Bunn Hot Water Dispencer H5X

Warning: Disconnect the dispenser from the power source before starting the test

Thermistor disconnected from J5 on control board

Enter the resistance across thermistor

Resistance range is approximately 9KOhm room temperature to approximately 2KOhm 200°F

Disconnect the dispenser from the power source

Was resistance present as described?

Sign off on the steam sensor test

Replace the Thermostat (H5M, HW2 & OHW Only)

Remove both wires from the thermostat terminals

Remove the top lid from the dispenser to gain access to the thermostat bulb

Remove the thermostat bulb by firmly pulling up on the capillary tube at the tank. This will disengage the grommet from the tank

Remove the two #6-32 screws holding the thermostat to the mounting bracket

Fasten the new thermostat to the mounting bracket

NOTE: Make sure that the capillary tube is away from any electrical termination and is not kinked

Slide the grommet to the red mark on the capillary tube

Insert the bulb through the hole in the tank and press the grommet firmly and evenly so that the groove in the grommet fits into the tank

Disconnect the dispenser from the power source

Disconnect the black wire from the contactor coil to the limit thermostat and black wire from the red wire on the main harness on two wire 240V models

Check the voltage across the red wire and black wire with a voltmeter

Disconnect the dispenser from the power source

If voltage is present as described, proceed to #5. If voltage is not present as described check the wiring harness

Check for continuity between the left and right terminals on the contactor coil

If continuity is present as described, reconnect the wires and proceed to #6. If continuity is not present as described, replace the contactor

Disconnect the dispenser from the power source

Voltage across the black wire on the thermostat and the white or red wire at the terminal block

If voltage is not present as described, refer to the Wiring Schematics and check the dispenser wiring harness

Voltage across the blue/black wire on the thermostat and the white or red wire at the terminal block when the thermostat is turned ON

Voltage present as described when thermostat is ON

Voltage not indicated when the thermostat is turned OFF

If voltage is not present as described, replace the thermostat

Check the valve for coil action

If no sound is heard, proceed to next step

Check for blockage in the valve

Connect voltmeter leads to the coil terminals

If voltage is present but no coil action is observed, valve is defective

Check the dispenser wiring harness

Check the control board for proper operation

Disconnect the dispenser from the power source and allow to cool