Installing Rads whats the best solution?

Hi

I am installing 5 new Rads in an extension using 22mm Polyplumb above the floor insulation which will then have a screed over the top, I was going to use a 22-15 reducing elbow that speedfit now do, to convert from the 22 to 15 for the rad feeds (up pipes), but i cant get hold of these, the alternative is to use a 22 elbow with a 15 reducer, or to use an unequal tee with a stop end.

Any opinions what is best, as these joints will be under a new wood floor and in a bit concerned as to using extra joints?

Thanks

why are you doing it all in 22 you can use22x15x15 tees to reduce when necessary

The main reason for running 22mm is to improve on the heat, the old half of the house is all 15mm which on long runs and with several 90deg bends, i think stops it being very efficient.
So using 22 for allmost all the pipework should make sure the new system is better....

Was thinking maybe a few inches from the walls to use a 22-15 reducer and make up the connection with a couple of inches of 15 then an EF elbow and 15 up stand...

Captain5691 said:

The main reason for running 22mm is to improve on the heat, the old half of the house is all 15mm which on long runs and with several 90deg bends, i think stops it being very efficient.
So using 22 for allmost all the pipework should make sure the new system is better....

Click to expand...

You'll have to balance the system so the flow in the new pipes will be restricted down to match that in the old 15mm pipes. Otherwise it wouldn't be balanced.

The 22mm isn't necessary except where you need it to feed several radiators. 15mm can carry around 4kW and 22mm can carry around 11kW.