Changed an AAV once. But apart from that I've never worked with it or sorted probs with it.
So not sure what needs to be done here.
Lady is deaf and communication is difficult so quesitons were kept to a minimum.
Bath doesn't drain and when basin used it bubbles up into bath. Same with kitchen sink. Worked previously.
The picture shows what's on otherside of bathroom wall where bath, basin and kitchen sink wastes terminate.
When cap is unscrewed everything drains fine.
What's the fix?
Cheers.

So not sure what needs to be done here.
Lady is deaf and communication is difficult so quesitons were kept to a minimum.
Bath doesn't drain and when basin used it bubbles up into bath. Same with kitchen sink. Worked previously.
The picture shows what's on otherside of bathroom wall where bath, basin and kitchen sink wastes terminate.
When cap is unscrewed everything drains fine.
What's the fix?
Cheers.
