wrote in message
oups.com...
my ideal isar he35 has been fine for the last 6 weeks since fitting
until this week, i noticed the pressure had dropped to 0.75 bar from
the usual 1 bar (recomended when cold) i topped it back up to 1 bar and
it held this until the central heating had been on again, when it had
again dropped to 0.75 bar. This has continued all week it never drops
below 0.75 and works o.k. i can see no apparent leaks and the pressure
release valve has not discharged any water, the maximum pressure
reached when running is 2 bar. The only mention in the handbook of 0.75
bar is the pressure at which the expansion tank is pre pressurised at.
has anyone any ideas

thanks in advance


diaphragm in expansion vessel ?


RT