I have adjusted the water flow on our Main Medway for the past 20 years. (I also use the is winter/summer control on the front but that is not sufficient for the change in the temperature of the incoming water.) But this year I cannot shift the water throttle. So I seek help, please, with two questions:
(a) how can I best free it up if it is seized? (And please note that I do *not* fancy using my impact driver on the brass/copper fitting which is "suspended" .)
(b) what is the best tool and where can I get it? I have used a 12mm flat screwdriver in the past. But that is not really big enough. (There are no decent plumber's merchants near me and I cannot find anything on line which is wide enough - I think the screw is 16mm - without being too thick. But it may of course be me who's too thick.)