On 28 Nov 2006 17:20:06 -0800, in uk.d-i-y "Velvet"
wrote:

Velvet wrote:
(and snipped)
Velvet

Right, another idea. The bathroom rad's definitely the first to heat
up, and the only one without a TRV. What about... shutting off all
other rads, and closing the bathroom one in steps, till just before the
boiler starts threatening to kettle. That'll leave me with the minimum
flow rate (there is nothing in the manual for the boiler about this at

Yes, that would be the way to set the LSV on a rad being used as the
by-pass, but I thought you said your combi has built in bypass?

all!) - and I can then balance the rest of them (albeit they will be
further away from the boiler than the bathroom rad and thus
theoretically should have the LSV's opened wider than the bathroom,
which appears to mean pretty much wide enough to fit an articulated
lorry through)?

Just balance the rest as per the FAQ. You might finish up with a
different temperature drop across the bypass rad than all the others,
but so long as you are warm enough its nothing to worry about.

Oh, and I've read BOTH balancing faq's. I think a good thing would be

I recommend this one http://www.diyfaq.org.uk/plumbing/rad-balance.html,
but then I would, wouldn't I?

to simply reduce the pump speed, but I can't find anything in the
manual about that being possible to do on this combi (it's a

Yes, if the temp drop you finish up with is less than the 11C typical
you can reduce the pump speed.

non-condensing 5-ish years old Saunier Duval SD30e, which is apparently
a Vaillant in disguise?) - it just says restrict the flow using a valve
across flow and return.

As I said in the reply to your other post, I don't follow that. Maybe
someone else with that manual can clarify it.

At least setting it all back how it was when I started it easy, I
suppose LSV's to fully open - no faffing about writing down number
of turns needed to close them before I started fiddling

Velvet

Phil
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