All, I have one of these water tanks (unvented) http://www.gledhill-spares.net/documents/accolade_(including_accolade_plus).pdf The anti vacuum valve is leaking (from the top) and I need a replacement, however it appears that the only places that stock it are not open on weekends. So my question, can I use something else temporarily?
defo not!!! these appliances should only be worked on by registered people, they work at pressure and could be very dangerous.