Tank Heater - Bunn DV Service Manual

SERVICE (cont.)

Tank Heater

Location:
The tank heater is located in the tank lid.
FIG. 16a TANK HEATER
FIG. 16b TANK HEATER
Test Procedure:
1. Disconnect the dispenser from the power source.
2. Check the voltage across the terminals of the tank
heater with a voltmeter. Connect the dispenser to
the power source. The indication must be:
a.) 100 to 120 volts ac for 100 to 120 volt models
or
b.) 200 to 240 volts ac for 200 to 240 volt models
or
c.) 230 volts ac for 230 volt models.
3. Disconnect the dispenser from the power source.
If voltage is present as described, proceed to #4.
If voltage is not present as described, replace the tank
heater.
4. Remove the tank heater from the tank lid and in-
spect it for cracks in the sheath.
If the sheath shows no sign of damage, proceed to #5.
If the sheath is damaged, replace the tank heater.
5. Check for continuity across the tank heater termi-
nals.
If continuity is present as described, reinstall the tank
heater. The tank heater is operating properly.
If continuity is not present as described, replace the
tank heater.
Removal and Replacement:
H 5
1. Remove the wires to the tank heater.
P4093
2. Remove the 8-32 nuts from the tank heater fl ange.
3. Remove the tank heater.
4. Inspect the tank heater gasket and replace if neces-
sary.
5. Securely install the new tank heater. Be certain of
a watertight seal.
6. Reconnect the wires, FIG. 10.
BLU to Control
Board Relay
H 10
P1993
1800W-120V
4000W-240V
4000W-208V
6000W-240V
6000W-208V
16
FIG. 16c TANK HEATER WIRING
HEATER
TERMINAL TO SHEATH - INFINITE (OPEN)
BLK to Limit
Thermostat
P1780
RESISTANCE
07.44 - 08.67
13.43 - 15.51
10.09 - 11.99
08.85 - 10.23
06.67 - 07.70
42311 071310