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Your boiler is at the heart of your home central heating system. It keeps you warm with hot water circulating in your radiators. But things can go wrong in the central heating system with the passage of time.
Rust and sludge inside the radiators and the pipes can clog the flow of the water. This can cause your heating system to work inefficiently and can cause costly boiler repairs. A magnetic filter is a device designed to protect your boiler system from these issues.
How Does a Magnetic Boiler Filter Work?
A magnetic filter is an attachment fitted to your boiler pipework. It is usually placed on the return pipe, where water flows back into the boiler. The filter contains a powerful magnet. As the water passes through, it attracts and captures metal particles such as rust.
These particles are the main cause of sludge in your central heating system. By holding onto the sludge, the magnetic system filter stops it from moving further into your boiler and radiators.
This filter work helps keep the water flow smooth. Without the magnet filter, the sludge will accumulate and clog pipes, damaging your pumps and valves. This can, in the long run, decrease the lifespan of your boiler. A filter prevents damage and expensive repairs to your heating system.
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Pros of a Magnetic Boiler Filter
- Protects your boiler: Prevents the sludge and rust that can destroy major components in your boiler system.
- Improves efficiency: Clean water flow means your central heating system works better.
- Reduces electricity bills: A high-efficiency system will burn fewer energy units to heat your home.
- Extends lifespan: It keeps your boiler and radiators serviceable for longer.
- Supports warranties: Most new boiler installations demand a filter in situ for protection.
- Simple maintenance: Easy to clean a magnetic filter during a boiler service.
Cons of a Magnetic Boiler Filter
- Not a complete fix: A filter doesn’t stop limescale, so many homes use magnetic filters and limescale inhibitors together.
- Needs cleaning: You must clean the filter during your annual boiler service.
- Upfront cost: Buying and fitting a magnetic filter adds to boiler installations.
- Not always necessary: Some small systems may not need a magnetic boiler filter, though most heating engineers recommend one.
How to Clean a Magnetic Boiler Filter
It is an easy job, but it should be done by a heating engineer or a plumber with the right qualifications. A Gas Safe-registered heater will take out the magnet during your annual furnace maintenance. The filthy sludge is at that time washed away.
This keeps the filter working well. This is better left untried without proper training. It is usually enough to require this cleaning every year, though some homes that have older systems will need more frequent cleaning.
Maintenance Tips for a Magnetic System Filter
- Always schedule a yearly boiler inspection with a Gas Safe-registered fitter.
- Ask your heating engineer to clean the filter as well.
- Use a central heating inhibitor with the filter to reduce the formation of sludge.
- The reason is that very outdated systems might need a power flush before the installation of a magnetic filter.
- Keep track of services and filter cleaning as proof for warranties.
Boiler Magnetic Filter Cost
The cost of a magnetic boiler filter depends on the brand and your system size. In the UK, a filter will be around £80-£150. Improved versions will be costly, but they will hold more dirt before you need to rinse them.
Boiler Magnetic Filter Installation Cost
To install a magnetic boiler filter, you need a qualified heating engineer or a Gas Safe Engineer. It can be fitted during new boiler installations or added to an existing system. If fitted during the boiler installation, it is usually cheaper.
- Cost when added with a new boiler: £100–£200, including fitting.
- Cost when added to an existing system: £150–£300 including fitting.
The price depends on your site and the engineers’ rates. Always consult a plumbing or heating engineer to be sure of the cost.
Are Magnetic Filters Mandatory for a Combi Boiler?
It is not legally mandatory to install a magnetic filter for a combi boiler. However, many boiler makers now require a filter fitted for warranty cover. A gas safe registered engineer will usually recommend one when a new boiler is installed.
Unfiltered, the grime from the central heating can build up and make your boiler last fewer years, costing more in terms of repairs. For the average home, we would advise having a magnetic filter fitted as a precaution on your boiler and central heating system.
Are Magnetic Filters Worth It?
For most households, magnetic filters are usually worth the cost. The central heating system without the filter will be full of sludge which will cause expensive repairs and shorten the life of your boiler. When you have a filter in your boiler and radiators, it allows your heating system to function properly. It’s a small expense that saves you a huge amount over time.
Final Thoughts
In conclusion, a magnetic filter is a tiny gadget but its impact on your boiler and heating system is huge. It acts as a trap for dirt, enhances the water flow, and lightens the boiler load. You will not only save money on your bill but also avoid expensive repairs for your boiler. In case you are installing a new boiler or you wish to have a filter on your existing system, a magnetic filter is an intelligent choice.
Always have a gas safe registered installer fit a magnetic filter, regularly clean the filter, and consult your heating engineer about the best recommendations. In brief, fitting a magnetic filter is one of the best things you can do to maintain your boiler in good condition and get the best out of your home heating.
Frequently Asked Questions
The magnetic filter collects rust and grime in your central heating. It prevents clogging, guards your boiler, and facilitates better heating efficiency.
It is not technically required, but many manufacturers will advise you to do so. It can maintain your warranty in force and extend the life of your boiler.
The cost ranges from £80 to £150. Installation by a Gas Safe-registered engineer will cost £120–£300, depending on whether you want to install a new system or upgrade an existing system.
The trained heating engineer removes the magnet at least once a year when servicing the boiler. Sludge that is trapped is flushed out, benefiting the filter and the system’s functioning.
Yes. Without a magnet filter, sludge can ruin pumps, valves, and radiators. By including a filter, you prevent breakdowns, saving you money, and maintain your heater efficiently.
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