""when CH demanded first valve has to move to CH ( and or HW + CH ) position, and this then mechanically triggers a micro switch to tell boiler to refer to room stat and decide to turn on boiler!! ?
Read more: //www.diynot.com/forums/viewtopic.php?p=2905485#2905485#ixzz2hX4xefGr""
just realised this is not strictly true - bit more complex - as boiler will be on / could be on just for HW, then demand comes for CH,
um - does system check room stat first? yes it should do as no point to move valve is rooms warm enough -
so once stat give go ahead it tells valve to move and you have CH or valve triggers micro switch and then boiler is fired up and pump starts.
whew
I might have a good understanding of how my CH system works by time I have fixed it!! lol
Read more: //www.diynot.com/forums/viewtopic.php?p=2905485#2905485#ixzz2hX4xefGr""
just realised this is not strictly true - bit more complex - as boiler will be on / could be on just for HW, then demand comes for CH,
um - does system check room stat first? yes it should do as no point to move valve is rooms warm enough -
so once stat give go ahead it tells valve to move and you have CH or valve triggers micro switch and then boiler is fired up and pump starts.
whew
I might have a good understanding of how my CH system works by time I have fixed it!! lol