Flow and Return

[Dad'n'lad]

Hi. I will be demolishing an old extension next week, in which there are three rads.
I would like to cap the flow and return at house wall level, so that when i replace with new extension, i can create a copy of the missing system.
Can i just cap off the 22mm pipes, or is there a need to keep the flow going for the rest of the house rads?
Thanks

 

[terryplumb]

Just cap the flow and return legs to the extension ,preferably with isolation valves . That would enable air to be released,if necessary,and ease of draining later on.

 

[Dad'n'lad]

Cheers Terry.

 

[Madrab]

Do the 22mm pipes just head to the extension or do they head off either upstairs or into the downstairs?

 

[Dad'n'lad]

Just the extension Madrab. And when all is finished, I intend to take off the iso valves and solder the system as it was. I've read that it's a big risk to leave them on and just carry on from there.

 

[Madrab]

Yes, never leave ISO's on the system, they're not designed for the sustained temps and chemicals found in a central heating system. Short term should be fine though.