5. Remove kettle thermistor and allow toNo Replace defective thermistor cool. Remove edge connector from
control box. Test resistance across edge connector's pins #2 and #7. Is it approximately 100,000 ohms?
6.Turn the potentiometer on the control box clockwise to increase the maximum operating temperature. Does the kettle now achieve maximum operating pressure of
Yes | Kettle is operating correctly. |
No | Spray contact cleaner on control |
| terminals and edge connector. Try box |
| again. If problem still exists, replace |
| defective control box. |
C/ Problem: Kettle is overheating.
Possible Causes |
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|
|
| |
1. | Defective thermistor | 2. | Defective potentiometer | 3. | Defective 12 VDC relay. |
. |
|
| (temperature control). | 4. | Defective control box. |
Fault Isolation Procedure
Step Test
1.Does the green LED turn off even though the contactors remain energized?
2.Unplug the control box and measure the resistance across the potentiometer (temperature control), Is the resistance approximately 0 ohms at maximum and 50,000 ohms at minimum setting?
Result | Remedy |
Yes | Replace defective 12 VDC relay. |
No | Go to step #2. |
Yes | Go to step #3. |
No | Replace defective thermistor. |
3.Remove kettle thermistor and allow to cool Remove edge connector from control box. Test resistance across edge connector’s pins #2 and #7. Is it approximately 100,000 ohms?
Yes | Go to step #4. |
No | Replace defective thermistor. |
4.Turn the potentiometer (temperature control) on the control box counter- clockwise to decrease the maximum operating temperature. does the kettle continue to overheat?
Yes | Spray contact cleaner on control box terminal |
| and edge connector. Try box again. If problem |
| still exists, replace defective control box. |
No | Kettle is operating correctly. |
D/ Problem: Red LED remains illuminated even though water has been added.
Possible Causes
1.Defective low water level probe
Fault Isolation Procedure
Step Test
1.Remove wire from low water level probe and ground the wire to the body of the kettle. Does the red LED turn off?
2.Defective control box.
Result | Remedy |
Yes | Replace or clean defective low water |
| level probe. |
No | Spray contact cleaner on control box |
| terminals and edge connector. Try box |
| again. If problem still exist, replace |
| defective control box. |
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