Thermo King T-1080S, Руководство по обслуживанию

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Refrigeration Service Procedures
146
Installation of Service Kit
NOTE: Do not connect the ETV harness or ETV
to main wire harness and turn the unit on before
the stepper motor and piston assembly is
installed in the valve body. The controller is
programmed to close the ETV when the unit is
turned on. If the unit is turned on with the ETV
harness connected to main wire harness, the
controller will attempt to close the ETV. This will
cause the piston to be turned (screwed) off the
threaded shaft of the stepper motor because the
valve body is not present to stop it. Further
disassembly is required to reassemble the piston
and stepper motor. See “Reassembly of Piston
and Stepper Motor on Old Style ETV”.
1. The new stepper motor and piston assembly is
supplied with the piston in the open position.
In the open position the bottom edge of the
piston is 0.3 to 0.7 in. (8 to 18 mm) from the
bottom edge of the brass nut/piston housing.
The piston retracts to open and extends to
close.
2. Old Style ETV Only:
a. Lubricate the piston and threads on the
new stepper motor and piston assembly
with refrigeration oil.
b. Screw the new stepper motor and piston
assembly into the valve body.
c. Torque the nut to approximately 118 ft-lb
(160 N•m). Hold the valve body with
backup wrench to prevent damage to the
refrigeration tubing.
3. New Style ETV Only:
a. Lubricate the O-rings with refrigeration
oil. Place one on the stepper motor and
piston assembly and place the other in the
valve body.
b. Place stepper motor and piston assembly
into the valve body and make sure the
arrowhead marks on them are aligned as
shown below.
1. Bottom Edge of Brass Nut/Piston Housing
2. Bottom Edge of Piston
Figure 231: Stepper Motor and Piston Assembly
with Piston in Fully Open Position
ARA2501
1
2
1
2
0.3 in.
(8 mm)
1. Install O-Ring on Stepper
Motor and Piston Assembly
Figure 232: Install O-Ring
1. Install O-Ring in Valve Body
Figure 233: Install O-Ring
ARA2502
1
ARA2503
2