Hi Beetle and welcome...Originally Posted by beetle link=1208690984/0#0 date=1208690983
Sorry to inform that its very unlikely an anti-vac valve. If they fail, you will see normal pressure indicated on start up which then drops to zero when you purge the steam wand. All is normal again until the machine is cold...
I fear that your machine may require a brain transplant- i.e a control module....The bit is $200+ plus labour if required. Alternately, the element has failed (slowly) and need to be replaced. If you check the element for resistance (machine switched off and unplugged), you will get ~45ohm...If not, its just a dead element.
I sincerely hope Im wrong on #1 ;)