Gurgling Sink, Toilet, Bath...

[DB11]

Hi all,

I've read up a few threads on this topic as we have the same problem currently.

However when I remove the AAV in the loft, the problem is solved. Could it be that the AAV is faulty or does the removal just mask another problem?

 

[DB11]

Anyone?!

 

[Burnerman]

The AAV just let's a gulp of air into the stench pipe when there's a flood of water going down there.....do you still get a gurgle with the shower and basin, or just when the loo is flushed?
John

 

[DB11]

Thanks for the reply John.

When we let water out of the bath, the toilet gurgles.
When we flush the loo, the bath and shower plug holes gurgle.
The shower drains away slowly. The sink not so much.
The downstairs toilet and sinks appear unaffected.

 

[Burnerman]

Obviously we can't see the layout of your drains, or how good the fall of them is but the shower in particular should drain quickly enough - it's a 40mm drain which is more than adequate.
What you don't want is the water traps being sucked dry as that would let the smells in.
If it was mine, and all was perfect with the AAV off, I'd try a new one - especially if this is a fairly recent problem.
John

 

[DB11]

Cheers.

I'll try that and hope for the best...as the manhole covers are buried underneath decking...in the previous owners' wisdom.

 

[Hugh Jaleak]

I think you may be wise to get access to those manhole covers, and double check. If problems cease when the AAV is removed then it often can point to a blockage. If the drains are full (due to a blockage), then adding additional water means air needs to be displaced. It cannot escape upwards as the AAV is preventing it escaping so takes the next easiest path, by bubbling back through the traps. When the WC is flushed, when the AAV is fitted, does the water fill the pan, and then subside again?

Downstairs possibly not affected due to being on a different drain run, which isn't blocked.

 

[DB11]

Hi Hugh

Thanks for your input. I've ordered a new AAV now but your explanation makes much more sense.

Yes the toilet pan fills and then subsides, likewise with the shower tray that fills and then drains all of a sudden.

 

[Hugh Jaleak]

You've confirmed my suspicions. Sorry, but my money's on a blockage.

 

[Burnerman]

Mine too, if the loo is behaving like that
Time to expose those inspection chambers, I'm afraid!
John