Monarch 4.00GPH, 60HO nozzle

This is an oil nozzle from Monarch, catalogue article 732.892.160 (manufacturer codes 0986723 and 732.892.160). The product designation indicates a rated flow of 4.00 GPH and a 60‑degree spray angle. An oil nozzle of this type is a precision consumable component that atomises fuel into a fine conical spray for complete combustion. It threads into the burner head and is fed by the oil pump; the solenoid valve and preheater (if fitted) control fuel delivery and viscosity. When replacing a nozzle, the flow rate, spray angle and spray pattern must all match the burner manufacturer’s data plate. The spray pattern can be hollow, solid or semi‑solid; the correct combination ensures the flame sits properly in the combustion head. A nozzle with the right rating but a wrong pattern will cause sooting, pulsation or unstable ignition. Always confirm the three parameters from the burner specification before installing a new nozzle.