IC-SA-1511 (02/2014)
V/LNV Series Manual
3-7
Operation
9.
Check to see that the gas valve has closed tightly. If ignition does not occur, turn the burner switch
“OFF” and allow the programmer to recycle for a new ignition trial.
10.
Turn the burner “ON” and after pilot ignition when the flame relay pulls in, the slow opening, motorized,
main gas valve is energized. The main flame should ignite at this time. The gas valve and air damper
continue advancing until high fire is reached.
11.
Do not repeat unsuccessful light off attempts without rechecking burner and pilot adjustment. Vent fuel
vapors from the combustion chamber after each unsuccessful light off attempt.
12.
Set the gas low fire rate by adjusting the butterfly valve and air linkage.
13.
When low fire is adjusted, shut down the burner.
14.
Restart several times to be sure the low fire setting is suitable. Readjust if necessary. Never start the
burner with fuel vapor in the furnace. In case of an emergency, open the main power switches and close
all fuel valves.
15.
After combustion adjustments are satisfactorily set, allow the heating vessel to slowly reach normal
operating pressure or temperature.
16.
Turn the potentiometer switch to the high fire position. Check high fire at this point using combustion
instruments.
17.
Do not disturb established low fire adjustment. Allow the burner to return to low fire position before
adjusting high or intermediate settings.
Do not repeat unsuccessful light off attempts without rechecking burner and pilot adjustment. Vent fuel
vapors from the combustion chamber after each unsuccessful light off attempt. Set the gas low fire rate by
adjusting the butterfly valve and air linkage. Refer to the adjustment section of this manual. Using the
combustion analysis instrument, adjust the low fire. Typical combustion analysis for low fire is 5% to 6% O
2
on standard turndown systems, and between 6.5% and 9% for higher turndown systems. Verify the
minimum input rate by measuring the gas meter.
When low fire is adjusted, shut down the burner. Restart several times to be sure the low fire setting is
suitable. Readjust if necessary. Never start the burner with fuel vapor in the furnace. In case of emergency,
open the main power switches and close all fuel valves. After combustion adjustments are satisfactorily set,
allow the heating vessel to slowly reach normal operating pressure or temperature.
After the boiler has reached operating temperature or pressure, turn the potentiometer switch in small
increments to the high fire position. Check high fire at this point using combustion instruments. High fire
combustion analysis typically is 3% to 4% O
2
. Verify maximum input rate by measuring the gas meter.
Do not disturb established low fire adjustment. Allow the burner to return to low fire position before
adjusting high or intermediate setting. CO levels should be less than 400 ppm on an air-free basis at all
firing rates, with <50 ppm as the target value.
When conditions covered above are assured, refer to Sections 3.9 and 3.10.
3.8.2 — Oil Burners
1.
The fuel selector switch should be set to “OIL” and the “ON-OFF” switch is in the “OFF” position.
Actuate the manual reset button of the flame safeguard control to close the safety switch contacts.