Connect a sand filter system


Sand filters are very efficient filters, but due to some extended possibilities they are a bit more difficult to connect than conventional filters like filter cartridges. The following guide should give you tips on how to connect a sand filter system and what to take care of when starting up.

Possible applications for sand filter systems

The application fields for sand filters are widely spread. Therefore, a relatively large number of people can come into contact with it:

  • Sand filter for wells
  • Sand filter for pools
  • Sand filter for ponds
  • Sand filter for aquariums
  • Sand filter for other water tanks, basins and reservoirs

Operation of sand filters

However, the operation of sand filters differs significantly from other filters. While the often found paper or mat filter must have the largest possible surface area for the fluid to be filtered, the filtering is carried out during the seepage through the sand filter.

Mechanical and biological filtration

Thus, the rule is that less the size of the surface as much as the height of the sand layer is crucial. It is thus mechanically filtered throughout the passage. In addition, there is an oxygen-free, anaerobic zone inside. This is where bacteria settle, which also take on biological filtering.

Determining the degree of contamination

Due to the density of dirt in the filter sand, the medium to be filtered will seep through quickly or slowly. So, when the system is closed, it can be determined how far the pollution level has progressed. By changing the flow direction, the dirt can then be flushed out of the sand and into a wastewater connection.

Connection options of a Sanfilteranlage

Of course this requires a lot of connections to the sand filter system. Accordingly, sand filter systems are also equipped with a four-way valve or a six-way valve. This allows the following tasks to be set:

  • circulate for cleaning to and from the pool (pool, aquarium, pond)
  • Close all connections for pressure build-up
  • Reverse the flushing direction to the sand filter backwash with simultaneous opening of the sewer connection
  • possibly extended circulation through a heating valve

Connection paths within a sand filter system

It can be present on a sand filter so different connections. First, the most important elements of the system must be determined:

  • from the pool to the multiway valve
  • from the multiway valve to the pump
  • from the multiway valve to the filter vessel
  • from the multi-way valve to the wastewater connection
  • from the reusable valve back to the water basin
  • possibly from the multi-way valve to the heating valve
  • from the pump to the multiway valve (to close the pump circuit)
  • from the filter boiler to the multiway valve

Connection sizes and main components

So there are always also inflows and outflows. The connections are usually provided in sand filters in 1 ½ inch. While the pump, filter bowl and multi-way valve are already connected to each other in a completely acquired sand filter system, you still have to make the remaining connections:

  • Inlet and outlet to the water basin (between water basin and multi-way valve)
  • Wastewater connection at the multi-way valve
  • optional connection for a heating valve

Before putting into operation: observe the pumping directions

On the other hand, if you buy all the components individually or build your own sand filter system, the other connections must also be made. Always consider the circulation or pumping direction of the water.

Sand in the pool can mean a wrong connection

Otherwise, you may get sand from the sand filter system in the pool or the corresponding pool. For a purchased complete system, you should always follow the assembly instructions of the manufacturer.

Tips & Tricks

In order to be able to better understand the function of sand filter systems, we also offer a detailed series on these filter systems in the house journal. For example, you will learn more about basic questions under "Structure and materials of sand filter systems".


Video Board: How To: Install a Top Mount Pool Sand Filter