Bunn TU3Q - Manual (Page 15)

Page 15
SERVICE (cont.)
BREW SOLENOID VALVE
FIG. 2 BREW SOLENOID VALVE P2087.40
Location:
Viewing the brewer from the top, the brew sole-
noid valve is mounted on the right side of the brewer.
Test Procedures:
1. Disconnect the brewer from the power source.
2. Disconnect the white/violet and white/green wires
from the solenoid valve. With the ON/OFF switch
in the "ON" position ("UNSWEET" or "SWEET" po-
sition for brewers with sweetener option), press
the start switch.
3. With a voltmeter, check the voltage across the
white/violet and white/green wires. Connect the
brewer to the power source. The indication must
be:
a) 120 volts ac for two wire 120 volt models.
b) 230 volts ac for two wire 230 volt models.
c) 100 volts ac for two wire 100 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/violet from the brew timer and white/green wire
from the brew timer.
If continuity is not present as described, replace the
solenoid valve.
6. Check the solenoid valve for coil action. Connect
the brewer to the power source. With ON/OFF
switch in the "ON" position ("UNSWEET" position
for brewers with sweetener option), 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 block-
age 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 all wires from 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 keps nuts holding the
mounting bracket to the hood.
5. Lift out the bracket.
6. Remove the two #10-32 slotted-head screws hold-
ing the solenoid valve to the mounting bracket.
7. Securely install the new solenoid valve to the
mounting bracket.
8. Attach the mounting bracket to the hood.
9. Securely fasten the water lines to and from the
solenoid valve.
10. Refer to the Fig. 3 when reconnecting the wires.
FIG. 3 SOLENOID VALVE TERMINALS
P2843
10288 031604
WHI/GRN to
Brew Timer TL4
WHI/VIO to
Brew Timer TL1
BREW SOLENOID