Level Control Board And Level Probe - Bunn Single TF Operating & Service Manual

SERVICE (cont.)

LEVEL CONTROL BOARD AND LEVEL PROBE

(Electro/mechanical only)
22978.0000
Location:
The level control board is located inside the front
in center of the brewer on the component bracket. The
level probe is located inside the hood on the center rear
of the tank lid.
Test Procedure:
1. Disconnect the brewer from the power source.
2. Remove the violet wire from terminal 1 & pink wire
from terminal 4 of the circuit board.
3. Check the voltage across terminals 2 & 3 with a
voltmeter. Connect the brewer to the power source.
The indication must be:
a.) 120 volts ac for two wire 120 volt models, 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.
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.
J1
J2
SET
LOC
K
5. Reconnect the violet 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.
The indication must be:
a.)120 volts ac for two wire 120 volt models, three
wire 120/208 volt models and three wire 120/240
volt models after a delay of approximately 1 sec-
ond.
b.)200 to 240 volts ac for two wire 200 or 240 volt
models after a delay of approximately 1 second.
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 two wire 120 volt models, three
wire 120/208 volt models and three wire 120/240
volt models after a delay of approximately 1 sec-
ond.
b.) 200 to 240 volts ac for two wire 200 or 240 volt
models after a delay of approximately 1 second.
10. Disconnect the brewer from the power source and
remove the jumper wire from terminal 4.
P999
If voltage is present as described, the level control
board is operating properly, proceed to #11.
If voltage is not present as described, replace the level
control board.
11. Reconnect the pink wire to terminal 4.
12. Gently pull the probe out of the tank lid and inspect
for corrosion. Replace it if necessary.
13. Place the probe so that neither end is in contact
with any metal surface of the brewer.
14. Check the voltage across terminals 1 & 3 with a
voltmeter.Connect the brewer to the power source.
The indication must be:
a.) 120 volts ac for two wire 120 volt models,
three wire 120/208 volt models and three wire
120/240 volt models after a delay of approximately
1 second.
b.) 200 to 240 volts ac for two wire 200 or 240 volt
models after a delay of approximately 1 second.
15. Move the probe's flat end to the brewer housing.
The indication must be 0.
16. Move the probe's flat end away from the brewer
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