Brand new noisy boiler

[Mike13]

If I even set more than one of the new radiators to less than Max it gets noisy again.

 

[Mottie]

well they were working before the new boiler was fitted, no radiator noises ever. I would presume that the plumber would keep the out and return the same as before, but I guess I shoulfd ask that specific question/

See what pipe on what side of the rad gets hot first from cold. Should be the TRV. side. Some TRV’s can go either way round though but the one I fitted years ago couldn’t.

 

[ianmcd]

it is very common that when a new boiler is installed that the flow and return get swapped, if that is the case it could be your TRVs that are causing the noise

 

[Mike13]

Plumber finally swapped around the pipes, noise has now gone, I am able to balance things now.

 

[ianmcd]

a lot more common than you would think @Mike13

 

[fixitflav]

Plumber finally swapped around the pipes, noise has now gone, I am able to balance things now.

Which pipes, the boiler flow and return? If they were the wrong way round it's not surprising strange things happened.

 

[Madrab]

If you don't have any zones or hw cylinder then albeit not ideal, you can usually get away with swapping the flow and return without any issues on a combi, especially if the main flow and return are centralised and the rads are reasonably equidistant from them.

It's when the TRV's are the older directional type when the problems start when as the valves will then start to bang when the flow's reversed, as seems to be in this case.