Hello and a question.

[mattanglo]

Hi everyone, I've just joined this forum after reading for a while, as I have a question that I hope I can get some advice on.

I am about to begin first fix on my single storey extension that I am building and would like some advice on the piping for central heating.

I have had a Worcester Greenstar 29/30 CDI boiler and 270L tank installed as an unvented system. This is connected to the existing single pipe system in a 1960s bungalow.
I now need to run the plumbing for the new radiators in the extension as well as 2 additional rads in the bungalow for a remodelled area, the intention being to get the extension habitable and then rewire and re plumb the existing bungalow to bring it up to spec.

I would like to do the plumbing for the extension myself using Hep2O as I have metal web joists overhead and open stud walls so access is good. I am not running any plumbing below deck as if anything goes wrong I would rather be replacing plasterboard than expensive flooring!
I have come up with 2 options and would be grateful for feedback and advice about them, I have attached plans.

Option 1 - 22mm feed and return pipes from the existing copper feed and returns off the boiler. The 22mm pipes T off to feed all the way to the rads with the drops from the ceiling in 15mm and then short copper tails through the plasterboard to the rads. My concern with this is have I created a system that will be hard to balance?

Option 2 - 22mm feed and returns from the existing copper to boiler running to 2 manifolds - manifold 1 feeding the new rads in the bungalow and manifold 2 feeding the rads in the extension. All pipes from the manifolds to the radiators will be in 15mm. This option seems to me to reduce the chance of imbalancing and also reduces joins apart from at the manifolds and rads.

I would really appreciate any feedback or advice on these as a little bit of knowledge is a dangerous thing!

Cheers

Matt

 

[ShaunCorbs]

Option 2 would be the best if you have the space

And depending on length of a few runs might need a few rads in 22mm

 

[mattanglo]

Hi Shaun

Thanks for that - so for the 2 rads at the right hand end which are about 8metres from the manifold (more like 10m with the drops) I should increase the pipe size to 22mm. Maybe the best way to do that would be to take the 22mm feed from the end of the manifold and run that as a single pair of feed return pipes and then split via a reducing Tee down to 2 sets of 15mm feeds and returns for the 2 rads.

I have rejigged my plan to show what I mean, I have also applied the same logic to the first manifold i.e. 22mm feeds into the manifold, 15mm branches off and then continue the 22mm feeds from the end of the manifold onto the 2nd manifold.

Cheers

Matt