Thermo King SB-190 30, Manual

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Refrigeration Service Operations (Rev. 12/03)
76
7. Line up the passageways in the cap and body. Failure to
line up the holes will result in improper operation of the
valve.
8. Install the bolts and tighten in rotating sequence.
9. Install the pilot line and pressurize the system with
refrigerant to check for leaks.
10. If there are no leaks, evacuate the system and recharge
with the proper refrigerant.
11. Run the unit to check for proper three-way valve
operation.
THREE-WAY VALVE CONDENSER
PRESSURE BYPASS CHECK VALVE
REPAIR
Removal
1. Recover the refrigerant charge.
2. Unscrew the condenser pressure bypass check valve
cap from the three-way valve.
3. Remove the snap ring.
4. Unscrew the check valve stem by using a screwdriver
in the slot provided.
NOTE: The spring and valve are held in by the stem.
While removing the stem, use care so the spring and
valve are not lost.
5. Remove the spring and Teflon check valve.
6. Inspect the check valve seat in the three-way valve.
7. If replacement parts are needed, a P/N 60-163 kit must
be used which includes the Teflon check valve, spring,
O-ring, valve stem and snap ring.
Installation
1. Coat the O-ring with compressor oil and install it on the
check valve stem.
2. Insert the spring into the hole in the check valve stem
and then install the Teflon check valve on the other end
of the spring with the hole in the valve towards the
spring.
3. Coat the entire assembly with compressor oil and
install the assembly into the Teflon check valve seat in
the three-way valve.
CAUTION: The Teflon check valve must be
inserted with the flat side against the valve seat
to ensure proper sealing.
4. Screw the check valve stem into the three-way valve
until the snap ring can be installed.
5. Install the snap ring.
6. Unscrew (back seat) the check valve stem against the
snap ring.
NOTE: The valve stem must be back seated during
normal unit operation.
7. Coat sealing area in the cap with compressor oil, install
and tighten the cap on the three-way valve.
1. Teflon Check Valve 4. Stem
2. Snap Ring 5. O-ring
3. Cap 6. Spring
Teflon Check Valve Assembly
AEA715