Thermo King SB-210, Manual

Page: 117 / 159

Refrigeration Service Operations
117
2. Clean the exterior surface of the valve.
3. Remove the line from the three-way valve to
the pilot solenoid.
4. Loosen the four 1/4 in. Allen head screws (DO
NOT REMOVE OR CAP MAY POP OFF);
use tool P/N 204-424 to break the gasket at
each side of the center section.
Figure 101: Gasket Tool P/N 204-424
5. Remove the four bolts from the valve.
6. Remove the end cap and spring.
7. Remove the spring clip which secures the
stem to the piston. Slide piston off the stem.
8. Remove the seat and stem assembly.
9. Inspect the following parts for wear or
damage:
a. Bottom cap, sealing and support area.
b. Seat, sealing surface.
c. End cap, sealing and support surface.
The following parts will be discarded:
a. Stem assembly.
b. All gaskets.
c. Piston seal.
10. Remove the screen. If any particles drop from
the screen into the discharge line, the
discharge line must be removed at the
compressor.
NOTE: The valve body cannot be
reconditioned. Seat positions change and
improper sealing will result.
End Cap Checks
All end caps, even new ones, should be checked
as follows. See Service Bulletin T&T 260 for
more information.
Check Valve Bleed Hole Diameter
1. Remove the condenser pressure bypass check
valve snap ring, stem, spring, and piston from
the end cap.
2. Use a number 43 (0.089 in. [2.26 mm]) drill
bit to check the size of the hole from the end
cap gasket face to the check valve piston bore
as shown.
3. If the drill does not go all the way into the
bore, drill the hole completely through.
CAUTION: Do not force the tool into the
brass or against the bolts.
AGA1069
1. Seal Groove in Piston
2. Connecting Notch in Piston
3. Internal Spring in Seal
4. Connecting Groove in Stem
5. Retaining Clip
Figure 102: Piston and Stem Parts
2
5
4
3
1
AGA1066