Thermo King T-1080S, Maintenance Manual

Page: 154 / 191

Refrigeration Service Procedures
153
3. Remove liquid injection solenoid mounting
bolts and remove the liquid injection solenoid
from the unit.
Installation
1. Install and bolt the liquid injection solenoid
assembly in the unit.
2. Solder (95-5 Solder) the inlet liquid line and
the outlet line to the injection solenoid.
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. Test the unit to see that the valve is properly
installed.
Purge Valve (PV) 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 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 solenoid, liquid injection
solenoid, purge valve, or receiver tank
pressure check valve.
7. Check the temperatures of the refrigeration
lines on each side of the PV by hand. A
temperature difference between the two sides
of the PV 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
Purge Valve.
10. Momentarily (for approximately 1 second)
energize the PV with the Interface Board Test
Mode. The low side pressure should rise
slightly. If the low side pressure does not rise,
the PV 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.
Receiver Tank Pressure Check
Valve 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 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
CAUTION: Do not run scroll compressor
in a vacuum for more than 1 minute.
CAUTION: Do not run scroll compressor
in a vacuum for more than 1 minute.