Dispense Valve - Bunn Dual Operating & Service Manual

SERVICE (cont.)

DISPENSE VALVE

FIG. 9 DISPENSE VALVE
Location:
Dispense valves are located inside the hood in the
center of each sprayhead panel.
Test Procedures:
1. Disconnect the brewer from the power source.
2. Disconnect the wires from the right dispense valve
and check the voltage across the white/violet wire
and white/green wire. Connect brewer to the power
source. Place the "ON/OFF" switch in the "ON"
position, press and release the start switch. The
indication must be:
a.) 120 volts ac for three wire 120/208 volt models
and three wire 120/240 volt models.
b.) 200 to 240 volts ac for two wire 200 or 240 volt
models.
3. Disconnect brewer from the power source.
4. Disconnect the wires from the left dispense valve
and check voltage across the white/red wire and
the white/brown wire. Connect the brewer to the
power source. Place the "ON/OFF" switch in the
"ON" position and press and release the start
switch. The indication must be:
a.) 120 volts ac for three wire 120/208 volt models
and three wire 120/240 volt models.
b.) 200 to 240 volts ac for two wire 200 or 240 volt
models.
5. Disconnect brewer from power source.
If voltage is present as described in steps 2 & 4
proceed to #6.
If voltage is not present as described, refer to the
Wiring Diagrams and check brewer wiring harness.
ga l
1⁄2
l 1
1 ga
l
ga
1⁄2
Y
A D
R E
O R
C T
LE
S E
M E R
A R
/ W
O N
A R T
S T
l
ga
1 1⁄2
l
1 ga
l
ga
1⁄2
A R T
S T
M E R
A R
/ W
O N
O R
C T
S E LE
Y
A D
R E
P796
6. Check for continuity across the dispense valve coil
terminals.
If continuity is present as described, reconnect the
wires to the dispense valve and proceed to #7
If continuity is not present as described, replace the
dispense valve.
7. Check the dispense valve for coil action. Connect
the brewer to power source. Place the ON/OFF"
switch in the "ON" position, press and release the
start switch. Listen carefully in the vicinity of the
dispense valve for a "clicking" sound as the coil
magnet attracts and repels the plunger.
8. Disconnect the brewer from the power source.
If the sound is heard as described, there may be a
blockage in the dispense valve or the water line to the
dispense valve. Remove the dispense valve and in-
spect for wear, and remove waterborne particles.
If the sound is not heard as described, replace the
dispense valve.
Removal and Replacement:
1. Disconnect wires and water tubes from dispense
valve.
2. Drain enough water from the tank so the dispense
valves are above the water line.
3. Remove dispense valve from the sprayhead panel.
4. Install new dispense valve.
5. Reconnect the water lines and the wires to the
dispense valve.
6. Refer to Fig. 10 when reconnecting wires.
WHI/RED to Left Timer TL1
WHI/RED to Left Brew Selector Switch
WHI/RED to Left ON/OFF Switch
WHI/BRN to Left Timer TL4
WHI/GRN to Left By-Pass Valve
FIG. 10 DISPENSE VALVE TERMINALS
Page 22
WHI/VIO to Right Timer TL1
WHI/VIO to Right ON/OFF Switch
WHI/RED to Right Brew Selector Switch
WHI/GRN to Right Timer TL4
WHI/GRN to Right By-Pass Valve
RIGHT
LEFT
P782
27040 032201