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Gas Fired Steam Tilting Kettles
Thermostat
The thermostat adjustment should not be changed. Check the following before changing the thermostat:
1. With kettle cool, the pressure reading on the pressure gauge should be in the green vacuum zone (below 0 psi). If not,
see "Re-establishing Vacuum" section.
2. Check that the pressure switch is not set too high or too low and causing the out of adjustment condition. A voltmeter
should be used by a properly trained serviceman to determine if the pressure switch or thermostat is actually cycling
the burners. If the pressure switch is found to be the problem, see "Pressure Switch" section.
After verifying that the pressure switch is set and operating properly, the thermostat may be adjusted using the set screw
inside the stem. The thermostat should cycle off at a gauge pressure reading of 30 psi. Turn set screw clockwise to
decrease pressure and counterclockwise to increase pressure.
Pressure Switch
The pressure switch should not be adjusted until it is determined to be the cause of an operating pressure deficiency. See
"Thermostat" section to determine if the source of difficulty is the pressure switch or thermostat.
The major difficulties caused by pressure switch mis-adjustment are:
1. Pressure relief valve opening, especially on preheat from a cold start to 275 degrees Fahrenheit (135 °C). (Pressure
switch set too high.)
2. Burners are being shut down by pressure switch, not the thermostat. (Pressure switch set too low.)
The pressure switch is preset for proper operation from the factory. It is adjusted to the maximum pressure, however
not high enough to cause the pressure relief valve to open. This setting will be slightly different on different kettles due
to variations in the pressure relief valves. During preheat to the maximum thermostat setting (275 degrees Fahrenheit)
(135 °C), from either a cold condition or a lower temperature setting, the temperature may overshoot the thermostat
setting and shut down the burners by the pressure switch. This is normal, however, after the kettle cycles several times
(empty) the thermostat will begin cycling the unit.
To Adjust Pressure Switch
1. To obtain access to the pressure switch, the front panel must be removed. Remove the screws on either side of the
panel. Be sure to support the panel to avoid excessive strain on the wiring.
2. To increase the pressure setting turn the white ribbed knob clockwise; to decrease the pressure, turn it
counterclockwise. Use the centre of the black ring as an indicator.
3. With the kettle empty and completely cold, bypass the thermostat by moving the single terminal side wire to the
double terminal side connector on the thermostat. Turn kettle on.
4. Pressure in kettle (read pressure gauge on front panel) should reach a maximum of 35 psi and pressure relief valve
should not open. Kettle pressure may rise 3 or 4 psi even after burners shut down.
5. Relief valve should not open when kettle pressure is 40 psi; pressure switch setting is satisfactory.
6. If relief valve opens, reduce setting on pressure switch, cool kettle completely by running cold water through it and
repeat steps 3 - 6.
7. If pressure in kettle is below 30 psi when burners shut off, increase setting of pressure switch, cool kettle completely
by running cold water through it and repeat steps 3 - 7.
8. When adjustment is complete, move wire from shorted terminal on the thermostat back to the appropriate terminal
and replace the front panel.
INSTALLATION & OPERATION MANUAL 10325 REV 1 (11/21)
Service
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