dunphy TAD4, Руководство по эксплуатации

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Operating Instructions For TD/TAD4 Dual Fuel Burner
June 13 73 of 165 TD/TAD4 Manual Rev 4
over two pluses on the pump motor. Do not swap the mains electrical feed as this will also
reverse the burner fan motor rotation.

Start the burner and allow to go through pre-purge cycle. When the burner reaches its
ignition position, the ignition transformer is switched on, followed by the fuel pump motor,
and then the two solenoid valves, which should result in the burner lighting.

Set the pump pressure to approx 25 bar.

Adjust the low fire air position to give the following figures:
Carbon Dioxide: 11 - 14%
Smoke Number: 0 - 1 (
Excess Oxygen: 3 - 6%
Nett Flue Gas Temperature: 180 - 220ºc
Step 2

Allow burner to move to High Fire position. On its way to High Fire, the V2 Oil Valve will
energise, thus passing oil into the second nozzle.

Once at High Fire, adjust air damper to give combustion figures similar to above.

Switch between Low and high Fire, checking the firing rate and combustion, ensuring that
consistent figures and smooth, reliable light-up are being obtained.

Listen for signs of flame instability.

With the burner firing, remove and cover the photocell, ensuring that the burner goes
immediately to lockout.

Warm up the boiler or raise steam slowly, and in accordance with the manufacturer's
instructions.

After running for a reasonable amount of time, remove the combustion head and check for
any oil impingement, oil leaks, or fouling at the flame plate.

If necessary, make adjustments to the combustion head to cure this.
Check the flame ring for indications of overheating or impingement by the oil spray.
The basic, relative positions of the combustion head components are given in section 3 of this
manual, but the principles to be followed are that:-
1. The ignition electrodes must be positioned so that the spark, which `strikes` at the narrowest
point is blown forward by the combustion airflow on to the widest point of the `horns`. This
will ensure that the arcing takes place within the cone of atomised fuel, with a consequent
immediate ignition of the fuel.
Note that if the electrodes are set too far forward, they will be subjected to continuous
impingement by un-burnt fuel, some of which will carbonise, quickly reducing the intensity
of the spark and leading to poor ignition.
2. The relative position of the flame ring must give a flame which is `anchored` on to the front
face of the ring. The slotted vanes must be opened enough to allow the passage of an
adequate amount of air, which because of the swirl effect imparted, will be a major
stabilising factor. If the vane gap is irregular, the flame shape will be affected and soot will
build up at the points which restrict the air flow.
If the nozzle is too near to the flame ring, the flame will tend to `lift off`, giving very
unreliable ignition and a degree of instability which will make reliable operation, especially
when modulating from high to low fire.
3. The combustion head as an assembly, must be central in the draught tube, otherwise the air
velocity round the outside of the flame ring ( and therefore of the flame ) will vary in