Delavan 8.00GPH, 45B (7) nozzle

This is a Delavan oil nozzle, catalogue article 345.892.201, with manufacturer codes 00800-45B7, 3042251 and 345.892.201. It is a precision consumable part that atomises fuel oil into a fine spray for complete combustion. The nozzle is a component of the oil burner’s fuel delivery system, fitted into the burner’s blast tube or combustion head, and works in conjunction with the oil pump, solenoid valve and, where fitted, a preheater. The condition of this part directly affects flame stability, ignition reliability and combustion efficiency. Nozzles of this type are selected by three parameters: flow rate (given here as 8.00 GPH), spray angle and spray pattern. The designation “45B” indicates an angle of 45 degrees and a specific pattern type, but the exact meaning of the pattern code should be verified against the burner manufacturer’s data. All three values must match the burner’s specification. Using a nozzle with the correct flow rate but a different pattern can cause sooting, pulsation or unstable ignition. When replacing, always fit a nozzle with the same GPH rating, angle and pattern as the original. The thread size is standard for this class of nozzle, but it is good practice to confirm that the new nozzle seats correctly in the adapter. As a consumable item, this nozzle should be replaced at every annual service or sooner if combustion tests show deteriorating performance. Debris or wear in the orifice alters the spray quality, so handle the nozzle carefully and do not attempt to clean a blocked nozzle – install a fresh one. Always use a torque wrench to the recommended setting to avoid distortion.