if i branch in close to existing rad valves with 10mm pipe the same as the existing pipework to add extra rads will this cause a problem . Tracing the feed back to larger diameter would cause a lot of work
depends what size of rads and how many,when i fitted a rad in an attic conversion i tee'd off the rad pipes in bedroom below,pipes must have been at least 10 metres and attic rad worked fine.i used 10 mm speedfit pipe and fittings.
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