overflow problems All aspects of plumbing questions and answers, help, tips and information

[carlyann]

Need some advice.. l live in an upper cottage flat. my downstairs neighbour has pointed out that the overflow is gushing at times. she first mentioned it had happened whilst we were on holiday for two weeks and no one using water etc. apparently we came home and it stopped. she has now said it flows early in the morning and sometimes afternoon aswell. my partner had checked the tank in the loft area and all looks as it should. not sure what the problem is. any help woud be great... if l see my neighbour approaching me again before l'm even out of the car from work,think l might throttle her.

Thanks

[alavapint]

It sounds as though the ball/float valve is leaking, and when you are away from home, it allows the tank to fill and then overflows.
When you get home and start using water, the water level drops and the leak will go unseen.
It may look OK, but is the water level in the tank almost up to the overflow outlet ?
If it is you may get away with bending the arm of the ball valve downwards ( providing it is brass ).
If it is plastic, it will need adjusting. Personaly I never try to replace the washers within the valve, I always relace the whole valve.