Borehole pump

A borehole pump is one that is placed in a water source, such as a groundwater well, from where it is able to pump water under very high pressure through the delivery outlet. This model pump is better suited for this job than the self-priming ones (such as garden/booster pumps), which means it is ideal to be used at a water depth that exceeds eight metres. A borehole pump is characterised by its long, narrow pipe, which is suitable for wells/boreholes with a minimum diameter of 4” (10 cm).

Borehole pumps consist of three parts: the motor housing, the pump body, and the suction grid. The motor housing steers the pump body, allowing it to pump water, which enters it through the suction grid. The pump body is fitted with several impellers. The more impellers, the higher the pressure and flow rate it can provide. After passing through the impellers, the water will exit the pump through the delivery outlet. A hose/pipe can be connected to the delivery outlet, through which water can be pumped under high pressure.

The selection of a borehole pump depends on your situation, and is based on the following variables: How wide is the passage to/in the well? How deep will the pump be immersed? How much flow rate and pressure do you require? For answers, please refer to our pump configurator (blue bar), and we will then suggest one or several borehole pumps that may be suitable.

Borehole pump with booster

A borehole pump with booster, also known as an underwater booster pump, is used mainly in rainwater harvesting systems to recycle water: for example, to flush a toilet or to supply water to a washbasin, a washing machine, or a dishwasher. In these situations, this type of pump is the most practical solution because it can be installed 'invisibly': namely, in the well. This will save a great deal of space. In addition, the pump's noise level will be very low because it is positioned under water. Furthermore, the borehole pump with booster is activated/deactivated automatically depending on the water requirement. When a washbasin tap is opened, the borehole pump switches on automatically, and switches off when it is closed again. We supply the following borehole pumps: the DAB Divertron series, the Tallas D-ESUB, the DAB Kit Pulsar Dry, and the EJ6 Plus.

Borehole pump with speed controller

Ideally, a borehole pump with speed controller is used for larger irrigation systems. The speed controller (e.g. the DAB Active Driver) controls the pump, allowing it to increase and decrease its speed gradually, until the required RPM has been reached. This is particularly important with regard to the larger irrigation systems, because without a speed controller the pump would consume several kilowatts all at once, which would significantly reduce its lifespan. We therefore advise that you always equip heavier borehole pumps with a speed controller. Furthermore, this combination pump is also ideal for irrigation with different sprinkler groups, because it is able to provide each group with a pre-set pressure level, and will increase and decrease its RPM speed automatically to achieve this.

Suction depth and noise level

Draining water

The water is pumped via the booster pump's delivery connection and the connected discharge hose/pipe to one or more irrigators/sprinklers/draw-off points. In this respect it would be wise to use a hose with an inside diameter of 25 mm or more, because a smaller diameter will cause considerable pipe resistance. As a result, the pump will be unable to meet its specified capacity and pressure.

Active system

The garden pump starts pumping immediately when its plug is inserted into the wall socket, and stops when the plug is removed. For some applications, manual operation is not desirable: for example, when supplying:

• toilets, washbasins, washing machines

• an outside tap

• a hand-held sprayer/high-pressure sprayer

In these situations it is desirable that the pump responds automatically to the water requirement. For example, if you want to wash your hands, active systems such as the Electric Control System and the DAB Control-D ensure that water is instantly supplied. These systems respond to water requirement: If a tap is opened, pressure will drop and the pump has to be activated to supply water, and it switches off automatically when the tap is closed. This enables you to turn a borehole pump into an active device.