Microbore Central Heating Problems Extra Quality Jun 2026

Installing a magnetic filter (like a MagnaClean) on the return pipe near the boiler is arguably the best upgrade for a microbore system. It captures the black iron oxide sludge before it reaches the boiler or clogs the microbore pipes.

Microbore’s small bore makes it highly susceptible to air locks—pockets of trapped air that stop water flow. microbore central heating problems

For decades, microbore central heating was the "go-to" choice for heating installers in the UK. Renowned for its speed of installation and minimal disruption to décor, it utilizes narrow pipework (usually 6mm, 8mm, or 10mm in diameter) rather than the standard 15mm/22mm copper. Installing a magnetic filter (like a MagnaClean) on

Serious consideration should be given to replacing microbore entirely if: For decades, microbore central heating was the "go-to"

Microbore central heating systems, popular in the UK and parts of Europe during the 1970s–1990s, use small-diameter copper or plastic pipes (typically 6mm, 8mm, or 10mm) to feed individual radiators from larger 22mm or 28mm main flow and return pipes. While space-saving and quick to respond, microbore systems are notoriously prone to specific problems.