"MJA" wrote

I have a mixed 1-pipe and 2-pipe central heating system. The 2-pipe
circuit feeds 2 radiators added by a previous owner. It has been
difficult to balance as the 1-pipe circuit hogs all the flow. I have
now added a balancing valve to the entire 1-pipe system which seems to
do the trick. I only had a 22mm compression service valve to hand,
and it is not the best type of valve to make delicate adjustments.

My question is, what sort of valve should I be using to balance a
domestic heating system? I have found double regulating valves in a
web search which look just right, but at over 100 pounds for a 22mm
compression valve they are far too expensive for domestic central
heating.

MJA

This might just be one of the rare occasions where a gate valve could be
useful.
I know for isolation they are the pits, as they tend to seize shut etc.
But in your case, once the right degree of throttling is set, you won't
touch the thing again.
Also they present less of an inherent flow restriction.
I'll wait for the gate-valve-detestors to come and shoot me down now

Phil