there is a washer inside the diverter valve. Turn the water off, drain down
the heating, undo the top left nut ( as you look at it) Undo all the screws
keeping the top on ( a bit of a bitch) Remove the top, making note of the
way the washer and spring comes off and replace with new diverter valve
washer ( previously purchased )Then put it back together
"Gav" ""gavbriggs\"@[cut the spam]blueyonder.co.uk" wrote in message
k...


during a job on my placement, fault on ariston eurocombi, i think it was a
a23 or 24 mffi, no hot water but heating ok.

diverter valve? well the pin that contacts the micro switch was not moving
fast enough, if at all, to engage switch and thus boiler not firing and
water wasn't getting hot.

now this is where i was thinking instead of jumping in with a new diverter
straight away could we try to clean out the old one?
re install and it work. no, didn't work at all.

new diverter installed, still not going fast enough to engage micro.

then, just to prove a point to my self after following the small copper
pipes to the brass valve where the blow off is and using man's
instructions to idenify parts(cant remember what it's called)i opened the
boiler drain off valve a little. then suddenly the boiler kicked into life
and supplied hot water(the hot tap was on all the while in the bathroom)

could it have been air trapped in the small capilaries that active a large
diaphragm on the diverter, or is it just some coincidence?

how would you have diagnosed the problem, bearing in mind the
boiler/heating was fine.