Unigas HR91A, Manual Of Installation, Use And Maintenance

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PART I: SPECIFICATIONS
5
1.0 BURNERS FEATURES
Note: the figure is indicative only
Keys
1 Mimic panel with startup switch
2 Gas filter
4 Gas valve group
5 Cover
6 Flange
7 Blast tube-Combustion head group
8 Oil pressure governor
9 Actuator
10 Adjusting cams
11 Air intake
12 Air pressure switch
13 Oil manifold
14 Head adjusting ring nut
15 Pump
Gas operation: the gas coming from the supply line, passes through the valves group provided with filter and governor. This one for-
ces the pressure in the utilisation limits. The actuators move proportionally the air damper and the gas butterfly valve, in order to
achieve the optimisation of the gas flue values, as to get an efficient combustion.
Light oil operation: the fuel coming from the supply line, is pushed by the pump to the nozzle and then into the combustion chamber,
where the mixture between fuel and air takes place and consequently the flame.
In the burners, the mixture bertween fuel and air, to perform clean and efficient combustion, is activated by atomisation of oil into very
small particles. This process is achieved making pressurised oil passing through the nozzle.
The pump main function is to transfer oil from the tank to the nozzle in the desired quantity and pressure. To adjust this pressure,
pumps are provided with a pressure regulator (except for some models for which a separate regulating valve is provided). Other pumps
are provided with two pressure regulators: one for the high and one for low pressure (in double-stage systems with one nozzle).
The adjustable combustion head can improve the burner performance. The combustion head determines the energetic quality and the
geometry of the flame. Fuel and comburent are routed into separated ways as far as the zone of flame generation (combustion cham-
ber). The control panel, placed on the burner front side, shows each operating stage.
PART I: SPECIFICATIONS
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5
7
6
4
2
1
8
10
12
13
9
14
15