Does anyone here know about plumbing? I'm having a problem which is perplexing me. I'll try to explain it as best as I can.
My bathroom sink is giving off foul sewer gas but only for a few seconds when i run the water. I've come into the practice of stopping the sink with a rubber stopper before I turn on the faucet and then removing it after a couple seconds. I'm led to believe that when the water from the faucet shoots straight down the drain it creates a turbulence that allows gas to escape, and when I stop the sink and let it fill a little bit the slow draining of the water prevents this escape of gas. Another thing is when I flush the toilet and then look down the sink drain I can see the water in the trap moving around a bit. I know a partially blocked vent pipe can cause water to be siphoned out of the trap causing escape of gas, but wouldn't I be able to smell it continuously even when water isn't running in the sink?
![plumbing-basics-ga-1[1].jpg](https://i.imgur.com/buxtJxz.jpg "plumbing-basics-ga-1[1].jpg")
>>1020402
Sounds like your sink plumbing vent it is blocked. It happens. The P-trap in your drain is preventing the gas from getting into your bathroom (good) but the gas is unable to vent because the vent is plugged (bad). When you run the water gas sneaks in past the P-trap. Running a snake from the roof down the vent stack can clear it, but it can be tricky if its not a strait shot.
>>1020402
My gut told me to say check your vent as I was reading, and then I got to the part where you said you'd heard a vent can cause this. So have you checked the vent? Also, how many drains use this vent and what diameter is it? It's possible the plumber installed one that is too small.
>>1020402
check how big your p-trap is. You may not have enough inches of water column to act against the sewer gas pressure.
>>1020418
It's almost like a meme on here now, but tell your landlord. They probably won't do anything, but at least you tried, and if you're smart you'll do it by sending them a carbon copy, in case something bad happens. But in all reality, this is probably not nearly enough for something bad to happen, so good luck. Also, >>1020425 could be right too.
>>1020425
It is 1 1/2" thin wall plastic. The stuff with the compression fittings.
>>1020402
I have the same thing in my bathroom sink anon. One day I realized the bathroom sink was the only original fixture in the house, which was built in the 60s. So I determined it was actually a buildup of sulphur inside the pipes, so I intentionally clogged the p trap and soaked it in bleach for a day. After that I got a hot pressure washer from a buddy that cleans kitchen exhausts and blasted the drain out, no more smell.
>>1020442
Ps. I actually spotted yellowy buildup just below the mouth of the drain and wiped it out with a paper towel to analyze ( smell)
If you have an S trap instead of a P trap that could cause it because gas would get caught and released when you run water through it
