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What are magnetic heating filters for?

Magnetic filters are the most effective protection of heating systems against damage caused by mechanical impurities. Dirt reduces the system's performance, increases energy consumption, damages system components and shortens their lifespan. Cost of a magnetic filter is therefore negligible compared to the financial savings in the long run.

Where are magnetic filters used?

Magnetic filters are an innovative liquid filtration system in heating systems. In new low-energy buildings, they are already a standard part of the equipment, but their installation is also recommended in older family houses. For a relatively low price, you will get significant savings - you will save mainly on heating costs, but also on maintenance and servicing of individual components of the heating system.

In new systems, or when replacing key components (boiler, circulation pump), using a magnetic filter is strongly recommended. In order to save energy, modern boilers and pumps use magnetic inserts, but metallic impurities from the operating fluid settle on them. Of course, accumulated dirt leads to clogging, seizing and other pump malfunctions. Therefore, some boiler manufacturers even offer an extended warranty if you equip your heating system with a magnetic filter.

In modern heating systems a magnetic filter is essential.

Risks of dirty water in your heating system

The unfiltered heating liquid contains a number of solid particles – particles of magnetite, loose metal fragments and other tiny impurities. The system is closed, so that liquid is never replaced here and the amount of released particles constantly increases. This pollution damages your heating system and reduces its efficiency.

  1. Mechanical particles clog the components of the heating system, especially circulation pumps and boilers. These components are very susceptible to damage by polluted water - there is wear of the material, more frequent breakdowns and even pump seizing or clogging.

  2. Fine particles settle on the inner walls of pipes and heating components, reducing the efficiency of heat exchange. Much more energy will be used to achieve the desired heating performance with a heating system clogged in this way.

Water filtration saves money for energy and service, but also time spent on repeated maintenance of the system.

How magnetic filters work?

A big advantage of a magnetic filter is the fact that it does not need energy to operate - it works only on the basis of physical laws. As the name suggests, the basic component of it is a strong magnet that captures magnetic particles in the heating system as tt is magnetic particles that make up most of the impurities in the heating system.

In addition, some magnetic filters are fitted with a so-called air separator. Efficiency of this kind of filtration is almost one hundred percent and removal of all kinds of impurities is ensured. And heating is automatically vented, which brings further savings, as air in the heating system also reduces its efficiency and speeds up corrosion of metal components.

A magnetic filter muset be installed on a return pipe of the heating system, preferably before a pump and a boiler, as these devices contain moving parts that are most sensitive to mechanical pollution. All water in the heating system will therefore flow through the filter, where filtration itself takes place. Filters work continuously and filtration is repeated, so there is no risk of re-contamination of the heating liquid.

​Step-by-step filtration process

Let's take a closer look at what happens to the dirty water in a magnetic filter. For combined heating filter, which, in addition to a magnet, is also fitted with an air separator, filtration takes place as follows:

  1. Water from the pipes flows into the filter tank with an integrated magnetic rod, on which all magnetic particles are captured. Some filters have a magnetic ring located outside the tank instead of a rod.
  2. At the same time, unwanted bubbles float to the surface in the tank, which causes air separation. The filter lets this excess air out.
  3. Completely clean and deaerated water flows from the filter back into the heating system.

Flamco combined air and dirt separator. 

The core of a correct function of a magnetic filter is its maintenance

Magnetic filters always work, so their maintenance is even more important. It is usually necessary to clean the filter from trapped dirt once a year. However, cleaning is necessary even after a few days after its first usage as the filter suddenly catches all the dirt already accumulated in your system possibly over several years. Modern magnetic filters enable maintenance in full operation, i.e. without the need to shut down the system or dismantle the filter. In addition, you can do the entire cleaning yourself in a few minutes.

The cleaning process is determined by the manufacturer, so follow instructions in the guide. However, it is usually necessary to remove the magnetic rod (simply unscrew it), which will release the trapped particles from the magnet into the water in the tank. This water, together with impurities, is then allowed to flow out through the drain valve into the prepared container.

The magnetic filter is a cheap, universal and virtually 100% effective solution for maintenance of heating systems. Choose from our range of magnetic filters and save on heating.