When you need to buy a water pump, it is recommendable to research the different types of water pumps. There are a lot of different types of water pumps and they are all used in different occasions. Luckily, they are not all that different, because you can divide them into three main categories. These categories will help you choose the right water pump for the job. The three categories are: centrifugal pumps, self-priming pumps and underwater pumps.
Lets start with the centrifugal pumps. These pumps are usually used for small suctions heights, because centrifugal pumps have less suction power than self-priming pumps and underwater pumps. Therefore, they also have to be started manually. These pumps are placed outside of the water, but you do place the end of the suction hose in the water (or other source). The suction force is to weak to suck the water up by itself, so it is mostly used in situations where the water is already fed to the pump.
The next category is the self priming pump. These types of pumps use impellers to suck up the water. The suction force is created by using multiple impellers. These impellers rotate and this allows the pump to suck up the water. This can be done at a maximum of 8 metres. The more impellers the pump uses, the greater the power is. Pumps that fall into this category are the booster pump, the rainwater harvesting pump and the irrigation pump.
The last category is the underwater pump. On the contrary to the centrifugal pump and the self-priming pump, this type of pump is used completely under water. An example of an underwater pump is a submersible pump. This type of pump also uses impellers, specifically open impellers. These make sure that the water can reach the pump easily.