Unigas HR91A, Инструкция по установке, использованию и обслуживанию

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PART III: OPERATION
34
5.0
AIR FLOW AND FUEL ADJUSTMENT
5.1 Adjustments - brief description
Adjust the air and gas flow rates at the maximum output (“high flame”) first, by means of the air damper and the adjusting cam respec-
tively.
z
Check that the combustion parameters are in the suggested limits.
z
.Check the flow rate measuring it on the counter or, if it was not possible, verifying the combustion head pressure by means of a
differential pressure gauge.
z
Then, adjust the combustion values corresponding to the points between maximum and minimum: set the shape of the adjusting
cam foil. The adjusting cam sets the air/gas ratio in those points, regulating the opening-closing of the throttle gas valve.
z
Set, now, the low flame output, acting on the low flame microswitch of the actuator in order to avoid the low flame output increasing
too much or that the flues temperature gets too low to cause condensation in the chimney.
WARNING! During commissioning operations, do not let the burner operate with insufficient air flow (danger of
formation of carbon monoxide); if this should happen, make the fuel decrease slowly until the normal
combustion values are achieved.
WARNING! the combustion air excess must be adjusted according to the values in the following chart.
Recommended combustion parameters
Fuel
Recommended (%) CO
2
Recommended (%) O
2
Natural gas 9 ÷ 10 3 ÷ 4.8
Light oil 11.5 ÷ 13 2.9 ÷ 4.9
LPG 11 ÷ 12 2.8 ÷ 4.3