HARDI electrical lift pumps are membrane pumps, which are typically used to feed gasoline and diesel engines, or mounted as auxiliary pump to the engine's mechanical feed pump. The HARDI pumps are used on a wide range of applications, such as Generator, boats and vehicles.

The pump operates by moving the diaphragm in a swinging motion, causing pressure and negative pressure in the pump chamber alternately. In both inlets and outlets there is a non-return valve that only allows liquid to flow in one direction, respectively. Into the pump chamber at suction, and out of the pump chamber by pressure. To create suction, the membrane is affected by an electric coil, and the spring presses the membrane back, causing pressure.

The HARDI pumps are produced with 3 different pumping capacities in respectively. 6V, 12V or 24V DC, as well as 9 different designs of the end cap with connection of fuel hoses.

The pump elements 11, 22 and 77 are 6V DC, while the elements 33,44,88,99 and 100 are available in both 12V and 24V DC.

Examples of pump designation:
Designation 18812 is read as 1 88 12, meaning end cap type 1, pump element 88, supply voltage 12V DC.

Designation 8812-3 is read as 88 12-3, which means pump element 88, supply voltage 12V DC, end cap type 3.