Whether you're looking for a garden pump, domestic water system, submersible pump or petrol-powered water pump, we have got the right pump for any application. Einhell water pump guide
What to look out for when buying a water pump
Depending on the application, there are different types of water pumps on the market. Factors such as flow rate and discharge head play a role, but so does the type of water to be pumped. If you want to pump out wastewater, you should consider the presence of particles such as sand, mud and stones in the water. Here we have put together a brief overview of the most important aspects when it comes to water pumps.
Surface vs. submersible pumps
The biggest distinction between different types of water pumps can be made based on where they are used: Pumps that are placed in the water in order to pump it out are called submersible pumps. Pumps that are used out of the water, e.g. in your garden, and move water from a reservoir by means of a hose, come under the general category of surface pumps. The terms "suction head" and "immersion depth" are important for the operation of your pump. With surface pumps, we talk about suction head or, in other words, the maximum difference in height (say 8 meters, for example) between the surface of the water and the inlet of the garden pump. For submersible pumps, we refer to immersion depth. This indicates the maximum possible difference in height between the surface of the water and the pump at the bottom of your swimming pool, pond, etc. Einhell submersible pumps have maximum immersion depth of up to 20 metres, depending on the model. In short, the difference is that surface pumps generate more pressure and thus transport the water with larger discharge heads of up to 50 meters. The main strength of submersible pumps, on the other hand, is their high flow rates, meaning they can pump many litres of water per hour.
Output
The most important technical characteristics of a water pump are its flow rate and its discharge head. These tell you how much water the pump can move and what height difference it can handle. The flow rate indicates how much liquid a pump can displace over a certain period of time, and is usually given in litres per hour. The discharge head is the maximum height (usually in meters) over which the water can be pumped. The discharge head and discharge pressure are always directly related: The higher the head, the higher the pressure must be to pump the water over the required height. If the height is, for example, 37 meters, it must be pumped with a discharge pressure of 3.7 bar. At 10 meters, 1 bar is sufficient.
Clear and dirty water
For submersible pumps, it is particularly important to distinguish between pumps designed for clear water and dirty water. The term dirty water covers any water that has been contaminated by consumption, i.e. is no longer clear. Water which contains solids such as sand, soil or leaves is also classified as dirty water. In such cases, different sizes of dirt particles can be present. We then refer the grain size, or foreign body size. Drinking water, or clear water, in contrast to dirty water, refers to water that has not been used and is considered clean. In the garden, this might include pool water, well water and rainwater collected in rain barrels or cisterns, for example.
Switching technology
Depending on the type of pump, there are different times and different ways in which the pump starts up. Submersible pumps usually have an internal or external float switch or an AquaSensor. This switch or sensor enables the pump to detect the water level and automatically switch itself on and off, according to the limits that have been set for suction head and start level. Surface pumps that are outside of the water, such as garden pumps or domestic water systems, are equipped with either an on/off switch or a pressure switch that automatically detects when water is requested and switches the pump on accordingly. Submersible pressure pumps and deep well pumps also use pressure switches.
