Product overview
Details that help confirm the fit.
The Danfoss BFP 21 L3 is a compact gear-type fuel pump designed for single-stage domestic and light commercial oil burners. The L3 configuration indicates counter-clockwise shaft rotation and size 3 capacity, providing a nominal nozzle output of 24 l/h at reference conditions of 4.3 cSt viscosity, 10 bar pressure and 2800 rpm.
The pump is suitable for light heating oil, kerosene and compatible biofuel blends, subject to the exact product code and fuel-compatibility rating. It can be configured for either one-pipe or two-pipe fuel systems.
Fuel is drawn through the replaceable cartridge filter and transferred to the gear set, where its pressure is increased. The integrated pressure regulator maintains a stable nozzle pressure according to the value selected using the front-mounted adjustment screw.
The BFP 21 incorporates a normally closed solenoid valve that provides immediate fuel shut-off when electrical power is removed. When the valve is energised, fuel is released to the nozzle outlet. This arrangement provides controlled burner start-up and rapid fuel cut-off when the burner stops.
In a two-pipe installation, excess fuel is returned to the storage tank and the pump is self-priming. In a one-pipe installation, excess fuel circulates internally after the pump has been configured correctly by removing the changeover screw and sealing the return connection. Bleeding in a one-pipe system must be performed through the nozzle outlet or pressure-gauge port.
Typical applications include domestic oil burners, heating boilers, hot-water boilers, kerosene burners and light commercial heating equipment. Installation, pressure adjustment, fuel-system conversion and commissioning must be performed by qualified personnel in accordance with official Danfoss instructions and applicable regulations.
Model, voltage, rotation, pressure range and mounting can vary. Final compatibility is confirmed against the nameplate or existing component.
