In an earlier contribution to this discussion,
mike wrote:

"Roger Mills" wrote in
:

Given a free choice (which I don't have because I inherited a Y-Plan
system!) I'd go for S-Plan every time. Yes I could (and still may!)
convert it.

Go for it - I did mine a couple of years ago, never regretted it, if
only for the reason I know what's going on.

All you need is enough room - my airing cupboard was tight!, and it's
easy

I posted some pictures of what I proposed a while ago, but i don't think
anyone commented - so I'll have another go.

This is what it looks like at present.
http://www.mills37.plus.com/cylinder.JPG

I propose to replace the 3-port valve with 2 x 2-port valves, but I need to
take the pipes up higher and back down again in order to get them in - but
there will be a vent pipe connected to the highest point. I also propose to
install an atomatic by-pass valve and to tee its output into the cylinder
return. [The HW and CH returns join under the floor, somewhere.] After
modification, it would look something like:
http://www.mills37.plus.com/cylinder2.JPG

Can anyone see any problems with this arrangement?
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!