Bunn TWF-EZ - Manual (Page 22)

Page 22
FIG. 14 TANK HEATER
Location:
The tank heater is located inside the tank and se-
cured to the tank lid.
Test Procedures:
1. Disconnect the brewer from the power supply.
2. With a voltmeter, check the voltage across the
black and white wires. Connect the brewer to the
power source. The indication must be 120 volts
ac.
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 Diagram and check wiring harness.
4. Disconnect the black wire and the white wire from
the tank heater terminals.
5. Check for continuity across the tank heater termi-
nals.
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, re-
move and inspect heater for cracks in the sheath.
Removal and Replacement:
1. Disconnect the black wire and white wire from the
tank heater terminals.
P1960.60
SERVICE (cont.)
TANK HEATER
2. Remove the temperature probe and grommet from
the tank lid.
3. Disconnect and remove the faucet tube.
4. Remove sprayhead and the hex nut securing the
sprayhead tube to the hood. Set aside for reas-
sembly.
5. Disconnect and remove the water inlet tube.
6. Disconnect vent tube.
7. Remove the eight #8-32 nuts securing the tank
lid and the green grounding wire to the tank.
8. Remove the tank lid with limit thermostat, spray-
head tube, tank heater, faucet coil and vent tube.
9. Remove the two hex nuts securing the tank heater
to the tank lid. Remove tank heater with gaskets
and discard.
10. Install new tank heater with gaskets on the tank
lid and secure with two hex nuts.
11. Install tank lid with limit thermostat, sprayhead
tube, tank heater, faucet coil and vent tube. Install
green grounding wire to tank stud and secure with
eight #8-32 nuts.
12. Secure sprayhead tube to hood using a hex nut.
13. Install sprayhead.
14. Connect vent tube to fitting.
15. Install the faucet tube.
16. Install water inlet tube.
17. Install the temperature probe and grommet to the
tank lid.
18. Reconnect the wires to the limit thermostat and
tank heater. See limit thermostat section when
reconnecting wires.
19. Refer to Fig.15 when reconnecting the tank heater
wires.
FIG. 15 TANK HEATER TERMINALS P1369