Microbore Manifold. Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[mrb16]

I moved my manifold on my heating by 3 meters to make way for a door. It was 22mm into a 28mm copper Manifold with 10mm brass connections back out to 22mm, I extended teh microbore.

The manifold was old with compression fittings so I bought new Hep20 plastic manifolds in 22mm to replace . so now I have 7 radiators (14 feeds) from the new manifolds in the same place as they were before (all on the flow) but my rads are not getting hot now? this was working before with the old manifold but not now and I cant see that ive done anything different? can they work off the flow only like a one pipe system?

ive tried turning all rads offf bar one and it still isnt pumping round just going back through the bioler flow and return.

advice much appreciated

thanks

[plumbbob]

I don't understand "It was 22mm into a 28mm copper Manifold with 10mm brass connections back out to 22mm" or what you mean by ".....all on the flow" so it is difficult to advise.

A one pipe system barely works with large bore pipes so definitely won't work at all with microbore. Each rad must have a connection to both flow and return.

[htg engineer]

'I moved my manifold on my heating by 3 meters to make way for a door. It was 22mm into a 28mm copper Manifold with 10mm brass connections back out to 22mm'

I can't see why the 10mm would be increased to 22mm you must be mistaken ?

Bascially the only way to tell is to trace the pipes, you need one pipe from each radiator connected to the flow manifold and one from each rad connected to the return manifold - if you haven't - it'll never work.

htg