Bunn STFA, STA, SA service manual SERVICE cont, Solenoid

SERVICE (cont.)

SOLENOID VALVE (Models ST, STA, STF & STFA)

P1587

FIG. 8 SOLENOID

Location:

The solenoid valve is located inside the front inspection panel on the center lower part of the com- ponent mounting bracket.

Test Procedures:

1.Disconnect the brewer from the power source.

2.Disconnect the wires (FIG. 9) from the solenoid valve. With the "ON/OFF" switch in the "ON" upper position press the start switch.

3.Check the voltage across the two wires with a voltmeter. 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 Wiring Diagrams and check brewer wiring harness.

5.Check for continuity across the solenoid valve coil terminals.

If continuity is present as described, reconnect the wires (FIG. 9) to the solenoid.

If continuity is not present as described, replace the solenoid valve.

6.Check the solenoid valve for coil action. Connect the brewer to the power source. With "ON/OFF" switch in the "ON" upper position press start switch and listen carefully in the vicinity of the solenoid valve for a" clicking" sound as the coil magnet attracts.

7.Disconnect the brewer from the power source.

If the sound is heard as described and water will not pass through the solenoid valve, there may be a blockage in the water line before the solenoid valve or, the solenoid valve may require inspection for wear, and removal of waterborne particles.

If the sound is not heard as described, replace the solenoid valve.

Removal and Replacement:

1.Remove the wires from the solenoid valve.

2.Turn-off the water supply to the brewer.

3.Disconnect the water lines to and from the sole- noid valve.

4.Remove the two #8-32 screws securing the so- lenoid mounting bracket to the component bracket. Remove solenoid bracket and solenoid valve as an assembly.

5.Remove the two #10-32 screws and lockwashers securing the solenoid valve to the solenoid bracket.

6.Using two #10-32 screws and lockwashers in- stall new solenoid valve on solenoid mounting bracket.

7.Using two #8-32 screws install solenoid valve and bracket to the component bracket.

8.Securely fasten the water lines to and from the solenoid valve.

9.Refer to FIG. 9 when reconnecting the wires.

P1588

FIG. 9 SOLENOID TERMINALS

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