"Roger Mills" wrote in message
...
In an earlier contribution to this discussion,
ARWadsworth wrote:

"Roger Mills" wrote in message
...

I reckon that if you connect the programmer's HW-OFF to terminal (5)
in the junction box, that would have the desired effect. The valve
would be energised all the time but the boiler would only fire when
either the CH demand was unsatisfied, or the HW demand was
*satisfied*. The latter is unlikely, since the water is not being
heated - but I suppose it *could* cause a problem if you turned the
HW off when you already had a tank of hot water. It would work best
if HW were either permanently ON or permanently OFF at the
programmer.

One small problem. Terminal 5 in wiring centre is linked to term 2 of
the cylinder stat. A HW off with the stat not calling for heat will
fire the boiler.


Yes, I did acknowledge that in the para above yours, but I didn't see it
as too much of problem if you used the system in a certain way. But, on
reflection, it probably *would* cause problems for the uninitiated - which
is presumably why Honeywell don't do it like that.

I think we're veering towards violent agreement! It's good to be able to
float ideas and to have them politely scrutinised. I wish that more of the
threads in this NG were like this one!
--
Cheers,
Roger



Excluded from politeness are the threads that involve anything to do with
CFLs, laminate,
Combi boilers, decking, solar power, wind power, spot lights or plastic pipe
cutting techniques. Did I miss any out?


Adam