leaks.
4. If no leaks are found, back seat the refrigeration service valves and place the unit in operation. Check the refrigerant charge.
5. Perform a “Refrigerant Gauge Removal” procedure.
HIGH PRESSURE RELIEF VALVE REPLACEMENT
Determine the cause of extremely high discharge pressure before replacing the High Pressure Relief Valve.
Removal
1. Recover the refrigerant charge.
2. Unscrew and remove the high pressure relief valve from the receiver tank.
Installation
1. Apply a refrigerant oil to the O-ring of the high pressure relief valve.
2. Install and tighten the high pressure relief valve.
3. Pressurize the system and test for leaks.
4. If no leaks are found, replace the liquid line drier then evacuate the
system.
5. Recharge the unit with refrigerant and check the compressor oil.
6. Verify proper unit operation.
HOT GAS BYPASS SOLENOID (HGBS) TEST
1. Attach a gauge manifold to the suction service valve and the discharge service port. Attach another low pressure gauge to the
suction access port located in the suction line near the accumulator inlet. Low loss fittings must be used on the hoses connected
to the discharge service port and the suction access port.
2. Operate the unit with all zones in low speed cool.
3. Front seat the receiver tank outlet valve and allow the low side to pump down to 0 to 5 in. Hg vacuum (0 to -17 kPa).
4. Turn the unit Off.
5. Front seat the suction service valve to isolate the low side while it is still in a vacuum.
6. Watch the low pressure gauge attached to the suction access port. The low side pressure should not rise. It it does, there could
be a leak through one (or more) of following components: hot gas solenoids, purge valve, or hot gas bypass solenoid.
7. Check the temperatures of the refrigeration lines on each side of the HGBS by hand. A temperature difference between the
two sides of the HGBS indicates it is leaking.
8. Use the Mechanics/Premium HMI Control Panel to enter the Interface Board Test Mode. Refer to the appropriate
Microprocessor Diagnostic Manual for specific information about the Interface Board Test Mode.
9. From the Interface Board Test Mode select Hot Gas Bypass Solenoid.
10. Momentarily energize the HGBS with the Interface Board Test Mode by pressing the TEMP ON key. The low side pressure
should rise slightly. If the low side pressure does not rise, the HGBS is not opening. Check the continuity of the wiring and
the solenoid coil before assuming the solenoid is faulty.
11. Back seat the receiver tank outlet valve and the suction service valve. Perform a “Refrigerant Gauge Removal” procedure.
CAUTION: Do not run scroll compressor in a vacuum for more than 1 minute.