Carrier 69NT40-561-300, Operation And Service Manual

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T-365 7–26
19.Weigh the proper refrigerant charge into the unit as per the units operation and service manual and perform
a leak check of the system.
20.Replace the guard under the control box.
21.If changed under the units warranty, tag part with unit information and cause of failure.
22.If possible collect unit data download for future failure analysis.
7.21 DIGITAL UNLOADER VALVE
7.21.1 Digital Unloader Replacement
1. Power unit off and lock out / tag out to prevent inadvertent power up. Follow the regional lock out tag out pro-
cedure for electrical system.
2. Remove 8 bolts from guard under control box and remove guard.
3. Remove the digital unloader valve coil (DUV) and place a magnet tool on the valve to open it. If a magnet is
not available perform the Jumper procedure:
a. Remove all 4 controller fuses (F1, F2, F3a, F3b).
b. Remove the wire from the KA6 connector on the front of the controller.
c. Disconnect the X1 wire from the 24VAC side of transformer (black wire) and locate it away for the trans-
former.
d. Jumper the black transformer wire to the KA6 wire removed from the connector.
e. Connect power to unit and turn circuit breaker on (DUV coil is now energized).
4. Using a refrigerant recovery machine, remove the refrigerant from the unit. Refer to the Operation and Ser-
vice manual of the selected recovery machine for proper procedures.
5. On completion of the recovery, if the jumper procedure was used turn the circuit breaker off and disconnect
the power. Follow the regional lock out tag out procedure for electrical system.
6. Remove insulation from suction line to prevent damage while brazing.
7. If coil was not removed in step three, remove the top screw from DUV coil and remove coil. Position coil
away from valve body.
8. Cut the cable tie for the compressor dome temperature sensor and move wiring to one side.
9. Using a tubing cutter, cut the lines marked at locations in Figure 7.19 .
Figure 7.19 DUV Installation
Cut
DLV
DUV
Wet Rag All Areas
Prior to Brazing
SSV
Cut above Bell. Un
ï
braze, sliding the tubing
out of the bell on the service valve.