WC Ball Valve question (prob amateur question!)

[DrEvil]

The cistern on the toilet in our bathroom overflowed due to the ball valve dripping when it should have stopped the inflow of water (well that and the overflow was too high). That ball valve had been in around 15 years as far as I know so assumed it had bit the dust.

So I popped down screwfix and picked up a new one. Installed it no problems .... except it still drips. No where near as bad and not overflowing over the top of the cistern, but after 10 hours of not flushing it is still dripping say every 30 seconds.

Now this one did come with a high pressure valve and a low pressure valve and wondering if it is due to the wrong one being in place. I don't know the pressure but the water is coming via a cold water tank in the loft so it isn't the highest pressure. Does anyone know if it likely to be this or just a duff unit?

I know I can change over the valve and find out but it means draining down the cold water tank one extra time and so I thought I'd ask here first quickly.

Cheers for help in advance!

 

[Hugh Jaleak]

Having it set for high pressure on a tank fed system wont cause an overflow, just usually means cistern will take ages to fill. If its still overflowing then either the ball float is set too high allowing it to overfill or theres muck in the valve, preventing it from shutting off properly.

If it is tank fed have you made sure there is not foreign matter in the supply tank that is getting dragged into the pipework supplying the toilet?

 

[JohnD]

you might consider taking it off to check that you have installed it correctly, not cross-threaded or anything

also look and see where the drip is coming from in case there is a crack or poor joint in the pipe

to guard against grit in the valve, take it off and wash the parts, and turn the water on briefly with the valve removed so that water squirts out of the pipe and dislodges any grit.

 

[DrEvil]

Oh this is annoying.

Right, well I stumbled across another problem when I went to put the cistern lid on in that this new valve is a fraction too high, so thought I would take it off, put the old one back on, but with with the new valve which I could wash through.

So I did and I flushed through the system for a bit too.

But still seem to get this tiny drip that goes on for hours. I've set the water level low so it's not overflowing at the moment. Is it likely to be a dodgy valve then?

Looked around for shorter ball valve units but the other ones don't have such an extended arm and I'm concerened it will clash with the flushing unit!

This should be so difficult!