System Protection Filters


Over the last ten or so years, boilers internal workings have become a lot smaller inside, and there's more of them. The main reason is for transfer of heat, conversion of energy from gas to water. You can have lots of smaller pipes to give you more surface area, as opposed to having one large pipe running over the burners.

As a downside however, boilers are a lot more susceptible to becoming partially blocked, which means we get lots of performance problems. More components also rely on rubber o-rings and plastic fittings to make the water tight seals. But if we get the rubber and plastics dirty with bits of iron oxide (bits of radiator flakings from inside your system), we increase the potential leaks occurring. So, what can we do early enough to stop potential problems? Please read on.


When to Install Them


If the system is too dirty, we need to Powerflush the system first before we install a filter. The reason being, some dirt may have become loose, and then formed in clumps somewhere, creating a potential blockage. A system protection filter has the system water flowing through it, and will only remove the particles in suspension in the water, not those already deposited.

Filters are best fitted; after a powerflush, on new installs, and also if we are sure the water is not past the point of requiring a powerflush. Many boiler manufacturers now recommend the inclusion of a system protection filter in their installation instructions. If the boiler manufacturers recommend them, they are generally a good thing. And they are proven to work. The majority of central heating and boiler breakdowns are due to the dirty gooey water in the system, so it makes sense to invest in a little protection for your expensive boiler purchase.

You can install a filter if you can manage a bit of basic plumbing, you do not have to be gas safe registered. However, these jobs are always best left to a competent installer such as a plumber or heating engineer.

Magnaclean Filter

As always, when refilling, please make sure your system corrosion inhibitor is replaced.


There are several filters available, and they all claim to do their own thing, ultimately they all work to try and remove the deposits in the system. The top three out there now in no particular order are; Adey Magnaclean, Spirotrap Magnabooster, and the Fernox Total Filter.

There is normally a magnet incorporated somewhere in the filter, as the majority of debris is metallic, so will stick inside the filter. Some also have a mesh, to get the non magnetic stuff. Some are made of plastic so will be vunerable if you accidentally knock them. Some you can clean yourself without too much fuss, however some are not so easy. If you do decide to upgrade to a filter to protect your boiler and system, please check the manufacturers website for a quick overview of their product before you buy! Also check the warranty the manufacturers give, this can sometimes be a measure of how much they trust their own products!

Spirotrap Magnabooster Under Boiler



Not to be Confused


Please note, some consumers can get confused with the difference between water hardness, and dirt in central heating systems. The water which comes from your taps is not what these filters are for, these filters protect the water circulating around the central heating circuit and boiler. Limescale coming from your taps is a separate issue, and there are other solutions available to try and overcome water hardness.