On Thu, 25 Nov 2004 09:16:48 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Phil Addison wrote:
???

The "???" was because I'm not sure what you mean by "key down the output
valves and retain these settings."

Some think that when you fit TRVs, there's no need to balance a system, so
have the lockshield valve fully open. There's some truth in this in that
all rads will probably get hot eventually, but it might be that the last
in the chain does so very much later than the rest.

I would not credit it with having *any* truth. Its just a bodged system
which the TRVs *partially* (only partially) correct for. They might also
suffer a reduced life because some of them will have to throttle the
full pump pressure instead of the reduced pressure in a pressure
equalised (balanced) system.

So my comment meant that if you use the LSV which is set correctly on a
balanced system as the one you keep when fitting TRVs, you'll save some
work.

OK, got you. You could also swap the "already balanced" LSV to the other
end if you want to put the TRV where the LSV is, or just count its turns
and set the other end to that valve.

Phil
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