8
E.
After the burner has completed pre-purge and established a good pilot flame signal reading, the
main automatic fuel valve will be energized. As when setting up the pilot, static air pressure will
also be evident on the gas manifold. This pressure will increase as the main gas valves open.
The main flame should light immediately. If immediate light off does not occur, it is possible that
air will need to be purged from the main gas line. Adjust main gas pressure regulator (if used) or
combination valve regulator to obtain the desired firing rate pressure.
F.
Adjust burner as necessary to provide smooth ignition of main flame. If flame signal drops
significantly when main fuel valve opens, decrease pilot gas pressure slightly to obtain a
reasonably stable flame signal value.
G.
If required, select and install the main orifice that corresponds to the desired firing rate, see table
4 on page 9. Ensure that the airflow setting provides the correct CO
2
or O
2
levels and other
combustion values at the proper firing input rates. Generally accepted values for natural gas are
8-1/2 to 10% CO
2
or 5-1/2 to 3% O
2
. Equivalent CO
2
readings on propane gas are 10 to 11-1/2%
CO
2
or 5-1/2 to 3-1/2 % O
2
. It is important that the CO (carbon monoxide) level is checked and
held at 0% or minimum (typically under 100ppm or 0.01%). Check with the local gas utility and
any other authorities having jurisdiction before making final burner adjustments.
7.13
Conduct all applicable test procedures shown in the Primary Safety Control manufacturer’s bulletins
included with the burner. Set and check operation of low and high gas pressure switches (if applicable),
all burner and heat exchanger controls, and operating devices. Check blower airflow proving switch by
first closing main gas cock and disconnecting motor lead wire. A properly adjusted air switch should open
within 3 to 4 seconds when the power is removed from the motor.
7.14
Clean up are around the burner and review operating procedures and instructions with owner and/or
operator.
7.15
Post Installation and Operating Instructions close to the burner in clearly visible position for future reference.
