Thermo King CRR-40 119, Руководство пользователя

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Refrigeration Maintenance and Service Operations
143
4. Solder equalizer line to expansion valve.
5. Clean the suction line to a bright polished
condition. Install the feeler bulb of new power
head in the feeler bulb clamp 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.
6. Pressurize the low side and test for leaks (see
“Refrigerant Leak Test Procedure” in this
chapter).
7. If no leaks are found, recover the leak test gas
(see “Refrigerant Recovery” in this chapter).
8. Evacuate the low side (see “Evacuation and
Cleanup of the Refrigeration System” in this
chapter).
9. Cover expansion valve outlet line with
insulating tape.
10. Open the liquid line service valve and place
the unit in operation.
11. Operate the unit and note the suction pressure
and container temperature to see that the
expansion valve is properly installed and that
the feeler bulb is properly located.
Heat Exchanger Replacement
Removal
1. Close the liquid line service valve and pump
down the low side to -35 kPa, -0.35 bar, 10 in.
vacuum. Break the vacuum with nitrogen
between 10 and 20 kPa, 0.10 and 0.20 bar, 1
and 3 psig.
2. Remove the “U” mounting clamps that hold
the heat exchanger assembly to the wall of the
condenser section.
3. Heat and unsolder 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. Heat and unsolder the suction 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 line connections.
NOTE: It is strongly recommended that dry
nitrogen be used to purge the system during
any solder operations (see “Using
Pressurized Nitrogen” in this chapter).
NOTE: If pressurizing with nitrogen, front
seat the discharge valve to prevent nitrogen
from entering the refrigerant charge.
4. Solder the liquid line connections.
5. Pressurize the low side and check for leaks
(see “Refrigerant Leak Test Procedure” in this
chapter).
6. If no leaks are found, recover the leak test gas
(see “Refrigerant Recovery” in this chapter).
7. Evacuate the low side (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. Open the liquid line service valve and place
unit in operation. Operate unit and note
suction pressure and container temperature to
see that feeler bulb is properly installed.
CAUTION: Any time the discharge valve
is front seated, disconnect the unit power
source the prevent accidental compressor
start-up.