Bunn S, Operating & Service Manual

Page: 26 / 44

Page 26
P1598
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 the
wiring diagrams and check the brewer wiring harness.
5. Reconnect the blue wire to terminal 1.
6. Carefully connect a piece of insulated jumper
wire to terminal 4. Keep the other end of this wire
away from any metal surface of the brewer.
7. Check the voltage across terminals 1 & 3 with a
voltmeter. Connect the brewer to the power
source.Turn the "ON/OFF" switch to the "ON"
position The indication must be:
a.) 120 volts ac for three wire 120/208 volt
models and three wire 120/240 volt models after
a delay of approximately 5 seconds.
b.) 200 to 240 volts ac for two wire 200 or 240
volt models after a delay of approximately 5
seconds.
8. Touch the free end of jumper wire to the brewer
housing. The indication must be 0.
9. Move the jumper wire away from the brewer
housing. The indication must again be:
a.) 120 volts ac for three wire 120/208 volt
models and three wire 120/240 volt models after
a delay of approximately 5 seconds.
b.) 200 to 240 volts ac for two wire 200 or
240volt models after a delay of approximately 5
seonds.
10. Disconnect the brewer from the power source
and remove the jumper wire from terminal 4.
Location:
The liquid level probe is located within the tank lid
inside the fill basin. The liquid level board is located
inside the rear inspection panel on the top left of
component mounting bracket.
Test Procedure.
1.
Disconnect the brewer from the power source.
2. Remove the blue wire from terminal 1 and the
pink wire from terminal 4 of the circuit board.
3. Check the voltage across terminals 2 and 3 with
a voltmeter. Connect the brewer to the power
source. Turn the "ON/OFF" switch to the "ON"
position.The indication must be:
a) 120 volts ac for two wire 120 volt models and
three wire 120/240 volt models.
b) 200 to 240 volts ac for two wire 200 volt or 240
volt models.
c) 100 volts ac for two wire 100 volt models.
FIG. 18 LIQUID LEVEL PROBE
& CONTROL BOARD
29251 052500
LIQUID LEVEL CONTROL BOARD (Models STF &
STFA)
SERVICE (cont.)