Sewer gasses in bathroom

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Any idea why I would start smelling sewer gasses in one of my bathrooms with a toilet and shower? This bathroom is closest to where the inlet to the septic tank is. I did some research on possible causes, but I'm curious to know what you guys think.

Someone says the septic tank might be getting full and need to be pumped. It has been awhile since the septic tank has been pumped, but I live alone. I don't understand how the gasses could be entering the house if none of the traps are dry though. Thoughts?

Also, I've tried to pinpoint where the sewer gasses are coming from in the bathroom, and I can't figure it out.
 
The sink ,shower and toilet have a trap that holds water to stop the gas as mentioned , also there is a vent that goes to the roof to allow the gas to escape . Is the vent clogged?
 
Your bathroom sink could be vented by a auto vent. Look under the sink and follow the plumbing up. If there is a small round piece higher then your pea trap. Then you have a auto vent. If so it could be stuck open letting the gasses in.
 
No auto vent under the sink. I forgot to mention I went on the roof and looked down the vent to see if I could see anything. I could only see about 3' down the vent, but didn't see anything.

New toilets were installed last year, I'm wondering if maybe the seal is broken in that bathroom maybe. Another thing I've always noticed which is weird, when I flush the toilet in that bathroom, I can hear the trap water for the sink next to the toilet gurgle. Not sure if that's normal or not..

*The vent is almost above that bathroom, but the window has been closed and doesn't really get opened ever.
 
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also there is a vent that goes to the roof to allow the gas to escape .


The vent sucks air in, after, say a flush, the air sucks in the vent pipe, so the vacuum does not suck the water out of the pipe traps.
 
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So do you guys think emptying the septic tank won't do anything, and is not the source of the problem?
 
The most likely culprit is the wax ring on the toilet. They are cheap and simple to replace-if you can't determine the source of the order that's the first thing I'd try. If that doesn't work and you really can't determine the source, then contact a professional.
 
Originally Posted By: sxg6
Another thing I've always noticed which is weird, when I flush the toilet in that bathroom, I can hear the trap water for the sink next to the toilet gurgle. Not sure if that's normal or not..


This seems like the symptom to troubleshoot first. The sink trap water should not gurgle when flushing the toilet. See if any of these links helps you out: https://www.google.com/search?q=flush+toilet+sink+trap+gurgles&ie=utf-8&oe=utf-8
 
Originally Posted By: sxg6
Another thing I've always noticed which is weird, when I flush the toilet in that bathroom, I can hear the trap water for the sink next to the toilet gurgle. Not sure if that's normal or not


That's not normal. The water from the toilet flush is causing a vacuum behind it, drawing air through the sink trap causing the gurgling sound. The vent is there to equalize the pressure, the trap gurgling means the vent is clogged or improperly installed.
 
Originally Posted By: Pop_Rivit
The most likely culprit is the wax ring on the toilet.


That would mean I'm as smart as you Pop_Rivit !
grin2.gif
 
Thank you for the link and the replies.

I did some reading in that link, and they said exactly what Fsharp said. So I went into the bathroom, plugged the drain with the stopper, and filled the sink with some water. Flushed the toilet, no gurgling sound from the trap. That makes sense that the toilet flush is creating a vacuum and pulling air through the sink drain.

I should also mention that the house is from the 1920's or 1930's, so some of the plumbing is a little older. We have replaced some plumbing in the house, but I don't think the vent has ever been touched (if it ever even had to be). The kitchen sink isn't vented at all even actually.

I'm not sure what the plumbing is like behind the walls, but here's what it looks like in the basement under that bathroom. So I'm not sure if the bathroom sink/toilet is vented properly, or clogged, but it's something for me to try and look into.

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One more odd observation that I'm going to look into more. I notice that after I shower, often times the water level in the toilet goes down in that bathroom.
 
Originally Posted By: Pop_Rivit
The most likely culprit is the wax ring on the toilet. They are cheap and simple to replace-if you can't determine the source of the order that's the first thing I'd try.


This.

We just did a remodel and one of the workers didn't properly seal my toilet after laying G the new floor. I had to purchase two pvc rings and a new wax ring to solve the problem.

I also heard gurgling whenever someone flushed the other toilet.

Two rings and a wax ring later my problem has been solved.
 
Originally Posted By: sxg6
One more odd observation that I'm going to look into more. I notice that after I shower, often times the water level in the toilet goes down in that bathroom.


The water draining from your shower is doing the same thing as flushing the toilet, creating low pressure that sucks a bit of water out of the bowl.

I took a look at that picture, and that vent is in the wrong spot to do anything for the bathroom. The vent needs to come off the drain around where the shower and sink are, upstream from the toilet. You may be able to tie into the old vent, or look into installing a studor air admittance valve.
 
Your picture looks like there is no proper vent for the toilet. Maybe not for any of it. I would say that is a bad situation and you need a plumber. Your library might have a plumbing book to learn about types of venting and drain requirements etc, like the Rex Cauldwell book or others.
 
the problem is likely with the vents - as evidenced by the gurgling - not likely anything in your photo. although I do have a question ... the part of the stack that you have labelled as vent appears to be something that was removed. do you know any history? you probably need to check your attic to start tracing vent lines.
 
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