Bunn CDBCF Airpot - Manual (Page 29)

Page 29
Location:
The tank heater is located inside the tank and
secured to the tank bottom.
Test Procedures:
1. Disconnect the brewer from the power supply.
2. With a voltmeter, check the voltage across the
white or red wire from the terminal block and the
black wire from the control board. Connect the
brewer to the power source. The indication must
be 120 volts ac for two wire 120 volt models or 240
volts ac for three wire 120/240 volt models.
3. Disconnect the brewer from the power source.
If voltage is present as described, proceed to #4
If voltage is not present as described, refer to the
Wiring Diagrams and check wiring harness.
4. Disconnect the black wire and the white wire or red
wire from the tank heater terminals.
5. Check for continuity across the tank heater termi-
nals.
P1855
If continuity is present as described, reconnect the
wires, the tank heater is operating properly.
If continuity is not present as described, replace the
tank heater.
NOTE- If the tank heater remains unable to heat,
remove and inspect heater for cracks in the sheath.
Removal and Replacement:
1. Remove the top cover or top warmer housing and
front access panel as previously described.
2. Disconnect the vent hose from the top of the tank
by pulling the elbow fitting from the grommet in
the top of the tank lid.
3. Drain water from the tank.
4. Disconnect the water supply tube to the dispense
valve from the side of the tank.
5. Disconnect the water supply tube to the solenoid
valve from the bottom of the tank.
6. On brewers with faucet, disconnect the outlet
water line to the faucet from the side of the tank.
7. Disconnect the temperature probe from the top of
the tank by pulling the probe from the grommet in
the top of the tank lid.
8. Disconnect the pink wire from the level probe.
9. Disconnect the green wire from the top of the tank.
10. Disconnect the limit thermostat from the side of
the tank.
11. Disconnect the two white wires from the tank
warmer blanket.
12. Disconnect the black wire and the white or red wire
from the tank heater terminals.
13. Remove the four #8-32 nuts securing the tank to
the mounting brackets and remove the tank as-
sembly.
14. Remove the eight #8-32 nuts securing the tank lid
to the tank.
15. Remove the two hex nuts securing the tank heater
to the bottom of the tank. Remove tank heater with
gaskets and discard.
16. Install new tank heater with gaskets to the bottom
of the tank and secure with two hex nuts.
SERVICE (cont.)
TANK HEATER
FIG. 13 TANK HEATER
29253 091603