Ask The Trades - Print Page

Ask The Trades
https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Plumbing Questions >> 8mm supply to radiators https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1415282942 Message started by Zac on Nov 6^th, 2014, 2:09pm

Title: 8mm supply to radiators
Post by Zac on Nov 6^th, 2014, 2:09pm

I am putting two new rads in my house. The other rads are fed by 8mm microbore so I want to feed the new ones with the same so as to have an even supply throughout the system. My plan for each rad is to put a 22 to 15 reducing tee on both the CH flow and the CH return and then on each 15mm line from the tees put a 15 x 8 reducing coupler to the 8mm microbore. I'm only a DIYer so I just wanted to check with the pro's that this sounds ok.

So this will involve two tees off the flow and two off the return. Is there a more efficient way to do it. I have seen 2-port 8mm manifolds but I think they involve soldering, which I've never done, so that option's out I think.

I want to put 8mm TRVs on the rads but the only one I've seen has been the Danfoss RAS-C2 in the Screwfix catalogue, where it gives the diameter as 8-10. Does this mean that it will fit both sizes?

Thanks.

Title: Re: 8mm supply to radiators
Post by thescruff on Nov 6^th, 2014, 5:21pm

Hi Zac [smiley=wave.gif] and welcome to ATT.

Answered the question elsewhere but a couple of points.

You need to tell us what boiler it is and where you intend to tee off the 22mm. Get this wrong and you'll risk reverse circulation.

You only need to tee off the main pipes once then split the 15mm 2 ways

The valves in the link are 10mm and come with a 10 x 8mm reducer