Smelly Sink

Leblanc_2

We have a one and half bowl sink.
The half bowl has its own U-bend and drains into the same downpipe as the main bowl with its U-bend.
Despite cleaning out the U-bend and pouring down concentrated bleach there is still a periodic niff, like rotten eggs.
Curiously we had the same problem in another property we recently moved from.
I thought that odours were trapped in the water trap of the U-bend? Why is this happening? It seems to be defying the laws of physics!
Any thoughts?

navig8r

The overflow pipe from the sink can be overlooked as a source of smells..put the plug in, fill the sink and let it escape out of it for a while to give it a good flushing then squirt in some bleach. We also give the traps and pipes an occasional good flushing by putting the plugs in ,filling the sinks to the top then whip out the plugs to get a good whoosh of water down them.

Dave

Dave

rygon

yeh make sure the overflow pipe is set up correctly (flowing in a downwards angle at all times) as water can get left in there to stagnate if not careful