Bunn CW APS Operating Guide
Page 21
TANK HEATER
P1127.40
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. With a voltmeter, check the voltage across the
1. Disconnect the brewer from the power supply.
2. With a voltmeter, check the voltage across the
black and white wires on 100 or 120 volt models
or the black and red wires for 120/240 volt mod-
els, 200 volt models and 240 volt models . Con-
nect the brew to the power source. The indication
must be:
a) 120 volts ac for two wire 120 volt 15 and 20
amp models .
b) 240 volts ac for three wire 120/240 volt models.
c) 200 to 240 volts ac for two wire 200 or 240 volt
models.
d) 100 volts ac for two wire 100 volt models.
or the black and red wires for 120/240 volt mod-
els, 200 volt models and 240 volt models . Con-
nect the brew to the power source. The indication
must be:
a) 120 volts ac for two wire 120 volt 15 and 20
amp models .
b) 240 volts ac for three wire 120/240 volt models.
c) 200 to 240 volts ac for two wire 200 or 240 volt
models.
d) 100 volts ac for two wire 100 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
Wiring Diagrams and check wiring harness.
If voltage is not present as described, refer to the
Wiring Diagrams and check wiring harness.
SERVICE (cont.)
10690 062300
FIG. 12 TANK HEATER
4. Disconnect the black wire and the white wire or red
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.
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 heater for cracks in the sheath.
remove and inspect heater for cracks in the sheath.
Removal and Replacement:
1. Disconnect the water supply tube from the fill
1. Disconnect the water supply tube from the fill
basin.
2. Remove the tank inlet fitting securing the fill basin
to the tank lid, remove fill basin and tank inlet
gasket. Set all three parts aside for reassembly.
gasket. Set all three parts aside for reassembly.
3. On brewers with a faucet, shut off water supply to
the brewer and disconnect the inlet and outlet
water lines to the faucet coil assembly.
water lines to the faucet coil assembly.
4. Disconnect the black wire on the limit thermostat
from the tank heater switch. On late model brew-
ers also disconnect the blue wire from the limit
thermostat to the control thermostat.
ers also disconnect the blue wire from the limit
thermostat to the control thermostat.
5. Disconnect the black wire and the white or red wire
from the tank heater terminals.
6. Remove sprayhead and the hex nut securing the
sprayhead tube to the hood. Set aside for reas-
sembly.
sembly.
7. Remove the eight #8-32 nuts securing the tank lid
to the tank.
8. Remove the tank lid with limit thermostat, spray-
head tube, tank heater, coil assembly and control
thermostat w/bracket (early models only).
thermostat w/bracket (early models only).
9
Remove the two hex nuts securing the tank heater
to the tank lid. Remove tank heater with gaskets
and discard.
to the tank lid. Remove tank heater with gaskets
and discard.