"John W" wrote in message
...

alex_sh@w wrote in message
...
All of the central heating controllers I have seen are programmable
over 7 days but I could do with one with a 28 day programmer to suit
my shift pattern. Any ideas please?

If your shift pattern consists of 7 day chunks repeating over 28 days (as
opposed to 3 days here, 5 days there etc) then you could consider the
quite
costly option of having two timers that you swap at the weekend one
programmed for one type of 7 days and one for another. As long as you
choose
a type thats easy to unplug from the backplate (which I think is most of
them) then the you should have no problem.


That *sounds* ok - except most of them run on batteries which are kept
charged by being connected to the mains via the backplate. The battery will
maintain the memory contents for a limited period when removed from the
mains. This period may not be long enough!

[Having said that, I've just looked at the spec of my Danfoss Set5
programmer - and that claims to hold the time of day and programmed on/off
times for 16 days when disconnected from the mains - so you may be ok].

Roger