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Refrigeration Service Operations
131
Installation
NOTE: Three-way valve kit is used to repair
three-way valves (see Tool Catalog).
After cleaning and inspecting all parts, reassemble
the valve. Clean solder off the condenser line and
condenser head with sandpaper and tubing brush.
1. Install the screen into the bottom cap.
2. Install new stem into the center section.
3. Install new gaskets on both sides of the valve
body. Dip gaskets in compressor oil (use same
type of oil that is used in the system) before
installing.
4. Install a new o-ring on the piston, then place
the Teflon seal over the o-ring.
5. Install the piston on the stem and attach with
spring clip.
NOTE: The Teflon seal will stretch when it is
installed. To prevent this from becoming
permanent (and possibly malfunction), the
top cap must be installed immediately.
6. Install the spring and top cap.
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 bolts and tighten in rotating sequence.
9. Solder condenser line to the condenser inlet.
10. Install pilot solenoid line and pressurize
system with refrigerant to check for leaks.
11. If there are no leaks, evacuate the system and
recharge with refrigerant.
12. Run the unit to check for proper three-way
valve operation.
Compressors Shipped with
R-134a
X426 Thermo King compressors are charged with
Polyol Ester oil (POE) (TK No. 203-413). All
gauge fittings are 1/4 inch fittings.
Because Polyol Ester has an affinity for moisture,
it must be kept in capped containers. In addition,
it should be added as the last step in system repair.
Rubber gloves are recommended when handling
Polyol Ester because it may cause skin irritation.
Equipment Recommendations
For Use With R-404A
Vacuum Pumps
When evacuating, a two stage three or five CFM
pump is recommended. It is also recommended
that dry nitrogen be used first. Ideally, a new
vacuum pump should be used and dedicated for
use with R-404A systems because residual
refrigerants may remain in used vacuum pumps.
Pumps used with other Thermo King refrigerants
may be used but extreme care should be taken to
prevent contamination of R-404A systems with
other refrigerants.
An oil filter TK P/N 66-7800 is added to the
vacuum pump.
The Thermo King Evacuation Station is
recommended. This station is available from
service parts under part number 204-725. See
Truck and Trailer Service Bulletin T&T 061 for
additional details.
Use only recommended vacuum pump oils and
change oil after every major evacuation. Vacuum
pump oils are highly refined and the use of
contaminated oils will prevent the desired vacuum
CAUTION: Polyol Ester (POE) is the only
oil for use with Thermo King units using
R-134a and R-404A. It should not be
added to standard Thermo King units, nor
should the standard or synthetic oil be
added to system containing R-134a and
R-404A. Combining the two oils could
result in damage to the system.
Summary of Contents for 914970
Page 3: ...3...
Page 10: ...Table of Contents 10...
Page 40: ...Operating Instructions 40...
Page 82: ...Electronic Controls 82...
Page 92: ...Electrical Maintenance 92...
Page 124: ...Refrigeration Maintenance 124...
Page 140: ...Hilliard Clutch Maintenance 140...
Page 160: ...Refrigeration Diagrams 160...
Page 163: ...Index 163 W wiring 85 wiring diagrams 165...
Page 164: ...Index 164...
Page 166: ...Wiring and Schematic Diagrams Index 166...
Page 167: ...167 Cab Control RD Wiring Diagram...
Page 168: ...168 RD w o Thermostat Cab Control Schematic...
Page 169: ...169 RD Cab Box Wiring Diagram...
Page 170: ...170 RD Cab Control w Thermostat Schematic Diagram...
Page 171: ...171 RD 50 STD 3 Phase Wiring Diagram Page 1 of 2...
Page 172: ...172 RD 50 STD 3 Phase Wiring Diagram Page 2 of 2...
Page 173: ...173 RD 50 STD 3 Phase Schematic Diagram Page 1 of 2...
Page 174: ...174 RD 50 STD 3 Phase Schematic Diagram Page 2 of 2...
Page 175: ...175 RD 30 STD Wiring Diagram Page 1 of 2...
Page 176: ...176 RD 30 STD Wiring Diagram Page 2 of 2...
Page 177: ...177 RD 30 STD Schematic Diagram Page 1 of 2...
Page 178: ...178 RD 30 STD Schematic Diagram Page 2 of 2...
Page 179: ...179 RD 30 C S Wiring Diagram Page 1 of 2...
Page 180: ...180 RD 30 C S Wiring Diagram Page 2 of 2...
Page 181: ...181 RD w CYCLE SENTRY Schematic Diagram Page 1 of 2...
Page 182: ...182 RD w CYCLE SENTRY Schematic Diagram Page 2 of 2...
Page 183: ...183 RD 50 C S 3 Phase Wiring Diagram Page 1 of 2...
Page 184: ...184 RD 50 C S 3 Phase Wiring Diagram Page 2 of 2...
Page 185: ...185 RD w CYCLE SENTRY Schematic Diagram Page 1 of 2...
Page 186: ...186 RD w CYCLE SENTRY Schematic Diagram Page 2 of 2...