Well, prepare for a "The plumber cometh" thread. When I had the boiler fitted, the kitchen tap started dripping - only it's not in the kitchen, it's in a corner of the living room. So I changed both tap washers - it's a mixer tap. All was fine until now - the hot water tap is just spinning

I can turn the screw with a screwdriver, so at least I can turn the tap off/on. Will have to call the letting agent