"For Q2 M8" wrote in message
om...
Thanks for the replies.
After a bit of an experiment it seems I may have got this wrong

I thought that I could control the hot water independantly, but it
seems that I can switch it ON indepedantly, but if I switch the
central heating on then the hot water is on anyway...

It just seemed a bit of a waste leaving the hot water "reheating" all
day... and the water gets VERY hot... after climbing around in the
airing cupboard and ripping up a floorboard it seems my system is
setup a little differently than I thought... I thought I had one of
these Y designs that had a valve somewhere between the boiler and the
hot water tank, but the only thing I can find is the pump (above the
boiler).. no valves anywhere (unless it is under the floorboards in
the hall).

Anyway, the hot water is very hot and I found the temperature setting
on the hot water tank, it's set to 70 deg C so I might lower that to
60 deg C.

Doesn't seem worthwhile ripping out the pipes and connecting a valve
and a new programmable timer.
Seems I have 3 options
1. live with it and see how much the gas bill is after winter.
2. get a combi boiler installed (can't really afford this at the
moment)
3. get a programmable stat (thanks for the suggestion, didn't know
about them)

One possible solution to your requirement is to replace the room stat
with a
programmable stat. You can than set your existing timer to switch the
hot
water on and off at the times you wish - and switch the heating to
continuous (manual). The heating will then actually be controlled by the
programmable stat - which enables you to have different temperatures at
different times should you so wish, as well as being OFF when required.

Would this mean that the hot water would be on whenever the
programmable stat called for heat ???

Any ideas which stat I could use, the current one is an old brown
honeywell thing with no model number on (or in) it. I could take a
photo of it and the small wiring diagram that is on the inside of it,
and upload it on the web somewhere ??

Cheers.

P.S please excuse any typos, in a bit of a rush !

I'm still not quite sure whether your system is gravity or fully pumped. It
was beginning to sound like gravity - in which case you *can't* have heating
without hot water - except that you mentioned being able to set the hot
water temperature.

What sort of control is it which enables you to do this? Is is a thermostat
strapped to the side of the tank, with wires going to it? If so, it must be
controlling something - such as a 3-port valve or zone valve. Where do the
wires go?

Alternatively, you could have a Cyltrol valve or similar in the return water
flow. This is purely mechanical, and works like the thermostat inside a car
engine - with an expanding bellows which cuts off the gravity flow when a
certain temperature is reached.

[Just a long shot - I presume you're not referring to a thermostat
incorporated into an immersion heater which, of course, would only have any
effect when heating the water electrically rather than with the boiler?]

If you can clarify this, we can determine what is or is not possible.

Roger