Bunn cdbcf 15 User Guide

Page 20

The tank heaters are located inside the tank and secured 
to the tank bottom.

1.  With a voltmeter, check voltage across the white 

wire (120V Models) or red wire (120/208-240V 
Models) from the terminal block and black wire 
from the control board. Connect brewer to the 
power source. The indication must be 120 volts 
ac for two wire 120 volt models or 208-240 volts 
ac for three wire 120/208-240 volt models (during 
a heating cycle).

2.  Disconnect the brewer from the power source.

If voltage is present as described, proceed to #3.
If voltage is not present as described, refer to the 
Wiring Diagrams and check wiring harness. If harness 
checks ok, replace control board.

3.   Disconnect the wires from the tank heater termi-

nals.

4.    Check resistance value across tank heater terminals 

and compare to chart.

If resistance is present as described, reconnect the 
wires, the tank heater is ok.
If resistance is not present as described, replace the 
tank heater.

NOTE- If any resistance is read between sheath and 
either terminal, remove and inspect heater for cracks 
in the sheath.

1425W 

Small 

Dia.

2268W 

Large 

Dia.

1425W-120V 

  10.10 

3500W-240V 

  16.46 

1850W-240V 

  31.14 

3500W-200V 

  11.43 

3000W-240V 

  19.20 

2268W-240V 

   

 

6.35 

HEATER

1.  Remove the top cover or top warmer housing and 

front access panel as previously described.

2.  Drain water from the tank.
3.  Disconnect all the hoses from the tank.
4.  Disconnect the temperature probe from the top of 

the tank by pulling the probe from the grommet in 
the top of the tank lid.

5.  Remove both level probes from their grommets.
6.  Disconnect the green wire from the top of the 

tank.

7.  Disconnect the limit thermostat from the side of 

the tank.

8.  Disconnect the two white wires from the tank 

warmer blanket.

9. Disconnect the wires from tank heater terminals.
10. Remove the four #8-32 nuts securing the tank to 

the mounting brackets and remove the tank as-
sembly.

11. Remove the eight #8-32 nuts securing the tank lid 

to the tank.

12. Remove the two hex nuts securing the tank heater 

to the bottom of the tank. Remove tank heater with 
gaskets and discard.

13. Install new tank heater(s) with gaskets to the bot-

tom of the tank and secure with two hex nuts.

14. Install tank assembly onto mounting brackets and 

secure in place with four #8-32 nuts.

15.  Install tank lid and secure in place with eight #8-32 

nuts.

16. Connect the two white wires of the tank warmer 

blanket.

39132 041708

RESISTANCE

TERMINAL TO SHEATH - INFINITE (OPEN)