I think I've got a leak!

[jsimpson]

Hi,

The level in my header tank is normal, but there is a constant drip from the ballcock. If I push the ball down and fill the header tank by an extra inch or so then the dripping stops, but the next day the levels back to normal and the ballcock is dripping again. I've checked all the radiators, but there are no signs of leaks anywhere. The only conclusion I can come to is that the leak must be in the pipework under ground (I have a solid floor).
I'd be grateful of any ideas on how to locate the leak or any other comments on how to solve my problem.

Many Thanks

John

 

[sterose]

Hi,

The level in my header tank is normal, but there is a constant drip from the ballcock. If I push the ball down and fill the header tank by an extra inch or so then the dripping stops, but the next day the levels back to normal and the ballcock is dripping again. I've checked all the radiators, but there are no signs of leaks anywhere. The only conclusion I can come to is that the leak must be in the pipework under ground (I have a solid floor).
I'd be grateful of any ideas on how to locate the leak or any other comments on how to solve my problem.

Many Thanks

John

You dont say whether you are actually having any problems.

If you definitely aren't, I would suggest you stop worrying.

The drip is likely to be just the ball cock not putting enough pressure on the valve. Basically, as the ball cock rises, it presses a washer against a valve. Obviously, as the water rises, it puts more pressure on the valve, and the water flow slows down. The more pressure, the less water. Eventually, it reaches a point at which the water is only dripping into the tank, BUT at this point, the ball cock will not rise any further, because it is only a tiny drip. And so it will drip and drip, almost forever. This is why when you push it down to add a bit more water, it allows the ball cock to rise up further, and stop the drip.

The reason the drip starts again, assuming you have no leaks, is probably because of simple evaporation out of the tank (and possibly other sources).... and once the water level drops, we are back to the original problem, of the water dripping, but not filling the tank enough to make the ball cock rise to cut the water off.

 

[oilman]

The reason the drip starts again, assuming you have no leaks, is probably because of simple evaporation out of the tank.......

An inch evaporation in a day? Hardly likely.

If the valve is constantly dripping, it might be time to change the washer. Try this first and see if the drip stops.

 

[ChrisR]

Is the heatnig header tank higher than the domestic CW cistern (bigger tank). If so you may have a perforated coil in you HW cylinder. Check the level in the big tank over a long period of non use - if it rises...