I have a baxi combi boiler with a heat exchanger but the flow switch is leaking.......just needs a new washer( i hope!!). I wanted to know how to isolate this flow switch so I can put a new washer in question is I don't know how to do this. There is a wheelhead valve just a bit further up the pipe, will this isolate the valve or will I have to drain the whole system down?
dIMM (name says it all!!)