after reading couple of forums, changed the diaphragm (lots of holes) in boiler. feel confident changed ok??? microswitches 2,3 still not clicking, no power in actuating switch. I can activate hot water by manually pressing switch 1 and 2. pressure ok heating ok. Any advice. wanna move house don't want expense of new boiler and regs

Paul william, September 2006

its rubbish brand, you may try any other boiler

kayyens, April 2012

Check plunger under microswitch is moving forward when tap is opened, if not. diaphragm. if yes microswitch. 1.2.3 need to switch for hot water.no1 for heating. If not clicking manualy.microswitch fault

alan, January 2007

I'm looking for a Saunier Duval SD623 's service manual. Have you got in .pdf format ?
Thanks a lot for your time
Regrds
Gianfranco

Gianfranco, December 2006

swap micro switches around poss problem with micro switch no 3.check h/water and c/ heating thermistats.are micro switches in right position

paul, September 2006