Bunn TU5Q 业主指南

Page 17

SERVICE (cont.)
CONTROL THERMOSTAT

FIG. 8 CONTROL THERMOSTAT

P2143.35

Location:

The control thermostat is located inside hood on

the right side.

Test Procedures:

1. Disconnect the brewer from the power source.

2. Locate the blue/black wire on the control thermo-

stat.

3. With a voltmeter, check the voltage across the blue

wire on the control thermostat and the white or

red wire on the tank heater. Connect the brewer

to the power source. The indication must be:

a) 120 volts ac for 2-wire 120 volt models.

b) 208 volts ac for 3-wire 120/208 volt models.

c) 240 volts ac for 3-wire 120/240 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 wir-

ing 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

or red wire on the tank heater when the control

thermostat is turned fully clockwise. Connect the

brewer to the power source. The indication must

be:

a) 120 volts ac for 2-wire 120 volt models.

b) 208 volts ac for 3-wire 120/208 volt models.

c) 240 volts ac for 3-wire 120/240 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 5.5" above the bulb, the

control thermostat is operating properly.

If voltage is not present as described, replace the

thermostat.

Removal and Replacement:

1. Remove both wires from the control thermostat

terminals.

2. Remove the thermostat capillary bulb by firmly

pulling up on the capillary tube at the tank lid. This

will disengage the grommet from the tank lid.

3. Remove the #8-32 screw holding the control

thermostat to its bracket.

4. Slide the grommet to the line 5.5" above the bulb

on the new capillary tube.

5. Insert the capillary bulb through the hole in the

tank lid and press the grommet firmly and evenly

so that the groove in the grommet fits into the tank

lid.

6. Carefully bend the capillary tube so that the tube

and bulb inside the tank are in a vertical position.

NOTE – The capillary tube must be clear of any electri-

cal termination and not kinked.
7. Fasten the new control thermostat to its bracket.

8. Refer to Fig. 9 when reconnecting the wires.

9. Adjust the control thermostat as required.

FIG. 9 CONTROL THERMOSTAT TERMINALS

MINUT

MINUTE

NN-O-MATI

P/N 05791-0006 120 V

BUNN

OFF

BUNN

OFF

BLK to Tank Heater

BLU to Limit Thermostat

P2090.80

10777 041500