In message , Gav writes
can you tell me owt about zero govenors please geoff, that is our
current subject, controls, and if you can tell me owt then i will
look good at class tommorrow!

Zero governors ?
Not the faintest idea, I've never heard of them
(Well not by that name)

it's the multifunction valve used in new condensing combis that you
cant adjust the burner pressure on such as in worcester bosch and
vailant's newer boilers.

never mind, i winged it anyway. hard stuff this learning gas stuff!

Good

Gav- I repair pcbs and fans, I'm not a fitter, keep that in mind



--
geoff