On Tue, 27 Sep 2005 08:50:23 +0100, in uk.d-i-y "TheScullster"
wrote:

http://www.thesculls.freeuk.com/Radpipes.jpg

Referring to image (which shows upstairs piping and radiators only), the
problem is little heat to new bedroom rad 7 and almost nothing to towel rail
6.

[snip]

Looking at the pipe runs and radiator sizes involved upstairs, are 15mm
mains simply not up to the job?

Assuming no physical blockage the first step would be to check the
balancing http://www.diyfaq.org.uk/plumbing/rad-balance.html

You have to consider the whole system not just the upstairs.

Balancing WILL allow you to get heat to all radiators, but that may
involve turning the hot ones down to almost zero flow (and hence low
output). Then you will know which runs are causing the low flow and be
able to think about how to fix it. Once balanced, you can decide to
sacrifice the rads on the bad run and open up the others again to
restore heat to the rest of the house.

Phil
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