CleaverBrooks 4WI, Руководство по эксплуатации, обслуживанию и запасным частям

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750-211 (revised 2009)
Promethean Boilers, Model 4WI Manual 2-15
2.11 — Atomizing Air
The ignition transformer supplies high voltage current for the igniting spark. A gas pilot has a single electrode and
a spark arcs between the tip of the electrode and the wall of the tube surrounding it. A light oil pilot has two elec-
trodes and the arc is between their tips. The pilot solenoid valve and the transformer are de-energized after main
flame is ignited and established.
Fuel for the gas pilot is supplied from the utility’s main, or from a tank (bottle) supply. Secondary air flows into and
mixes with the pilot gas stream to provide an adequate fuel and air mixture for combustion.
Insurance regulations may required two gas pilot solenoid valves with a normally open vent valve between them.
The vent valve closes when the gas pilot valves open, and opens when the gas pilot valves shut to vent gas, should
any be present in the pilot line during the de-energized period of the gas pilot valves.
Fuel for a light-oil pilot is provided from the line that supplies oil under pressure for the main flame. A solenoid
actuated valve controls flow of oil to the pilot nozzle. The valve is energized simultaneously with the ignition trans-
former at the beginning of the ignition cycle and is de-energized after main flame is ignited and established.
2.11 — Atomizing Air
Air for atomizing the fuel oil (referred to as “primary” air) is pumped by the air pump into the air-oil receiver tank
and delivered under pressure through a manifold block to the oil burner nozzle.
The atomizing air mixes with the fuel oil just prior to the oil leaving the nozzle.
Atomizing air pressure is indicated by the air pressure gauge on the burner gun.
Air pressure from the pump also forces sufficient oil from the
tank to the pump bearings to lubricate them and also to provide a
seal and lubrication for the pump vanes. As a result, the air deliv-
ered to the tank contains some lube oil; however, most of it is
recovered through baffles and filters in the tank before the air
passes to the burner.
Some of the primary air is also used to assist the oil pressure reg-
ulators of the fuel oil controller. Further explanation is given in
Chapter 5.
FIGURE 2-15.
Air-Oil Receiver Tank