Shower room smelling badly these last few days

pieroabcd

This is a close up. The top is flat. I couldn't get to touch it comfortably, but it doesn't look like a moving part.

The connection pipe is actually horizontal.
There could be a second connection pipe hidden under a basement on the kitchen extension.

Right now I've also felt a fai t smell of bleach, that I poured yesterday morning and flushed at 8pm.

Kiran

Unfortunately you can't tell if an AAV is working by looking at the outside, there is a diaphragm inside that allows air to flow into the pipe but that closes as the water goes through the pipe preventing the foul air being released. It could be stuck and that's what is causing the traps to vacuum out the water and allow the foul air in. If that's the case you can replace the AAV or extend the vent pipe above the eaves and just have a traditional vent cowl on top of the pipe.

pulliptears

I had 3 years of issues with an AAV in my en suite.  I replaced it ad as soon as I'd thought the issue was solved the smell would return.  A smell that could get so bad it gave you a headache.  Mine was in a built in box and didn't feed to the outside, the plumber theorised the box was far too tight for the AAV to work effectively and eventually I admitted defeat with the whole thing and had the entire pipe extended and venting straight outside.

Best thing I ever did.  Never had a hint of a smell in there since.

Eldi_Dos

Could part of the problem be that the outlet pipe does not have much of a drop to it, if getting plumber to replace AAV ask if pipe drop can be increased.

pieroabcd

All neighbours in the same terrace (5 out of 6 houses) have confirmed that they feel the same dreadful smell in their bathrooms, someone even in the kitchen.

One of the neighbours told me that when I started to feel the smell someone did some work to the sewer of the house of the end of terrace  (the people that I've been unable to talk to).

At this point I think that it's correct to assume that the problem is in the sewer?

If so, whose responsibility (and cost) is to intervene?
Should I call the water company?

fluffymuffy

Can you lift the lid on an inspection chamber to see if it is running smoothly?. Ideally one where you can see the water flowing through if you run a tap. If it's full of sewage then you have a problem.

pieroabcd

I don't have an inspection chamber, but Thames water has just come to clean the lines. Hopefully it's resolved 

pieroabcd

After emptying the sewers three times the camera revealed that they were clean, but I was still feeling the usual dreadful smell at night 
I did a wash cycle at 90 degrees with some sodium percarbonate (like oxy) plus a rinse with a disinfectant like Dettol and now finally it doesn't smell anymore.

Probably the washing machines pipes and the relative drains were tainted?

pieroabcd

Question: can a p trap empty out if the connection between the washing machine drain and the hose pipe is too tight and doesn't let air in?
I still have to check if there's a p trap at all in that drain , but since he adjacent sink is getting locked almost every day and it gets unblocked when the washing machine is on ... There must be a link. 
An airlock maybe?

pieroabcd

It was much more shocking than that. 
https://forums.moneysavingexpert.com/discussion/6553120/smell-coming-from-behind-the-toilet#Comment_80985924