Water Flowing from sink when toilet Flushed??? Please HELP

[psk]

hi guys,

i got this problem with my customer's toilet, when they flush their toilet there is water coming out of their sink. It's the same problem with their neighbour who lives above him. Its an aparftment.

I suspect there is some kind of blockage in their stack system but what is your say on this fellas?

Do we need some kind of a Air Inlet Valve?

I havnt been to the job yet im just explaining as i have been told by my client.
He says i will have to access the pipes which are behind the plastere board as there is a leak there too.

Thanks

 

[Resolute]

When you say running from the sink, do you mean the trap is being syphoned? If so, it sounds like a lack of air getting into the system and therefore likely to be a blockage in the vent pipe.

 

[secret squirrel]

How long has it been happening? is this a recent development, happening a long time, progressively getting worse. How long have they both lived there? Have they had this problem before, what was the previous answer if it has happened before.

Best thing to do is pop along with an open mind and most of these problems are easily solved. Just ask a lot of questions....

Its probably a blockage if its only just happened

 

[WHPES]

Try rodding out the stack and back through the bottom bend via the bottom inspection chamber.

Has it has always been the case and not just a recent problem?

If water is being sucked out of the trap and down the waste pipe and the problem has always been there, replace the basin trap with an anti syphon trap. If water is being pushed into the basin, you need to look a bit more deeply as it is probably bad design.

 

[psk]

Thanks for the tips guys. I havnt received a call from him to ask me to check the problem out yet.
As soon as i come to know about the problem i will update you.
thanks

 

[gaspastemania]

If no blockage try an anti vac trap , if reading this right you got bit of syphonage going on easily remedied

 

[truemanufan]

Sounds a little puzzling ?

 

[psk]

Sudoku?