I have replaced the batteries in my Rev 24 heating controller and now the LCD is blank and the unit wont switch on

Chrissy, July 2016

Check the batteries are in the right wayround

Check the battery terminal is not fouling on any of the plastic mpunding (had that once with a specific battery powered device when I used "standard" batteries that turned out to have a positive terminal slightly wider than normal)

FWIW there is an online copy fo the manual here:

http://w3.siemens.co.uk/buildingtechnologies/uk/en/building-automation/residential-controls/documentation/Documents/REV24_Operating_Instructions_en.pdf

XXX, July 2016