My Landis and Gyr heating timer does not keep time any more causing me to switch on H/W and C/H manually, it feels like the spindal or clock mechanics are gone is this a simple replacement and if so how do i find the model number to replace, some where i read about it might be a battery replacement required ????

Steven, July 2010

I'm guessing it's the mechanical rwb programmer (old mechanical)
Something akin to the one on this link:

http://media.diynot.com/118000_117104_8874_40701032_thumb.jpg

No batteries are available for this as it doesn't use them.
Replacements are many and varied, it has an industry standard backplate so many others clip straight on (two screws underneath), and use the same wiring configuration.

I generally use a Drayton as a replacement, the link shows the programmer, I'm not suggesting using this merchant or any other, try searching.

http://www.heatingcontrolsonline.co.uk/acl-drayton-invensys-lifestyle-lp241-24hr-programmer-p-105.html

Carefree, July 2010