micro bore solution

6 Feb 2006
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United Kingdom
just had a two storey extention built.

I have three new rads i would like to add on.

the house has a convensional heating system (header tank etc.) linked to a potterton boiler and the rads run off micro bore (10mm).

rad No. 1 is just a replacement on a different wall, so think i can just tap of orignal pipe work?

Rad No.2 and 3 are in the extra rooms, so ill have to track back to the flow return source?

just a couple of questions i would like to put out... I am struggling to find the manifold, are there any methods of locating it? and rcommended connectors?

In the the cylinder cupboard the flow and return pipes are visable but dissapear under the floor. if i cannot find the manifold where would be the best place to tap into the pipe work and are there any rcommended connetors ? (i was going to do it in plastic)

is there a limit of how far to run the micro bore from the manifold?

hope this is understandable.

would really appreciate any help, cheers
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How yours is piped depends totally on the installer.

Whilst 8 mm microbore was usually fitted using a manifold, 10 mm was often done just using normal reducers from 22 mm and 15 mm.

There is a limit on the length of 10 mm to feed a rad depending on the power of the rad. As a very rough rule of thumb about 3 m to the rad for 1 kW.

It may be easier to just take a 15 mm from closer to the origin. That should feed about 4 kW up to a distance of about 5 m to the rads.

All of these are just suggestions because they all depend on the design and setup of your system and the pump pressure.

What is almost bound to give problems is to just tee off from an existing 10 mm feed to a rad.

Thank you very much for your help, much apprciated.

think im going to go for the 15mm option, i just need two 22,22,15 t's on each the flow and return.

it might be a stupid question but is there a rule where or where not to T into these pipes??

or as another thought could i tee into the 10mm pipe as long as it was close to the origin (do they do 10mm tees with a 15 branch)


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