Thermo King SLXi Spectrum, Maintenance Manual

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Refrigeration Maintenance 10-3
Refrigeration Maintenance Procedures
The following procedures can be found in the Thermo King Truck and Trailer Diagnosing Manual TK 60201-8-OD
1. Installing Gauge Mainfold
2. Compressor Pump Down and Checkout
3. Low Side Pump Down
Additional Information Low Side Pump Down for TCI and SPECTRUM Models
1. Install a gauge manifold at the compressor.
2. Operate all compartments in COOL for 10 minutes or more. Then front seat the receiver tank outlet valve and bypass hand
valve, and pump down the low side to a -0.68 to -0.85 bar, 20 to 25 in. Hg vacuum. Turn all compartment On/Off switches
OFF.
If the unit pumps down acceptably and then holds at least a , -0.51 bar, 15 in. Hg vacuum for 2 minutes or more, it can be
assumed that the receiver tank outlet valve, the compressor discharge valve plates, the hot gas solenoid, the Hot Gas Bypass
valve, the rear (and center) hot gas solenoid and the purge valve solenoid (TCI and SPECTRUM models) are sealing properly.
3. Prepare to perform service on the unit’s low side by equalizing the high side and low side pressures.
a. Disconnect the purge valve solenoid wires from the main wire harness (TCI and SPECTRUM models).
b.Disconnect the Hot Gas Bypass valve solenoid wires from the main wire harness (for applicable Spectrum units).
c. Keep Zone 1 setpoint adjusted to require COOL and turn the front compartment On/Off switch ON.
d.Adjust the Zone 2 setpoint to require HEAT. Then turn the rear compartment On/Off switch ON for 1/2 second and then
OFF again. The high pressure gauge will indicate a pressure decrease and the low pressure gauge will indicate a pressure
increase when the Zone 2 hot gas solenoid opens.
e. Adjust the Zone 3 setpoint (if so equipped) to require HEAT. Then turn the center compartment On/Off switch ON for 1/2
second and then OFF again. The high pressure gauge will indicate a pressure decrease and the low pressure gauge will
indicate a pressure increase when the Zone 3 hot gas solenoid opens.
f. Adjust the Zone 1 setpoint to require HEAT. Then turn the front compartment On/Off switch ON for 1/2 second and then
OFF again. The high pressure gauge will indicate a pressure decrease and the low pressure gauge will indicate a pressure
increase when the Zone 1 hot gas solenoid opens.
g.Adjust all zone setpoints to require HEAT. Then turn all compartment On/Off switches ON. Equalise the low side pressure
to 0.07 to 0.14 bar, 1 to 2 psi. Then turn all Zone On/Off switches OFF.
NOTE: If the compartment temperatures are high, the hot gas solenoids (Zones 1, 2 and 3) must be energised with a test lead.