Engineers thoughts on service valves?

whats the point! they are there to make life easier and cause a misery instead. Every sodding one i touch lately is quickly sitting in the palm of my hand as i sob and shake curled up in the corner of the room. :-)

in your opinions, do any work?

in my opinion they may aswell have a stick of kitkat in its place, then i can snap the f*cka off and enjoy it with a nice cuppa as i wait for the system to drain