Bunn TU3 service manual Limit Thermostat, Indication must be

SERVICE (cont.)

LIMIT THERMOSTAT

FIG. 14 LIMIT THERMOSTAT P1276.40

Location:

The limit thermostat is located inside the hood on the tank lid.

Test Procedure:

1.	Disconnect the brewer from the power source and
	remove the black wire from the limit thermostat.
2.	With a voltmeter, check the voltage across the
	black wire removed from the limit thermostat and
	the white wire or red wire on the tank heater ter-
	minal. Connect the brewer to the power source.
	The indication must be:
	a) 120 volts ac for two wire 120 volt models.
	b) 240 volts ac for two wire 240 volt models.

5.With a voltmeter, check the voltage across the ex- posed terminal of the limit thermostat and the white wire from the power cord or the red wire from the power connector. Connect the brewer to the power source. The indication must be:

a)120 volts ac for two wire 120 volt models.

b)240 volts ac for two wire 240 volt models.

c)100 volts ac for two wire 100 volt models.

6.Disconnect the brewer from the power source.

If voltage is present as described, reconnect the blue wire to the limit thermostat. The limit thermostat is operating properly.

If voltage is not present as described, replace the limit thermostat.

Removal and Replacement

1.Remove both wires from the limit thermostat ter- minals.

2.Carefully slide the limit thermostat out from un- der the retaining clip.

3.Carefully slide the new limit thermostat into the retaining clip.

4.Refer to Fig. 15 when reconnecting the wires.

BLU/BLK to

Control

Thermostat

c) 100 volts ac for two wire 100 volt models.

3. Disconnect the brewer to from the power source.

If voltage is present as described, reconnect the black wire and proceed to #4.

If voltage is not present as described, refer to the Wir- ing Diagrams and check the wiring harness.

4.Remove the blue/black wire from the limit ther- mostat.

BLK to Power Cord or

Power Connector

FIG. 15 LIMIT THERMOSTAT TERMINALS

P1800

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