In message , Tom B
writes
I have been searching for a replacement electronic CH programmer that
does not depend on a battery for backup of the settings, planning
ahead for the time when I shall not be here.

I thought I had found what I need in the Drayton Invensys LP522
programmer. Their Product brochure states:

However, the Technical Details state that it has a lithium battery.
This probably has a life expectancy of 10 - 15 years maximum, so there
will come a time when it needs to be replaced, and whilst this can be
done ( http://west-penwith.org.uk/blog/archives/222 ) it looks a
tricky job for a non technical person.

Having done dozens, I'd say that breaking tangs etc are the biggest
danger, but hardly difficult - you need to be able to use a soldering
iron


Solid state non-volatile memory chips used in lots of domestic
appliances are cheap enough so I would hope that is how the settings
are stored, and it may be that the battery is there solely to maintain
the clock during power failure.

sorry, but no




--
geoff