Hi all,

Just planning for conservatory self-build for which I'm sure there
will be many questions over the following weeks!

After much googling of uk.d-i-y it seems that extending the CH
pipework into the conservatory and plumbing into a decent finned
double rad is the way to go. The conservatory rad needs to be
controlled separately from the rest of the houses' CH as I may need
heat in the conservatory during periods when the main house stat is
not demanding heat and the boiler is therefore inactive.

Boiler is an ariston microgenus II31 combi. Control is by a battery
powered 2 wire programmable stat. Zoning is beyond my current level
of knowledge but I'm trying to plug that particular gap right now!
I'm guessing that I need to introduce a 3-port mid position valve to
the flow end of the CH and connect to it (a) the original house stat
and (b) a new stat to be located in the conservatory. The resulting 4
peices of wire (and this is where it gets a bit beyond me) I'm
guessing need to be connected to the valve in a configuration such
that continuity across circuit (a) opens the valve to position a,
circuit (b) opens to position b and (a and b) opens a+b. I think I'm
correct in understanding that the valve will also act as a relay so
that a single connection from the valve to the boiler can be used to
tell the boiler that CH heat is being demanded.

I wonder if anyone could confirm (or not) that I'm barking up the
right tree here. The bit I need further information on is the wiring.
Does anyone have any good pointers to where I may learn about this?

Thanks

Mike