Bunn CWTF TWIN-APS Coffeemaker User Manual


 
Page 19
SERVICE (cont.)
SOLENOID VALVES
Location:
The solenoid valves are located inside the trunk on
the lower center part of the component brackets.
Test Procedures:
1. Disconnect the brewer from the power source.
2. Disconnect the white and black wires from the
solenoid valve. Connect the brewer to the power
source. With the "ON/OFF" switch in the "ON" upper
position press the start switch.
3. With a voltmeter, check the voltage across the
white and black wires. The indication must be:
a) 120 volts ac for three wire 120/240 volt models.
b) 200 volts ac for two wire 200 volt models.
c) 240 volts ac fro two wire 240 volt models.
d) 230 volts ac for three wire three phase 230 volt
models.
4. Disconnect the brewer from the power source
If voltage is present as described, proceed to #5
If voltage is not present as described, refer to
Wiring
Diagrams
and check brewer wiring harness.
5. Check for continuity across the solenoid valve coil
terminals.
If continuity is present as described, reconnect the
white and black wire from the timer.
P2197
FIG. 10 SOLENOID VALVES
10737 100801
FIG. 11 SOLENOID VALVE TERMINALS
WHI/BLU from Timer
WHI/GRN from Timer
P1132
6. Check the solenoid valve for coil action. Connect
the brewer to the power source. With "ON/OFF"
switch in the "ON" upper position press start switch
and listen carefully in the vicinity of the solenoid
valve for a "clicking" sound as the coil magnet
attracts.
7. Disconnect the brewer from the power source.
If the sound is heard as described and water will not
pass through the solenoid valve, there may be a
blockage in the water line before the solenoid valve or
the solenoid valve may require inspection for wear and
removal of waterborne particles.
If the sound is not heard as described, replace the
solenoid valve.
Removal and Replacement:
1. Remove the white and black from the solenoid
valve.
2. Turn off the water supply to the brewer.
3. Disconnect the water lines to and from the sole-
noid valve.
4. Remove the two #8-32 screws securing the sole-
noid mounting bracket to the component bracket.
Remove solenoid bracket and solenoid valve as an
assembly.
5. Remove the two #10-32 screws and lockwashers
securing the solenoid valve to the solenoid bracket.
6. Using two #10-32 screws and lockwashers install
new solenoid valve on solenoid mounting bracket.
7. Using two #8-32 screws install solenoid valve and
bracket to the component bracket.
8. Securely fasten the water lines to and from the
solenoid valve.
9. Refer to Fig. 11 when reconnecting the wires.