Giovanni
: I have a toilet that starts to run on and off. The flush valve is a fluid master 400A. : The flapper is new & the seat of the Douglas valve is good. does anyone know why this is?For the toilet to run, water is either leaking from the tank. (try replacing with a high quality flapper) or the fill valve is not shutting off. Sometimes even new flappers will not seal right. Checking for cracks in the tank should be tried also.
