blocked CWSC overflow?

[Jennie]

Hi all,
I've heard it is quite common for over flow pipes on CWSCs to block.
Is this true?
In which case, how and why do they get blocked? And how would you test it (ie, hold the ball valve down and force the water to overflow)?
Do you routinely test the overflows when fitting a new FOV valve?
Thanks again for all your advice. Tis much appreciated.
Jennie

 

[village idiot]

you will soon be looking for an apprentice. when that time comes, remember me, k.

CWSC overflows rarely block. Yes, if a new valve is fitted, then it will be unwise not to test that the oveflow is working properly. last thing you want is a flood from CWSC in loft

 

[townfanjon]

jennie, as VI says they rarely block, but one thing that happens loads are suitcases, xmas trees, old toys ,etc etc etc are thrown on top of pushfit overflow pipes and they obviously come apart.
Cover your b*m (I would have said *rse if you were a bloke lol) and test the overflow because if something happens you will get blamed.

 

[jonnyswamp]

Take a short length of hose with you, insert into o/flow tank connecter and blow first to check its clear, then overfill and check for leaks along pipe run
A lot of the time the only indication of a duff filling valve is a damp patch on ceiling due to leaking o/flow pipe as some discharge into gutter out of sight