Filters and system protection: what they do and why they're specified
A magnetic filter and chemical inhibitor treatment protect a new boiler's heat exchanger from debris circulating in an existing heating system, which is why they're commonly specified alongside a new appliance rather than treated as an optional extra. The new boiler is the most vulnerable, tightest-tolerance component in the system.
The engineering behind system protection
Older heating systems accumulate magnetite sludge and other debris over years of operation, and a new boiler's narrower waterways are more susceptible to this debris than the appliance it replaces. A magnetic filter captures ferrous particles in circulation and is cleaned periodically, while inhibitor chemical treatment protects against ongoing corrosion. Manufacturers often make warranty validity conditional on this kind of system protection being fitted.
System protection: engineer's shortlist
- Magnetic filters capture ferrous debris circulating in the system
- New boilers have narrower waterways more vulnerable to debris than older ones
- Inhibitor chemical treatment protects against ongoing internal corrosion
- Many manufacturers make warranty validity conditional on system protection
- Filters need periodic cleaning as part of routine servicing
Where we deal with this
Published business details
- Based at 24 Bristol Road, Radstock, BA3 3EE
- Telephone enquiries: 07516 118198
- Opening hours: Monday to Friday, 8:30am to 5:00pm
Talk to us about system protection
Our advice: System protection exists because a new boiler is more vulnerable to old system debris than the appliance it replaces — it protects the investment, not pads the quote.
Published opening hours are Monday to Friday, 8:30am to 5:00pm.
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Services that cover this
Questions we get asked
- Is a filter always necessary?
- It's commonly required for warranty validity on new installs, so it's worth confirming this with your specific manufacturer's terms.
- Does a filter need maintenance?
- Yes — periodic cleaning is normally part of an annual service to keep it working effectively.
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