slow drainage

[WillyWarbux]

Hi, I'm after some 2nd (qualified or non-qualified) opinions on my current plumbing issue.

I have a bathroom with a really slow draining bath, a normally draining sink and a slow draining toilet where the water after flushed goes very high in the bowl.

The bath when empty, gurgles after flushing the toilet. I presume that air is being somewhat pulled from these pipes.

The toilet has a large AAV and the bath has a small AAV. Both appear in good condition.

I have a 2nd bathroom which possibly has a slightly slow draining toilet. It's not all that noticeable, but I started looking closer at how high the bowl filled after the very obvious problems in the 1st bathroom. It has it's own AAV too.

I had a plumber out to assess. After an hour and a half his advice was to purchase new AAVs for the toilet and bath, even though they look in great condition. He had no idea why these 3 separate units would all start slowly draining at exactly the same time as each other.

Surely there must be a common issue?

When we took off each of the AAVs and ran water down the toilet and the bath, we got an increase in intake of air and both went back to draining normally. This solidified the solution to the plumber that it's the AAVs that are at fault.

Plumber said he'd be pretty amazed if this was a blockage issue. My question is - wouldn't a part-blockage which is located in a commonly used pipe cause a reduction in air intake from the AAVs resulting in a slower flow of water?

Thanks for any advice/ideas!

 

[CBW]

I’d say You have a blockage somewhere. When you find it, I suggest taking a photo of it and send to your plumber. Unless the aav has failed, then you have a blockage.

 

[HERTS P&D]

Blocked drain line/manhole.

Andy

 

[Hugh Jaleak]

Common issue is, the drain all 3 go into is blocked. AAV's do exactly what it says on the tin, they allow air into the system. If there is a blockage on the system, the pipework is essentially sealed, so flushing 6 litres of water means 6 litres of air has to be displaced, which needs to find the easiest route out, which in your case is the bath. Removing the AAV's allows the air in the pipework to be instantly displaced as the water flows in, hence the WC's flush normally.

Nothing wrong with your AAV's. Replace your 'Plumber'.

 

[WillyWarbux]

Can confirm after getting Dynorod out, that this was indeed a blockage in the pipes outside of my boundary. Good news is that I found the problem, bad news is that 12 hours after clearing the pipes, the blockage has returned. :-/

 

[HERTS P&D]

Can confirm after getting Dynorod out, that this was indeed a blockage in the pipes outside of my boundary. Good news is that I found the problem, bad news is that 12 hours after clearing the pipes, the blockage has returned. :-/

..........................Good old Dynorod!

Andy