Float valve not happy with taps

[DIY-JC]

Hello all.
When I use any of my cold water taps in the house, the part1 float valve in my cistern dribbles a little more water then stops, its as if when a tap comes on, the water in the pipe to the cistern drops back then pushes again forcing a little more water out. It stops doing it eventually, until the loo is flushed then the process starts again. I'm a little worried that this will reduce the life of the valve. Would a check valve before the float valve stop this by not allowing the water to run backwards down the pipe?

 

[blup]

I assume you are describing the effect the direct mains fed taps and wc have on the cistern. Pressure changes cause this and it shouldn’t affect the design life of the valve.

 

[DIY-JC]

Looking closer, the ball is just touching the side wall of the cistern creating a little bit of resistance, so my guess is the change is pressure is pushing the arm to the fully closed position.
It's an old Burlington bell style cistern and the arm looks like a map of spaghetti junction to get it around the bell so I dare not bend it any more.
I'll live with it.

 

[DIY-JC]

Sorry blup, to answer your assumption - spot on!

 

[Nige F]

Looking closer, the ball is just touching the side wall of the cistern creating a little bit of resistance, so my guess is the change is pressure is pushing the arm to the fully closed position.
It's an old Burlington bell style cistern and the arm looks like a map of spaghetti junction to get it around the bell so I dare not bend it any more.
I'll live with it.

maybe get a tubular float rather than a round one ? Or a soldered copper one and ding it one side