heating device in which fuel oil is mixed with air under controlled conditions. In most burners oil is supplied under pressure to an atomizing nozzle to produce a fine spray, to which air is added by a motor-driven fan. As the cone-shaped spray emerges from the nozzle, ignition is usually supplied by an electric spark to start the burner. Starting and shut-off are normally controlled by thermostat. In commercial-industrial types of burners, heavier fuel oil is used, requiring mechanical atomization
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