Thermo King T-1080S, Руководство по обслуживанию

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Refrigeration Service Procedures
145
4. Old Style ETV - Unscrew the large nut that
attaches the stepper motor and piston
assembly to the valve body. The torque on the
nut is approximately 118 ft-lb (160 N•m).
Hold the valve body with backup wrench to
prevent damage to the refrigeration tubing.
New Style ETV - Remove the four screws that
attach the stepper motor to the valve body.
5. If the complete ETV assembly is being
replaced, remove the ETV mounting hardware
and unsolder and remove the valve body. It
may be necessary to unsolder other tubes near
the valve body to obtain enough clearance to
remove the valve body. Note the position of
the valve body so the new one will be placed
in the same position.
WARNING: If the ETV is stuck in the
closed position, much of the refrigerant
charge may be trapped in the evaporator.
If you hear refrigerant begin to flow
through the valve when the stepper motor
and piston assembly are loosened,
unscrew the Old Style ETV stepper motor
and piston assembly no more than four
turns, or unscrew the four screws on the
New Style ETV stepper motor no more
than four turns each, and check the
suction (low side) pressure on the gauge
manifold. If the suction pressure has
increased from the pressure to which it
was equalized after the low side pump
down, refrigerant is trapped and must be
recovered. Screw the stepper motor and
piston assembly back into the valve body.
Attach a refrigerant recovery device to the
service port on the receiver tank outlet
valve. Midseat the receiver tank outlet
valve, and recover the refrigerant charge.
The stepper motor and piston assembly
may then be removed.
CAUTION: Old Style ETV - Unscrew the
large nut. Do not unscrew the small hex
on the stepper motor.
1. Unscrew Large Nut
2. Backup Wrench
Figure 229: Removing Old Style Stepper Motor
1. Remove Four Screws
Figure 230: Removing New Style Stepper Motor
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ARA2500
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