which is it likely to be?

[johnscales]

The last few times i've spent the weekend out i've returned to find an overflow pipe at the front of house which looks to have been dripping for a while.
I'm guessing after some deduction the reason is because i'm away and therefore not using any hot or cold water in the house but my question is :which is it likely to be, a ball cock malfunction of the cold water storage tank in the loft, or something to do with the boiler (don't know if the boiler uses overflow pipes for anything hence the indecision).
Once I return home and start using things as normal the drips stop.

 

[Fluffster]

Odds on it is the ball valve letting by a few drips which as you say will overflow when the tank is not being drwn from.

Pete

 

[Morris40]

It depends on were the pipe goes, It is most likely to be the ball valve in the cold water storage tank, as you are away and not drawing water the tank over fills and leaks, whilst home you draw more water off than can be replaced so no overflow, this is a common enough fault and easy to fix, That is though if it is the cold water tank overflow.

 

[johnscales]

If I need to fix/replace the ball valve what parts do i need or can i buy a complete unit.

Thanks

 

[Morris40]

just buy a complete unit as very cheap and easy to replace as long as there is an isolation point just before ball valve, should be

 

[gas_man_gaz]

make sure ya got a fibre washer or some ptfe (for the mains connection) if ya going to replace the lot