Tank Heater - Bunn VLPF Operating & Service Manual

SERVICE (cont.)

TANK HEATER

PN : 658
FIG. 24 TANK HEATER
Location:
The tank heater is located on the tank lid.
Test Procedure:
1. Disconnect the brewer from the power source and
remove both wires from the tank heater.
2. With a voltmeter, check the voltage across the
black and white wires removed from the tank
heater when the control thermostat is turned "ON"
(fully clockwise). 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
Wiring Diagram and check the brewer wiring harness.
4. Check for continuity across the terminals of the
tank heater.
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 the heater for cracks in the sheath.
Removal and Replacement:
1. Remove the white wire from the tank heater ter-
minal and the blue wire from the limit thermostat
terminals.
2. Gently pull the liquid level probe and thermostat
tube with grommet out of the tank lid.
3. Disconnect the 1/4" flare fitting on the tank lid in-
let fitting.
4. Remove the sprayhead and sprayhead nut from
the panel on the bottom of the hood.
5. Disconnect the airvent tube from the fitting above
the sprayhead panel.
6. Loosen the eight #8-32 nuts on the tank lid and
remove the tank lid.
7. Remove the two nuts from the tank heater fittings.
8. Remove the tank heater.
9. Install the new tank heater with new sealing wash-
ers on the underside of the tank lid.
10. Securely tighten the nuts to be certain of a water-
P1983
tight seal.
11. Reinstall tank lid and secure with eight #8-32 nuts.
12. Reinstall the sprayhead tube nut and sprayhead.
13. Reinstall the liquid level probe and thermostat into
the tank lid.
14. Securely fasten the 1/4" flare fitting to the tank lid
inlet fitting.
15. Refer to FIG. 25 when reconnecting the wires.
Page 27
BLK to limit thermostat
WHI to Cordset
FIG. 25 TANK HEATER TERMINALS
P1990.70
10179 060100