Toilet stinks / bathroom stinks !!

[jimbo1]

Sorry I know this has been covered a lot of time but I can't seem to find an answer to this one.

The new bathroom was installed by a trained plumber and looks great. However there seems to be an issue with very offensive sewer gas smells getting into the bathroom, which is worse when sewer activity is greater (mornings & evenings etc).


We have had our plumber back and he has checked all his pipework to be sound. We have then experienced further issues. No work has taken place on below ground piping whilst installing the bathroom, and we have one soil internal stack which stayed in the same place. We had no issues before the new suite went in. The manhole is not blocked.


I have checked that all water traps in the bath, sink and toilet basin remain at the normal height, and there is no syphoning or bubbling or leaks from any of the pipework. All water flows freely and quickly away on flushing, emptying of sink and bath. Also one does not effect the other if emptied and flushed in combination. We have an outside vent which has been investigated and it is not blocked as I have thrown buckets of water down it and it flows through the manhole. I have also had the local water board out to check and verify no issues with the drains or any know local problems to the sewer system or local housing.

Our plumber has been back since, and re-plumbed the bathroom again!


The smell continues the same, from the toilet. I have never seen a gas bubble pop up from under the U bend, so I can't say sewer gas is making it into the bathroom by +ve pressure / that route.
The smell remains strongest near the water holes and under the rim. The smell can build to a really unpleasant level some days. I now suspect the casting of the toilet to be the issue but there are no leaks. It is a back to wall toilet and does not have a wax seal underneath as it is self contained.

Our outside vent is connected to the lowest channel on the manhole, and ours and the neighbours sewage travels into our manhole via 2 of the upper/higher positioned channels. When I lift the manhole cover I notice waste can be left on the higher capped ledges so the water level is raising enough to cover the lowest channel. I am assuming this means the venting can be blocked off for short periods of time. However when I run everything the water flows through fine. I am wondering if the airtight cover is causing the water to remain high for longer than needed and slowing the flow causing venting problems. I also noticed today that next door don't seem to have an external vent on the side of their house.

I am confused by this smell. Very sorry for the very long post but I feel I have exhausted the investigations and still remain stumped.

Anyone willing to chip in on this ? I would be very grateful.

 

[Scott_1979]

So the smell comes from the toilet? And there is always a water seal in the pan? Perhaps theirs toilet tissue or such like stuff and siphoning water from the trap making the smell? Have your plumber investigate that?

 

[JCplumb]

Is there an overflow pipe on your new loo? Was there one on your old loo?

 

[jimbo1]

Is there an overflow pipe on your new loo? Was there one on your old loo?

There was one yes, and there is not one anymore :smart:

You have highlighted to me a major change that did not even occur to me. Can you explain the significance of how this has made such a disgusting smell occur ?

Thanks in advance

James

 

[rpm]

James I don't have the answer but can I congratulate you on such a well crafted first post.

 

[jimbo1]

James I don't have the answer but can I congratulate you on such a well crafted first post.

Cheers for the compliment It took ages

 

[JCplumb]

Well my thinking was, maybe the old overflow tapped into the stack or exits next to a drain or hopper, did your plumber properly seal the pipe?

 

[jimbo1]

Yes the old overflow went though the wall, that is now concreted over and there is no pipe at all now.

The new cistern has an overflow that somehow exits water not via the pan but somehow behind the water trap of the loo, then on into the soil stack. It also takes the same pipe as the flush water so I am guessing it is a pipe inside a pipe. So does this mean there is a direct route to soil stack. I was expecting to see the overflow water go direct into the bowl to be honest not just hearing it fall into the waste pipe behind the water trap!

Any thoughts.

 

[jimbo1]

I am beginning to wonder if this is the problem from another thread on this forum:

It turns out the smell was coming from a gap between the foul side and the fresh water bathroom side of the back to wall wc pan.

During the manufacturing process a channel is made between the supply water side and foul side which is manually plugged up with clay before firing at 1100 degrees C. In the case of these 2 pans the plugging did not seal the 2 sides and conceqently foul air was getting into the pan and hence making the bathroom smell.

I did check all traps and changed the bath traps for 76 mm ones to conform to Part H

Thanks to all for their advise and sugestions. Checking that the customer had not number 2'ed in the bath (as suggested by NickH) did required a degree of sensitive questioning techniques on my side!!

Claygate the sanitary ware importers provided a good service. Within 48 hours they sent a technical rep to the property in Hampshire from their base in Kent who confirmed my diagnosis, stated that there was at present no UK requirement to pressure test WC pans, offered some resonable advise and brought 2 replacement pans with him.

Air leakage between foul and fresh sides of a pan is not something I've ever come across before but something that I will be testing for before installing future loos.

Thanks again
Brooksie the wiser

 

[JCplumb]

Yes the old overflow went though the wall, that is now concreted over and there is no pipe at all now.

The new cistern has an overflow that somehow exits water not via the pan but somehow behind the water trap of the loo, then on into the soil stack. It also takes the same pipe as the flush water so I am guessing it is a pipe inside a pipe. So does this mean there is a direct route to soil stack. I was expecting to see the overflow water go direct into the bowl to be honest not just hearing it fall into the waste pipe behind the water trap!

Any thoughts.

Don't really get what you mean here, if the overflow taps into the soil and is an open pipe in your cistern then it will let smells in, a picture would speak a thousand words here.