hi greg
im having a nightmare trying to reply to your question!!
attempt number 3!!
yes it sounds like the static disc needs replacing there cheapish and are available from www.heating-parts.co.uk.
they should be replaced with annual service.
if you do decide to replace the whole boiler i would be interested in buying the parts for spares for my 430 which is currently burning out static discs far too quickly (maybe faulty air adjuster).
good luck with repairs.
chris
chris
October 2008