A shower pump provides a boost to the flow of water
A shower pump is an excellent solution if you are experiencing a weak flow of water in the shower or when you wash your hands. The pump gives the water a boost, creating a true power shower. Power shower pumps are available in a wide range of models and sizes, and include positive, negative, and universal head shower pumps. In addition, you can choose a pump that has one impeller or two, and there is also a difference between centrifugal and regenerative pumps. The pump that is the best option in your situation depends on certain specifications. Here we explain what you should take into account when selecting a suitable shower booster pump.
If you do not have a cold water storage tank in the attic, under no circumstances should you connect a shower pump directly to the water mains system. This is prohibited by law in the UK. A break tank should be used at all times. Otherwise, there is a risk that the pump will drain the water mains network (before it enters your house) and will cause your neighbours’ water pressure to drop.
Cause of low water pressure
Many old houses make use of a gravity-fed system, in which the water source (for example a cold and hot water tank) is situated higher than the point at which water is supplied (e.g. a shower). The difference in height will create pressure, and the greater the difference, the greater the pressure. In most cases, the difference in height varies from three to four metres. In many homes, the water pressure in a gravity-fed system is low. Residents looking for a way to increase the water pressure therefore decide to purchase a shower pump.
Another reason for low water pressure may be that the pressure throughout the neighbourhood is low, which occurs more frequently in mountainous areas. Although water-supply companies try to provide a minimum pressure of 14 PSI, which equals 1 bar, in reality, this is not always feasible.
How a shower pump works
In the UK, many households use a water pump for standard and electric showers, which are not directly connected to the water mains system. A shower pump is installed between the pipes, and the water enters the cold water tank via the main pipeline. From there it either flows into the hot water tank, where it is heated, or from the cold water tank directly into the pump. In the pump, the water pressure is boosted and, depending on the pump you select, increased by up to 3 bar.
The pump switches on and off depending on the pressure difference in the pipes. When a tap is turned on, the pressure in the pipe will drop and the pump is activated. It switches off again when the tap is turned off and normal pressure has been restored.
A positive, a negative, or a universal head shower pump?
To select a shower power booster appropriate for your situation, it is important to know what system is used in your home. To determine whether you have a positive head or a negative head system, you can measure the difference in height between the water tank and the place where the water needs to be transported, such as the bathroom.
Positive head shower pump
With a positive head system, the water flows to the shower head in a natural manner (owing to gravity when there is a height difference). In that case, the shower is situated at least 60 cm below the water tank. If you want higher water pressure in this situation, you will need a positive head shower pump, which is activated as soon as the water runs into it, where it is then boosted. The water needs to enter the pump at a minimum flow rate of 0.6 litres a minute in order for it to switch on. You can easily measure this yourself by collecting the water in a bucket or other container. After a minute, check how much water is in there.
Negative head shower pump
If the water pipes in your bathroom are situated at the same level, higher, or no more than 60 cm below your water tank, the water will not flow automatically or quickly enough to your sanitary appliances. In that case you need a negative head shower pump to give the water a boost. The pump draws in the water and then increases the water pressure.
Universal head shower pump
A universal head shower pump is used in situations in with negative head, although it is suitable for positive as well as negative head systems. With this pump, it does not matter whether or not the water flows naturally from the outlet under gravity.
Single or twin impeller shower pump?
Whether you need a shower pressure booster with one or two impellers depends on whether the water pressure is low in either the cold-water pipe or the hot-water pipe or in both.
Single impeller shower pump
A single impeller shower pump can only be connected to one pipe. This means that you can transport only cold water or only hot water with this pump. A single impeller pomp is often used with an electric shower, as only the cold-water pipe is used. The pump is placed between the pipes, and pumps the water to your electric shower, where it is then heated in a box containing a heating element, resulting in instant hot water.
In some situations, an electric shower is connected to the water mains system, but then a break tank has to be installed between the pipes so that the pump takes water from this tank and not directly from the water main.
Twin impeller shower pump
You need a twin impeller shower pump if you want to increase the water pressure in both the cold-water and the hot-water pipes. This pump has a connection for each pipe and can transport hot and cold water at the same time. This is an excellent pump, for example, for a general or thermostatic mixer shower, where the water from both pipes is combined within the mixer unit.
Shower pump for a combi boiler
A shower pump can only be used in combination with a combi boiler if a break tank is installed between the boiler and the pump. It is mandatory to use one, because a combi boiler gets its water directly from the water mains system. Installing a pump in between means that it draws in so much water that the pressure in the general water network would be reduced.
In practice, however, it rarely happens that a break tank is installed with a shower pump. Because such tanks need to store a large amount of water, they would take up a lot of space. It would be an enormous investment just to increase the water pressure in the bathroom. In this case, it might be worth installing a booster pump in order to increase the water pressure throughout the house. This can be done with a DAB Esybox or a DAB Esybox Mini 3.
Pipe diameter
The pump pushes the water through the pipes with considerable force. Therefore, it is important to select the right pump in line with the pipe diameter size. The larger the diameter, the more water can flow through it at a given time. Selecting the right pump will improve the water pressure. In the UK, the standard pipe diameter is 22 mm. If you have a smaller diameter, you will need a less powerful pump.
Increase pressure throughout the house
A DAB Esybox or an Esybox Mini 3 is an excellent solution if you are looking for a pump that is suitable to increase pressure in the entire house. This booster pump is placed between your water pipes and can supply water to different applications at the same time. For instance, you can take a shower while both the washing machine and the dish washer are running. Even if you were to turn on all the taps in the house, there would be hardly any difference in the water pressure.
The pump is fitted with a variable speed controller, which ensures that it will run only at the rotational speed required at that moment. As a result, the pump will consume more energy if many applications need water at the same time but consume very little if only one tap is turned on. This will save you a considerable amount of money each year.
The DAB Esybox Mini 3 also has a Power Shower feature that can be activated easily via a mobile app. It will provide an even more powerful water jet when you are having a shower.
Again, it is not permitted to connect the pump directly to the water mains system. Therefore, make sure you install a break tank if you do not have a water storage tank.
