Category - Boilers
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Will Scholfield, Engineer

31 Jan : Updated 19 Apr ● 6 min read

Are magnetic filters worth it? Boiler filters and limescale inhibitors explained

Keeping your central heating system working effectively is crucial to a properly heated home. You may not know it, but your system will gradually build up with debris, rust, and unwanted materials over time - creating a sludge-like substance. To prevent a breakdown, you need to look after your system and clean it regularly to keep it running like clockwork. Magnetic filters and limescale inhibitors are a good way to do it.

Are magnetic filters worth it? What is a limescale inhibitor? This guide will explain some of the best ways to clean your system and how you can do it safely and effectively.

What is a magnetic boiler filter?

A magnetic boiler filter is an attachment which is fitted to your central heating system. The filter will be fitted on the pipe that returns water to your boiler, which will prevent unwanted waste materials from entering the system.

Magnetic filters for central heating systems attract metallic particles and store them away from your system. This will also stop them from disrupting the flow of water, as well as stopping them from eventually turning into a sludge-like substance.

How can I get a magnetic filter installed?

Magnetic system filters are relatively easy to install, but if you’re not comfortable with the process, a professional can give you help and advice. It’s good to know that our engineers install a filter with every new Worcester Bosch boiler & Ideal boiler at no additional cost.

An engineer will usually go through the following steps to install magnetic filters for combi boilers:

  • Firstly, they’ll drain the central heating system of water.
  • The pipe will then be marked to show where the magnetic filter will sit. There are different sizes of filter which may require more or less pipework.
  • The unneeded pipe will be cut away to make room for the filter.
  • When the pipe has been removed, the valves will be placed on each open end of the pipe.
  • The filter can then be placed between the valves and connected securely.
  • You may need to re-pressurise your system afterwards.

Most of the time, filters are added to a heating system during the boiler installation process. You can also have one added to an existing boiler if you wish and if it is appropriate, but it’s worth having your boiler checked first. You don’t want to install your filter after you realise you’re desperately in need of a new boiler.

The benefits of magnetic central heating filters.

Having magnetic filters for central heating systems has a long list of benefits. The main benefit, of course, is its ability to help your system run effectively and efficiently due to the removal of debris and unwanted waste materials. Because of the efficiency, you’ll also find your energy bills to be much lower than if your system was struggling to function properly. Moreover, in the future, when sludge does build, you'll only need to clean the filter rather than the entire boiler system - which makes the job so much easier. Check out our guide on how to clean a magnetic filter for more information.

With a magnetic filter, you’ll reduce the risk of needing expensive repairs later down the line. It will prolong the life of your boiler and can even increase the length of your boiler warranty in some cases. 

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What is limescale inhibitor?

A limescale inhibitor is a chemical liquid that prevents limescale from forming inside your central heating system and its pipes. Without limescale central heating inhibitor, the limescale will stop the heat exchangers from working properly. The inhibitor will prevent the build-up of sludge before it begins.

How do I run the limescale inhibitor through the system?

Central heating inhibitor can be added to your system in a number of ways depending on the system you have:

  • Directly into your radiators.
  • In the loft tank.
  • Into the magnetic filter.

See our central heating inhibitor guide for how to add inhibitor to your system. You can find limescale inhibitors test reports and reviews online to see which will work better for your system. If you’re still stuck, talk to an engineer using our live chat and we’ll help you as much as we can.

The advantages of a limescale inhibitor.

A limescale inhibitor will effectively cut through the dirt and grime which builds up inside your system. It’ll help the water flow at a better rate, increasing the life of your system, efficiency, and its components.

A huge benefit is that overall, it will save you money. From the price of the inhibitor, you’ll be saving money on boiler system repairs or replacement parts when the limescale and sludge builds up. After inserting it into your system, it will also need no maintenance as your system will work the inhibitor around itself effectively.

Do I need a magnetic filter and limescale inhibitor?

Yes. If you have a new boiler or plan on getting one, you should look to have a magnetic filter fitted and a limescale inhibitor put through your system. This will ensure that from day one, you’re looking after your boiler and making the running of it more efficient.

How to spot the signs.

We’d recommend a filter and inhibitor on all central heating systems. This increases their lifespan and will save you from constantly spending money on repairs and new parts. If you don’t have either just yet or your boiler is showing signs of the following:

  • Your boiler is leaking.
  • Your radiators are cooler at the bottom.
  • Your boiler always seems to struggle when reaching the desired temperature.
  • Your pumps fail.
  • You find sludge and debris in broken boiler parts.

If you have any of these problems, then it’s only a matter of time until your boiler or multiple components inside break down and need replacing. To prevent this from happening, a magnetic filter and limescale inhibitor can help to keep things running.

So, are magnetic filters worth it? Talk to our BOXT engineers.

Magnetic boiler filters and limescale inhibitors will certainly add a few more years to the life of your boiler and central heating system. If you have any questions about the process or how you can improve the life of your boiler, you can chat with us online using BOXT’s live chat.

If your boiler breaks or it’s starting to show signs of wear and tear, we’d always recommend a complete brand-new boiler replacement. You can find your ideal boiler on our website by using our ‘Find A Boiler’ tool, created by our boiler experts.