On 5 Apr 2004 02:57:28 -0700, in uk.d-i-y
(stevep) strung together this:

(Lurch) wrote in message ...
On Mon, 22 Mar 2004 19:58:14 GMT, in uk.d-i-y
(Lurch) strung together this:

On 22 Mar 2004 05:32:21 -0800, in uk.d-i-y
(stevep) strung together this:

I have a gravity fed HW and pumped CH system with a programable
thermostat. If I have the thermostat programmed to come on all day
inc. overnight then the boiler keeps tripping in to heat the water
despite heat not being required for the CH.
Can I fit a thermostat to the airing cupboard tank so that when the
room temp is OK the boiler will not light up or is there some other
easy solution?

There is nothing on the HW side of a gravity system that would bring
the boiler on, so it must be the room stat calling for heat.

Now I've re-read the OP a couple of times I've decided that the above
statement is utter nonsense. Sorry for having to make everyone read
it.
On a more sane note, if the original two channel programmer is still
wired in then the system could be altered so that a permanent feed is
supplied to the programmable room stat, which then switches the boiler
and pump on. And the HW channel of the programmer switches on the
boiler only. The heating channel on the existing two channel
programmer would be defunct.

Have been on holiday but thanks for this reply-it looks like this is
the answer but how do I do it? I have a programable thermostat
connected to a landis and gyr rwb2.9 mechanical programmer.

Easiest solution is to change the existing 2 channel programmer for a
single channel to power the HW only. You will need to move the current
CH switch wire to the permanent feed in order to send a permanent feed
to the room stat. (You could just use the one channel on the current
programmer instead of buying a single channel.) That should do the
trick.
--

SJW
A.C.S. Ltd.