A few months ago I fitted one of these valves to the toilet cistern
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have noticed recently that there is a noise coming from the toilet as though water is running, yet there is no water coming out of the valve. I know this because I lowered the adjuster thereby reducing the water level in the tank. then I marked the syphon and watched it filling after flushing the loo for about 5 or 6 times. I also lifted the valve to see if that would stop the noise but it didn't.
I was begining to worry about the loo overflowing as there is no overflow fitted to the loo. It is one of those syphons that has a hole in it for this purpose.
Can anyone please explain why am hearing this noise.