Hot water pressure washers often include oil burners with fuel nozzles from Delavan Spray Technologies. Delavan has been designing and manufacturing nozzles for the oil heating industry for over 60 years. They are recognized as a worldwide leader in spray nozzles for combustion applications from domestic heating to commercial boilers.

Fuel nozzles found in most hot water pressure washer oil burners have three main characteristics. The first is the flow rate, measured in gallons per hour. This can range from .5 gph to typically no more than 6.5 gph. The second is the spray angle, which can be 30°, 45°, 60°, 70°, 80° or 90°. Lastly, the cone type is a key characteristic of these nozzles. Type A nozzles have a hollow fuel cone, while type B is a solid cone.

HOLLOW-CONE TYPE A

Hollow-Cone Type A nozzles are mainly used on burners with a hollow cone air pattern and for throughputs up to 2.00 gph. The droplet distribution is concentrated on the outside of the cone and results in good ignition and low-noise combustion.

SOLID-CONE TYPE B

Solid-Cone Type B nozzles produce a spray that distributes droplets fairly uniformly throughout the complete pattern. The spray pattern becomes progressively more hollow at higher flow rates, particularly above 8.00 gph. Type B nozzles provide smooth ignition and efficient combustion, particularly in larger burners.

Delavan fuel nozzles are constructed of five basic parts. The nozzle body can be made of either brass or 416 stainless steel. The orifice disc and distributor are each made of 416 stainless steel, and the retainer can be either brass or 416 stainless steel. A filter is included at the base of the nozzle body as well. Delavan oil burner fuel nozzles have thread measuring 9/16” - 24 UNEF.