air admittance valve

[citreonman]

Hi
I am having trouble with the valve, the toilet when flushed with the valve fitted fills the toilet upto the top, I replaced it with a new one butI am having the same problem. I removed the valve and it flushes ok. CAN ANYONE HYELP
Mick

 

[HERTS P&D]

Post this in the plumbing section.

Andy

 

[^woody^]

Has it ever worked, and have you done any work on the wastes or drains recently - or know if neighbours have?

It is possible that the new one is faulty too

 

[Nige F]

You gotta blocked drain underground - simples

 

[citreonman]

hi
what I dont understand is that if I remove the AAV it works properly so I dont see it could have a blockage.
The only work done was a new path done by the council directly outside the house could this be the problem? They shouldn't have touched the pipewoirk
Mick

 

[HERTS P&D]

Nige has got this dead right.
I was called out to one today with the same symptoms, it was a blocked manhole. Jetted it through, now no problems.


Andy

 

[Nige F]

hi
what I dont understand is that if I remove the AAV it works properly so I dont see it could have a blockage.
The only work done was a new path done by the council directly outside the house could this be the problem? They shouldn't have touched the pipewoirk
Mick

You don`t need to understand - just believe I don`t understand quantum physics but I believe Stephen Hawking does

 

[RedHerring2]

They shouldn't have touched the pipewoirk
Mick

Is that your Somerset accent?

I have some time on my hands so my guess at an explanation is:

The AAV only allows air in, not out. So when there's a blockage in the pipework, there's no room for the water to enter the pipework without displacing something first. It can't displace the air while the AAV is fitted. But when the AAV is not fitted the air is easily displaced allowing the water to enter the pipwork.

 

[Nige F]

Spot On

 

[^woody^]

The blockage, if one exists, must be pretty close the toilet and would be backing up after a few flushes

Also, if there are any other waste connections to the stack near to the toilet, then the traps would be sucked out of them instead, when the toilet was flushed

The OP will have see what else is on the run to confirm if there is a blockage or not

If the valve is in the loft, then it could be freezing shut in the current weather conditions

 

[citreonman]

Thanks for all your comments It looks as if I'll have to have a blockage found
Mick

 

[Nige F]

first place to look will be the last manhole near the footpath/ boundary - assuming your house drains individualy to main sewer - there, you will find a blocked interceptor trap - All the best, Psychic Nige

 

[citreonman]

thanks for that
Mick

 

[citreonman]

Hi
Thanks very much I have found the blockage
Mick

 

[Nige F]

But where Mick, where - I need to verify my abilities