SERVICE (cont.)

TANK HEATER

FIG. 13-1 TANK HEATER

Location:

The tank heater is located inside the tank and secured to the tank lid.

Test Procedures:

1.Disconnect the brewer from the power supply.

2.Turn on thermostat. Check the voltage across the black and white wires on 120 volt models or the black and red wires for 200 volt models and 230 volt models with a voltmeter. Connect the brewer to the power source. The indication must be:

a)120 volts ac for two wire 120 volt 20 amp models .

b)200 to 230 volts ac for two wire 200 or 230 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 Wir- ing Diagrams and check wiring harness.

4.Disconnect the wires from the tank heater termi- nals.

5.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.

HEATER

RESISTANCE

1680W-120V

7.9

- 9.2

1680W-100V

5.5

-6.4

1680W-230V

29.0

-33.7

TERMINAL TO SHEATH - INFINITE (OPEN)

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.

Removal and Replacement:

1.Disconnect the brewer from the power supply.

2.Disconnect the water supply from the brewer.

3.Disconnect the wires from the limit thermostat.

4.Disconnect the wires from the tank heater termi- nals.

5.Remove sprayhead and the hex nut securing the sprayhead tube to the hood. Set aside for reas- sembly.

6.Remove the six #10 screws securing the tank lid to the tank.

7.Remove the tank lid with limit thermostat, spray- head tube and tank heater.

8Remove the two hex nuts securing the tank heater to the tank lid. Remove tank heater with gaskets

and discard.

9.Install new tank heater with gaskets on the tank lid and secure with two hex nuts.

10.Install tank lid with limit thermostat, sprayhead tube and tank heater using six #10 screws.

11.Secure sprayhead tube to hood using hex nut removed in step 4.

12.Install sprayhead.

15.Reconnect the wires to the limit thermostat and tank heater.

16.Reconnect the water and power supply.

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Image 13
Bunn 41722.0000A Tank Heater, Disconnect the brewer from the power supply, 1680W-120V 1680W-100V 1680W-230V 29.0 33.7