Delavan 0.55GPH, 80W (1) nozzle

This is an oil nozzle from Delavan, a precision consumable part that atomises fuel oil into a fine spray cone for complete combustion. The spray pattern, flow rate and angle together determine how the flame sits inside the combustion head. Nozzles of this type are selected strictly by three parameters: flow rate in GPH at the reference pressure, spray angle (typically between 30 and 80 degrees), and spray pattern (hollow, solid or semi-solid). Using a nozzle with the correct flow rate but the wrong pattern or angle can cause sooting, flame pulsation or unstable ignition, so all three must match the burner data plate. This specific article is listed with a rating of 0.55 GPH and an 80-degree angle; the spray pattern is not specified in the catalogue data, so it must be verified against the original burner specification before replacement. When replacing an oil nozzle, inspect the old nozzle for its stamped markings to confirm the exact rating, angle and pattern. Even a small deviation in flow rate or angle can shift the flame shape and impair heat transfer or cause carbon deposits on the blast tube. The nozzle threads are standard, but thread size is not given here; always check compatibility with the burner’s nozzle holder. Because the nozzle is a wear item subject to erosion from fuel impurities, it should be replaced at every burner service interval to maintain correct atomisation and avoid soot build-up in the combustion chamber.