Figure 19: Preliminary Adjustment of Burner Air Band and Air Shutter
i.When ignition is established, make a preliminary burner air adjustment to attain a clean combustion flame. Generally, the burner bulk air band should be about 3/16 inch open and the opening of the burner air shutter set in the range of “2” to “7”, refer to Figure 19.
Replace the inspection cover above the burner.
j.After the appliance is warmed up to a steady state condition (about 15 minutes), the final burner adjustment should be made using combustion instrumentation for smoke, carbon dioxide (CO2)
or excess oxygen (O2), and flue gas temperature. In order to achieve the most efficient combustion, the following steps must be taken:
COMBUSTION HEAD SETTING FOR 2-STAGE RIELLO BURNER:
This is done when fitting the nozzle, with the blast tube removed. It depends on the output of the burner and is carried out by rotating the regulating rod, till the terminal plane of the blast tube is level with the
In figure 20 the combustion head is set for an output of 0.75 GPH at 130 psi, while the shutter is level with set- point 2.5, as required by the above schedule.
Figure 20
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