Welbilt Cleveland KGT12TGB, Installation, Operation, Maintenance, Parts & Service

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G/ CALIBRATING PROCEDURE
1. Kettle must be empty when this procedure is executed.
2. Insure the unit has a vacuum before you begin calibrating procedures. If unit
requires venting see REFERENCE SECTION (KETTLE VENTING
INSTRUCTIONS).
3. Turn kettle ON and set temperature dial to 10 (Max.).
4. Allow the unit to cycle twice (the green light must go on and off).
5. Check temperature of the inner kettle surface with a digital surface thermometer.
For accurate readings move probe around bottom of kettle to locate the hottest
location.
6. Temperature should be between 260° F and 265° F. Pressure gauge should read
between 20 - 28 PSI.
7. Using a screw driver adjust temperature by turning the potentiometer on the
black box. Turn very little. Turn clockwise to INCREASES and counter-clockwise
to DECREASE temperature.
8. Allow the unit to cycle twice.
9. Re-check temperature.
10. Repeat steps 7 - 9 until unit is calibrated.
260º - 265º
MAXIMUM
KETTLE
TEMPERATURE
265º
✔
Take reading
from hottest
spot in bottom
of kettle.
OPERATING SEQUENCES
1. Turn On-Off / Temperature Dial * - 14 volt transformer is energized and powers solid state control system.
- Temperature knob is turned up and control box calls for heat.
- Relay (RY-1) closes and powers 24 volt transformer.
- Ignition control box is powered.
3. Ignitor Sparks * - Gas valve is energized.
- Ignitor sparks and ignition occurs.
4. Temperature Reached * - Solid state controls senses temperature reached.
- Relay (RY-1) opens and 24 volt transformer loses power.
- Ignition control box is turned off.
- Gas valve closes.
5. Maintaining Temperature * - Solid state controls senses temperature drop.
- Relay (RY-1) closes and powers 24 volt transformer.
- Ignitor control box is powered.
- Steps three and four are repeated.
SOLID STATE CONTROL SEQUENCE
Our solid state controls consist of the following components.
On-Off / Temperature * Provides or interrupts electrical power to the control system.
Dial (Potentiometer) Rotate to change resistance from 0 to 50,000 ohms. This resistance is compared to the resistance on the thermistor using a voltage
comparator circuit inside the control box.
If the resistance is lower than the thermistor resistance then the control box will provide 14v dc to pin #8. The green indicator light
illuminates and the control relay (RY-1) is energized closed to provide power to the heating system.
Control Box * Analyzes inputs from water level probe, tilt switch, potentiometer, thermistor. Energizes control relay (RY-1)
Water Level Probe * Senses water in jacket.
Tilt Switch When kettle is in upright position tilt switch is closed to complete circuit between pin #8, the relay (RY-1) and green indicator light. *
Thermistor * The thermistor resistance decreases as temperature increases. When the thermistor resistance equals the potentiometer then 14v dc
is removed from pin #8. The control relay (RY-1) returns to the normally open position.
Green LED Light Indicates that the control box is calling for heat. Pin #8 powered.
Red LED Light Indicates that the water level probe is not immersed in water. Not enough water in the jacket or kettle tilted.
Relay (RY-1) When energized allows the heating circuit to function. Electric elements or gas burner system.
NOTES:
* A ground loop circuit must be established between kettle body, water in jacket, water level probe and control box. If this loop is present, it
indicates that there is sufficient water in the kettle for safe operation.
* If there is not sufficient water in the jacket then the loop is broken and the control box will prevent 14v DC from being supplied to pin #8.
The control relay (RY-1) will remain (or return) to the normally open position and the unit cannot heat. The red LED light will be illuminated.