In article ,
nog wrote:
While I would like to move towards a more sophisticated system, we have
an old - and very crude - heating system, piped through ½in steel tube.
This means that even TRVs aren't an easily available option, let alone
any form of zone control.

If it uses 1/2" pipe, it means it must be pumped, so is amenable to
control by a programmable thermostat regardless of zoning or TRVs, etc.
Indeed might well give even greater savings...

The previous owner was in the habit of turning
the heating on and off at the non-functioning Sangamo time clock but we
introduced the now-dying time switch (which had been in my possession as
a retired spare). I just need to keep the present system functioning
uintil we can afford to replace it with a more effective alternative.

Replacing the mechanical timeswitch and adding a programmable thermostat
won't be wasted if and when you have a new system fitted - they can be
used with the new.

--
*On the seventh day He brewed beer *

Dave Plowman London SW
To e-mail, change noise into sound.