Magnetic Filter London

Protect your boiler from magnetite sludge with a magnetic filter — essential in London's older iron pipework. Installation from £150, annual clean from £65. All 33 boroughs, no call-out fee.

🔒 Boiler Warranty Requirement

Worcester Bosch, Vaillant, Viessmann, Ideal, Baxi, and most other major boiler manufacturers now require a magnetic system filter to be fitted as a condition of the full manufacturer warranty. Without a filter, heat exchanger damage caused by magnetite sludge may not be covered. We fit a filter on every boiler installation as standard.

What does a magnetic filter do for a boiler in London?

It fits on the central heating return pipe and uses a powerful magnet to trap magnetite (black iron oxide sludge) before it reaches the boiler's heat exchanger. London's iron pipework produces magnetite continuously — without a filter it accumulates on the heat exchanger, causing kettling, efficiency loss, and premature failure. Most major boiler warranties now require one.

Do I need a magnetic filter if I have a new boiler in London?

Yes — Worcester Bosch, Vaillant, Viessmann, Ideal and most others require a magnetic filter as a warranty condition. Without one, heat exchanger damage claims may be rejected. In London especially (Victorian iron pipework + hard water), a filter is essential, not optional. We fit one on all boiler installations.

How often should a magnetic filter be cleaned in London?

Annually — ideally with the boiler service. In the first year on a sludge-heavy London system, clean every 6 months as years of accumulated sludge is flushed through. We include filter cleaning free in every boiler service visit.

What is the best magnetic filter brand for a London boiler?

Adey MagnaClean Pro2 (most specified, warranty-accepted by all manufacturers) or Fernox TF1 (engineer favourite, dual magnetic + mesh filtration). Both work equally well in London's hard water conditions. Avoid cheap unbranded filters — weaker magnets miss fine sludge.

Where should a magnetic filter be fitted on a London boiler?

On the central heating return pipe, as close to the boiler as possible. Not on the flow pipe. Isolation valves must be fitted either side for annual cleaning without draining the system. Side-entry models (Adey Pro2, Fernox Compact) fit London boiler cupboards better than inline models.

How much does a magnetic filter cost to install in London?

£150–£220 installed (filter + isolation valves + fitting). With a new boiler: £60–£100 (part only, no extra labour). Annual clean: £65 standalone, free with our boiler service. Power flush + filter: £450–£650 — the complete protection package.