Attic water tank slightly overflowing occasionally.

chabsey

I've noticed our attic water tank appears to be overflowing (water coming out the overflow pipe) - this seems to happen just in the morning or after a bath. I imagine it's related to the water usage of showers in the morning and that when the tank is refilling the ballcock isn't stopping the flow quickly enough. The only thing that gives me pause though is that if the ballcock was the issue then surely the tank should be overflowing more regularly if not constantly during the day?

Anyone ever encountered anything like this?

magicbastarder

weirdly, i spotted a slow drip from our overflow recently - and that two other houses i can see from our back garden also have drips.

chabsey

https://www.boards.ie/discussion/comment/120553270#Comment_120553270

Could it be peer pressure among over flow pipes?

NattyO

https://www.boards.ie/discussion/comment/120553270#Comment_120553270

Is there an issue with water pressure in your area? The area I live in has intermittent pressure issues, where the water pressure can get very high at times. When this happens, the kitchen taps in most houses drip, and some people get their attic tanks overflowing.

magicbastarder

yeah, we get variable pressure in the kitchen anyway.

NattyO

https://www.boards.ie/discussion/2058295131/attic-water-tank-slightly-overflowing-occasionally

If it's happening after heavy use, it could be that the ballcock is catching on something that only gets it once it falls a certain amount. This can sometimes be caused by the split pin holding the ballcock arm.

Water John

Usually the ballcock sticking a bit. This will mainly happen with a big draw, like for a bath or multiple flushing of a loo.

chabsey

https://www.boards.ie/discussion/comment/120553355#Comment_120553355

Thanks all - this does seem like it's the issue. I'll have a look and see if it's the split pin or something else causing it to catch.

Bargain_Hound

Had the same issue on a 20 year old ballcock. Was just sticking ever so slightly at cut off point, enough to allow water to keep filling the tank beyond the point it should. Easy enough fix.

chabsey

https://www.boards.ie/discussion/comment/120553372#Comment_120553372

Did you just replace the ballcock? Ours is of a similar vintage.

Bargain_Hound

https://www.boards.ie/discussion/comment/120553383#Comment_120553383

Yes, replaced. There was a stop valve feeding the supply so easy enough to do.