Bunn CWTF-APS-MV Manuales De Servicio
Page 21
TANK HEATERS
Location:
The tank heaters are 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 tank heater voltage
1. Disconnect the brewer from the power supply.
2. With a voltmeter, check the tank heater voltage
across blue and white wires on 120 volt 15 amp
version, black and white wires on 120 volt 20 amp
version or black and blue wires on 120/208 volt or
120/240 volt version at the tank heater terminal
block. Connect the brewer to the power source.
The indication must be:
a) 120 volts ac for two wire 120 volt 15 and 20 amp
models.
b) 208 volts ac for three wire 120/208 volt models.
c) 240 volts ac for three wire 120/240 volt models.
version, black and white wires on 120 volt 20 amp
version or black and blue wires on 120/208 volt or
120/240 volt version at the tank heater terminal
block. Connect the brewer to the power source.
The indication must be:
a) 120 volts ac for two wire 120 volt 15 and 20 amp
models.
b) 208 volts ac for three wire 120/208 volt models.
c) 240 volts ac for three wire 120/240 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.
4. Disconnect the black, blue and white leads from
the terminals of each tank heater.
5. Check for continuity across the terminals of each
tank heater.
SERVICE (cont.)
FIG. 13 TANK HEATERS
If continuity is present as described, reconnect the
wires, the tank heaters are operating properly.
If continuity is not present as described, replace the
open tank heater.
wires, the tank heaters are operating properly.
If continuity is not present as described, replace the
open tank heater.
NOTE- If the tank heater(s) remain unable to heat,
remove and inspect heater(s) for cracks in the sheath.
remove and inspect heater(s) 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, splash guard and
tank inlet gasket. Set all parts aside for reassem-
bly.
tank inlet gasket. Set all parts aside for reassem-
bly.
3. Turn off water supply to the brewer and disconnect
the inlet and outlet water lines to the faucet coil
assembly.
assembly.
4. Disconnect the black wire on the limit thermostat
from the tank heater switch. Disconnect the blue
wire from the limit thermostat to the control ther-
mostat.
wire from the limit thermostat to the control ther-
mostat.
5. Disconnect the black, white and blue wires 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, tank heaters and coil assembly.
9
Remove the two hex nuts securing each tank
heater to the tank lid. Remove tank heater(s) with
gaskets and discard.
heater to the tank lid. Remove tank heater(s) with
gaskets and discard.
10. Install new tank heater(s) with gaskets on the tank
lid and secure with two hex nuts.
11. Install tank lid with limit thermostat, sprayhead
tube, tank heaters, coil assembly using eight #8-
32 hex nut.
32 hex nut.
12. Reconnect the inlet and outlet water lines to the
faucet coil assembly.
13. Secure sprayhead tube to hood using a hex nut.
14. Install sprayhead.
15. Reconnect the wires to the limit thermostat and
14. Install sprayhead.
15. Reconnect the wires to the limit thermostat and
tank heaters and control thermostat. See
Limit
Thermostat and Control Thermostat sections in
this manual when reconnecting wires.
this manual when reconnecting wires.
16. Install fill basin, secure with tank inlet fitting and
gasket. Insert water supply line through grommet
in fill basin.
in fill basin.
P1415.40
28182 090100