The Best Magnetic Filter For Central Heating

The purpose of a central heating magnetic filter is to capture any contaminants before they reach the boiler. This helps to extend the life of the boiler as well as improve its energy efficiency in the long run.

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Magnetic filters are a great addition to any central heating as they help to keep the system clean as well as reducing energy and maintenance bills. They are installed on the pipe that returns the water to the boiler and the magnets attract contaminants before its passed back to the boiler.

The best magnetic filter for central heating is the MagnaClean System Cleaner, which has a twin reverse flow and improved valves for superior cleaning.

Central Heating Filter Comparison

Central Heating FilterDiameter
MagnaClean Professional 222 mm
Fernox TF122 mm
Boilermag Domestic22 mm
Worcester Greenstar Central22 or 28 mm
Altecnic Dirtmag IQ22 mm
Boiler-m8 Defender22 mm

During new boiler installations, most people will also install a new magnetic filter. The filters are designed to be replaced easily and most brands will recommend changing the filter annually. As an added bonus, some boiler brands offer extended warranties for those that install a filter to their system.

Below is a list of the best magnetic central heating filters that are easy to install and maximize debris capture.

The Best Magnetic Filter For Central Heating

1. Magnaclean Professional 2 Magnetic Filter

Magnaclean System Cleaner
The MagnaClean Professional 2 is a popular central heating filter that has a compact design for tight installation spaces. The brand claim that due to its versatile design, you are able to install the system cleaner in just 2 minutes.

Included in the box is the filter, isolate valve fitting, lid and valve spanner, installation guide, warranty card and labels.

Other features of the MagnaClean Professional 2 include:

  • Low profile drain valve
  • Twin reverse flow for maximum debris capture
  • In-line installation takes just 2 minutes
  • Suitable for all boiler types
  • 22 mm diameter
  • Stainless steel housing

The MagnaClean Professional 2 is the complete package and the most popular choice in the UK. It will provide impressive results by capturing sludge and large iron particles for years to come.

MagnaClean now offer the Professional 3 model, which performs the same but has the inclusion of WiFi, which allows remote viewing of the heating system.
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2. Fernox TF1 Central Heating Magnetic Filter

Fernox TF1 Central Heating Magnetic Filter
Another popular magnetic filter for central heating systems is the Fernox TF1. The brand state that it’s a “revolutionary” hydro-cyclonic and magnetic inline filter, which uses a unique action to remove all contaminants.

Unlike many of the alternatives, this magnetic filter doesn’t need to be removed or disassembled for cleaning. This means that it can take just seconds to clean the filter for maximum cleaning power each and every time.

Other features of the Fernox TF1 include:

  • 22 mm diameter
  • Remove both magnetic and non-magnetic debris
  • Fits vertical or horizontal pipework
  • Easy accessible dosing point
  • Cleans in seconds without the need to remove it
  • Includes valve fittings, rubber washers, instructions and labels

The Fernox TF1 is a highly rated magnetic filter that is suitable for the majority of boiler systems. It also has the benefit of being able to be installed either horizontally or vertically, which may be a requirement for certain installs.
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3. Boilermag Domestic Heating System Filter

Boilermag 22 mm Domestic Heating System Filter
The Boilermag is a more affordable option that is able to extract both magnetic and non-magnetic debris. As with the Fernox TF1, you are able to install the filter at any angle, which makes installation to the pipework far simpler.

Compared to similar priced filters, this magnetic filter comes with an impressive three year warranty for peace of mind.

Other features of the Boilermag Filter include:

  • Fits any angle pipework
  • No block design
  • Includes a three year warranty
  • Extracts both magnetic and non-magnetic debris
  • Everything you need in the box

Included in the box is the filter, brass isolation valves, valve seats, bowl spanner, pipe cut template, magnetic core remover, security seals and labels. It’s the complete central heating filter package that meets all the latest UK standards and won’t disappoint.

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4. Worcester Greenstar Central Heating System Filter

Worcester Greenstar Central Heating System Filter
Worcester Bosch are one of the best boiler brands in the UK but are known for their premium price tags. This filter is no different and is by far the most expensive within this article. Unlike any of the alternatives listed within this article, it’s also available with a 28 mm diameter.

In order to improve the ease of servicing the filter, it has a one-way valve for adding system chemicals and a completely detachable body.

Other features of the Worcester Bosch Greenstar include:

  • Available as a 22 or 28 mm diameter
  • Meets the GASTEC standards
  • Captures magnetic and non-magnetic contaminants
  • Easy access drainage point
  • Detachable body for easy servicing
  • Can be installed under or over the boiler
  • Includes a 12 month warranty

Although expensive, the Worcester Bosch Greenstar is a highly rated central heating filter that will increase the comfort and efficiency of your system. It has a well-thought out design that helps to improve the ease of servicing, which makes it worth spending the extra.

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5. Altecnic Dirtmag IQ Magnetic Sludge Filter

Altecnic Dirtmag IQ 22mm Boiler Protect Clean Magnetic Sludge Filter
The Altecnic Dirtmag IQ is an affordable magnetic filter that is able to capture both magnetic and non-magnetic dirt. Compared to similar priced filters, this has far superior build quality with a high density polyethylene internal filter and neodymium magnets.

Other features of the Altecnic Dirtmag IQ include:

  • Triple separation action
  • Fits vertical or horizontal pipework
  • Chamber is manufactured from glass fibre polyamide 66
  • Built-in air valve that vents out any air in the system
  • Servicing doesn’t require isolation
  • Includes a two year guarantee

The Altecnic Dirtmag IQ is an excellent all-round option that combines build quality with value for the money. It also has unique features such as a built-in air valve, triple separation and other features that make it standout from the crowd.

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6. Boiler-m8 Defender Magnetic Filter

Boiler-m8 Defender-2 22mm Central Heating Magnetic System Boiler Filter
The Boiler-m8 Defender is a guaranteed replacement magnetic filter that is CE approved and comes with a two year extended warranty. Although it’s the cheapest within this article, this model is constructed of a premium stainless steel filtration and includes high powered magnets for capturing the debris.

Other features of the Boiler-m8 Defender include:

  • 22 mm diameter
  • Constructed of high powered magnets and a stainless steel filtration
  • Removes both magnetic and non-magnetic debris
  • Easy to service and maintain
  • Manual air vent but available with an automatic
  • Includes a 2 year warranty
  • CE approved

If you require a cheap magnetic filter for your central heating system that is actually worthwhile, the boiler-m9 Defender is the best option. It’s built to the high standards you would expect from the premium alternatives and backed by a two year warranty for peace of mind.

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If you are installing a new boiler in your home, a magnetic filter is an optional component that will pay for itself in the long run. As mentioned by Viessmann, your boiler warranty may even be affected if a filter isn’t used.

All of our recommendations are suited to a range of budgets and will instantly help capture contaminants in the system. To avoid disappointment, we recommend that you buy from reputable brands.

The Author Who Worked On This Article

author dan darimo

Dan Morgan

As a keen DIY’er, gardener and somebody that loves the latest tech, Dan is someone that brings years of experience in multiple trades. Since buying his first house, he has been obsessed with renovating properties and filling it with the latest products. This has led him down the road of testing hundreds of products and creating in-depth “how-to” and informative guides that offer his first-hand experience. Other interests include working on cars, keeping fit through sports or his home gym, caravanning and drinking great coffee.

If you would like to read more about Darimo and the authors, you can visit our about page. This goes into great detail regarding how we test products, create our guides and everything else.

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