Bunn H5X service manual Service Limit Thermostat, Test Procedure

SERVICE (cont.)

Limit Thermostat

Location:

The limit thermostat is located on the tank lid.

To test the limit thermostat, access will also be needed to the terminal block located at the rear of the dis- penser.

Test Procedure:

1.Disconnect the dispenser from the power source.

2.There are two black wires on the limit thermostat terminals. One comes from the terminal block. The other goes directly to the tank heater terminal. Re- move the black wire at the limit thermostat coming from the terminal block.

3.Check the voltage across the black wire removed from the limit thermostat and the white wire or red wire of the terminal block with a voltmeter. Connect the dispenser to the power source. The indication must be:

a.) 100 to 120 volts ac for 100 to 120 volt models or

b.) 200 to 240 volts ac for 200 to 240 volt mod- els

or

c.) 230 volts ac for 230 volt models.

4.Disconnect the dispenser from the power source.

If voltage was present as described, reconnect the black wire and proceed to #5.

If voltage was not present as described, refer to the Wiring Diagrams and check the dispenser wiring har- ness.

5.Check for continuity across the terminals of the limit thermostat.

If continuity is not present as described, the circuit is broken. Press the reset button of the limit thermostat and recheck for continuity.

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

Removal and Replacement:

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

2.Remove the two #10-32 nuts attaching the limit thermostat to the top of the tank.

3.Install the new limit thermostat and secure into place with two #10-32 nuts.

4.Refer to FIG. 4 when reconnecting the wires.