Monarch Oil nozzle 1.25GPH / 45R

This is an oil nozzle with a flow rate of 1.25 GPH, a 45 ° spray angle and an R spray pattern. It is used to atomise fuel oil in a burner, forming the spray that is mixed with air for combustion. The 1.25 GPH figure defines the volume of oil passed per hour at the rated nozzle pressure. The 45 ° angle sets the width of the spray cone, and the R pattern defines the shape of the spray. It is a replacement part for oil-fired burners and boilers that take this nozzle size.

Nozzles of this type are selected by matching the flow rate, spray angle and spray pattern to the burner manufacturer's specification, and by matching the thread and body form to the nozzle holder. Mounting forms differ by thread size and by the length and shape of the body, so the old nozzle must be compared with the replacement before ordering. The nozzle seat and the holder must be clean and undamaged, and the nozzle must be tightened to the torque given by the burner maker. The pump pressure and the filtration upstream of the nozzle must also be checked, since they affect the flow actually delivered.

Nozzles of this type commonly fail by clogging of the internal passages or of the strainer, by wear of the orifice, or by a distorted spray pattern. The equipment then shows a poor flame, delayed ignition, pulsation, soot deposits or a rise in flue gas readings, and in some cases the burner locks out. Checking the spray pattern, the flow rate and the condition of the strainer, together with the pump pressure, shows whether the nozzle is the cause.