Nortec GS Series - Manual (Page 40)

37 | GS Series Installation
Testing the Ignition Safety Shut-Off
Test the ignition system safety shut-off in the following method.
Close the shut-off valve in the gas supply line.
Set the demand signal to the humidifier to 100%.
Ensure all external controls connected to the security loop are closed.
Switch the humidifier on.
At the completion of the float test, the humidifier will begin the combustion sequence by energizing the
combustion blowers.
All blowers will run at full output for 30 seconds to pre-purge the combustion chamber. During this time the
controller will monitor that all air proving switches closed to prove air flow.
The igniter(s) will be energized for 15 seconds, allowing it time to heat to the appropriate ignition
temperature and the gas valve will be energized.
After 4 seconds both the gas valve(s) and the igniter will be de-energized.
After three trials for ignition (complete with pre-purge) the red LED on the ignition control module will begin
blinking to indicate a safety lockout and a fault message will be displayed on the humidifier display.
Note: On multiple burner models, each burner tries to ignite in sequence. It is necessary to wait for all
burners to cycle to complete the test.
Manually re-open the gas supply to the humidifier. No gas should flow to the burner(s).
To reset the humidifier, shut off the power switch, and then turn the power back on.
Starting the Humidifier
Once the tank has been filled and the ignition safety test has been performed as outlined above, the
humidifier is ready to be put into operation.
Verify that the inspection checklist has been completed and all deficiencies with the installation have been
corrected.
Open the shut-off valve in the gas supply line.
Open the shut-off valve in the water supply line.
Ensure all external controls connected to the security loop are closed.
Verify that the building demand signal is connected to the humidifier.
Install and secure all cabinet service doors.
Switch the humidifier on.
At the completion of the float test, the humidifier will begin the combustion sequence and each burner will
ignite in sequence.
Depending on the system demand the combustion blowers will modulate faster or slower to control the
burner input.
The water in the tank will heat up and begin to boil, delivering steam to the distribution system.
During the boiling sequence the water fill valve will periodically activate to replenish water that has
evaporated from the tank.
Once the humidity requirements have been satisfied (demand drops below minimum %) all gas valves will be
de-energized and the blowers will be shut off after performing a post purge of the combustion chamber.