Bunn CW APS Service Manual

Page of 33
Page 16
SERVICE (cont.)
CONTROL THERMOSTAT
LATE
MODELS
Location:
Early Models: The control thermostat is mounted
on a bracket inside the hood on the right side just in
front of the tank lid.
Late Models: The control thermostat is located
inside the trunk on the left side of the component
bracket.
Test Procedures:
1. Disconnect the brewer from the power source.
2. Locate the blue wire on the control thermostat.
3. With a voltmeter, check the voltage across the blue
wire on the control thermostat  and the white in-
sert  on  two pole 100 or 120 volt terminal block or
three pole 120/240 volt terminal blocks and the red
insert on two wire 200 volt or 240 volt terminal
block. Connect the brewer to the power source.
The indication must be:
a) 120 volts ac for two wire 120 volt models and
three wire 120/240 volt models.
b) 200  to 240 volts ac for two wire 200 or 240 volt
models.
c) 100 volts ac for two wire 100 volt models.
4. Disconnect the brewer from the power source.
If voltage is present as described, proceed to #5.
If voltage is not present as described, refer to the
wiring diagrams and check the brewer wiring harness.
5. Locate the black wire on the control thermostat.
6. Gently remove the capillary bulb and grommet
from the tank.
7. With a voltmeter, check the voltage across the
black wire of the control thermostat and the white
insert on the two pole 100 or 120 volt or three pole
120/240 volt terminal block and the red insert on
the two pole 200 volt or 240 volt terminal block
when the control thermostat is turned "ON" (Fully
clockwise). Connect the brewer to the power
source. The indication must be:
a) 120 volts ac for two wire 120 volt models and
three wire 120/240 volt models.
b) 200 to 240 volts ac for two wire 200 volt or 240
volt models.
c) 100 volts ac for two wire 100 volt models.
8. Disconnect the brewer from the power source.
If voltage is present as described, reinstall the capillary
tube into the tank to the line 4.5" above the bulb, the
control thermostat is operating properly.
If voltage is not present as described, replace the
thermostat.
EARLY
MODELS
P1137.40
P1127.40
10690 062300
FIG. 2 CONTROL THERMOSTAT