: Specific radiators (often downstairs) remain completely cold or only lukewarm while others are hot.
Occasionally, debris left behind during installation—such as copper shards from cutting pipes or excess solder—can become lodged in the narrow bends of the pipework. blocked microbore
To prevent recurrence, engineers often install a magnetic filter (like a MagnaClean) on the return pipe near the boiler. This filter catches sludge particles before they can circulate back into the microbore pipes. blocked microbore