Carrier TRANSICOLD 69NT40-489, Операция и обслуживание

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4-8
o. Install mounting bolts in service valves and torque to
a value of 2.77 to 4.15 mkg (20-30 ft/lb).
p. Install a new filter-drier. (Refer to section 4.12)
q. Evacuate and Dehydrate per section 4.5
Add refrigerant to system per section 4.6.2
r. Start unit and check refrigerant charge. (Refer to
section 4.6.1.)
s. Check moisture-liquid indicator for wetness. Change
filter-drier if necessary. (Refer to sections 4.11 and 4.12)
t. Check compressor oil level per section 4.10. Add oil
if necessary.
u. Fully backseat (open) both suction and discharge
service valves.
v. Remove gauges.
4.8 COMPRESSOR DISASSEMBLY
WARNING
Before disassembly of the compressor make sure
to relieve the internal pressure very carefully by
slightly loosening the bolts on both service valve
flanges/blank valve pads, then lightly tap the
sides of the valve flanges/pads with a hammer to
break the seal.
CAUTION
Removing the press fit stator in the field is not
recommended. The rotor and stator are a
matched pair and should not be separated.
When disassembling compressor, matchmark parts
so they may be replaced in their same relative positions.
(See Figure 4-5 for an illustration of the compressor.)
Refer to Table 4-4 and Table 4-5 for compressor wear
limits and bolt torque values.
a. Place the compressor in a position where it will be
convenient to drain the oil. Remove the oil plug on oil
pump inlet passage (See Figure 4-9 for location) to vent
the crankcase. Loosen the drain plug (See Figure 4-5) in
bottom plate and allow the oil to drain out slowly.
Remove the plug slowly to relieve any crankcase
pressure. A plug in the bottom center of the crankcase
may also be removed for draining the motor end more
quickly. (Some units do not have this plug.)
b. Remove cylinder head capscrews. If the cylinder
head is stuck, tap the center of the cylinder head with a
wooden or lead mallet. DO NOT STRIKE THE SIDE
OF THE CYLINDER HEAD! Be careful not to drop the
head or damage the gasket sealing surface. (See
Figure 4-5 and Figure 4-7.) Remove cylinder head
gasket.
c. Free the valve plate from the cylinder deck by using
the outside discharge valve hold down capscrew as a jack
screw through the tapped hole of the valve plate after the
valve stops and valves have been removed. Remove the
valve plate gasket. (See Figure 4-7.)
1 2 3 4 5 7
6
1. Cylinder Head Gasket
2. Discharge Valve Screw and Lockwasher
3. Discharge Valve Stop
4. Discharge Valve
5. Valve Plate
6. Valve Plate Assembly
7. Valve Plate Gasket
Jack here
Figure 4-7. Exploded View of Valve Plate
d. Turn the compressor over on its side and remove the
bottom plate. Match mark each connecting rod cap and
connecting rod for correct reassembly. Remove the bolts
and connecting rod caps (See Figure 4-8). Push the
piston rods up as far as they will go without having the
piston rings extend above the cylinders.
1
2
3
4
5
1. Oil Pressure Relief Valve
2. Oil Return Check Valve
3. Oil Suction Tube
4. Capscrew
5. Connecting Rod and Cap Assembly
Figure 4-8. Bottom Plate Removed
CAUTION
The copper tube which connects to the oil suction
strainer extends out the bottom with the bottom
plate removed. Take precautions to avoid
bending or breaking it while changing crankcase
positions.
e. If necessary, remove the oil return check valve.
Inspect it for check valve operation (flow in one direction
only). Replace assembly if its check valve operation is
impaired. (See Figure 4-8.)
f. There are two types of oil pumps; gear and low
profile gear. See Figure 4-6 to identify which oil pump is
used.
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