INSTALLATION AND OPERATION MANUAL, DIRECT STEAM KETTLES MOUNTED ON GAS
BOILER CABINET BASE, GMT-6, GMT-10, GMT-6-6, GMT-10-6, GMT-10-10
PART NUMBER 10072R1
23
2005-09-21
TO CALIBRATE PRESSURE SWITCHES
(Continued)
Pressure switch range is from 1 to 15 psi.
Adjust all settings to maximum on high signal adjustment screw on pressure switches.
Adjust in the following sequence:
- High limit pressure switch.
- Override pressure switch.
- Operating pressure switch.
- Turning screw clockwise to increase, counterclockwise to decrease pressure.
- Use relief valve to release pressure from boiler for setting adjustments.
1. HIGH LIMIT PRESSURE SWITCHES
Allow pressure to build until unit shuts off. This should occur at 15 psi. Set the high signal
to switch at 14.5 psi on the gauge and the low signal to 13.0 psi.
2. OVERRIDE PRESSURE SWITCHES
Allow pressure to increase to 13 psi. Set the high signal to switch at 13 psi on the gauge
and the low signal to 11 psi.
3. OPERATING PRESSURE SWITCHES
Set the high signal to switch at 11 psi on the gauge and the low signal to 9 psi.
4. Release pressure in boiler to below 9 psi. Burner will come on. Once pressure has
reached 11 psi, burners will shut off. Repeat this process several times to make sure
burners come on at 9 psi and shut off at 11 psi.
Once completed, pressure switches have been calibrated.
Should your unit not have the High Limit pressure switch, start procedure at Override pressure
switch.
SERVICE
Contact your local authorized service office for any repairs or adjustments needed on this
equipment.
