[codell01]

We have a fiberglass shower that is 12 years old. Without warning, we had a serious sewage gas type of smell emitting from the master shower drain. This shower is used daily, so the p trap is not dry and it is holding water. There are no drainage issues. We have tried Zep Draincare, bleach, vinegar, and other disinfectants. The odor only stops when using the shower, but returns in about 10 minutes after we turn the water off. Also, there was a 2 week period of time in which the odor completely disappeared when we were out of ideas and waiting on the 1st plumbing appointment, but the odor returned.

We have had 2 plumbers out, but they are unsure of the cause. One said it was the worst smelling residential shower drain he has smelled in his career. Both agree that the p trap is good. They snaked the drain thinking that maybe there was organic matter collecting in the plumbing. They placed a Sure Seal to help, but the odor still escapes into the bathroom. The 2nd plumber suggested that it is possible that water is getting under the pan and I should have the shower replaced. I would hate to have the shower replaced if that is not the problem. I do not see any cracks. I am currently conducting a shower pan test, but so far there has been no change in water level.

 

[Tom738]

We have a fiberglass shower that is 12 years old. Without warning, we had a serious sewage gas type of smell emitting from the master shower drain. This shower is used daily, so the p trap is not dry and it is holding water. There are no drainage issues. We have tried Zep Draincare, bleach, vinegar, and other disinfectants. The odor only stops when using the shower, but returns in about 10 minutes after we turn the water off. Also, there was a 2 week period of time in which the odor completely disappeared when we were out of ideas and waiting on the 1st plumbing appointment, but the odor returned.

We have had 2 plumbers out, but they are unsure of the cause. One said it was the worst smelling residential shower drain he has smelled in his career. Both agree that the p trap is good. They snaked the drain thinking that maybe there was organic matter collecting in the plumbing. They placed a Sure Seal to help, but the odor still escapes into the bathroom. The 2nd plumber suggested that it is possible that water is getting under the pan and I should have the shower replaced. I would hate to have the shower replaced if that is not the problem. I do not see any cracks. I am currently conducting a shower pan test, but so far there has been no change in water level.

Sewer smell means you're getting air to that location from the plumbing somehow. It could be a crack in a pipe past the trap, for example. Or another source in the bathroom that the water flow from the shower is somehow masking the smell of.

I would try checking the other traps and seals first (other bathroom fixtures), running water and checking for leaks there, maybe replacing the wax ring on the toilet. After that you might need to think about opening up the plumbing under the shower.

Disclaimer: non-plumber.

 

[ben's plumbing]

you may be getting trap seal pulling from another fixture ...have someone flush commodes one at a time ..then fill sinks.. drain one at a time...see if it pulls the trap seal and allows sewer gas in...maybe a clog in the vent..?????

 

[Chrisathome]

I would advise to do what bens plumbing has suggested, it sounds like the trap seal is being pulled due to a venting issue.

 

[codell01]

So I completed the shower pan test on 3/21/16. I added more Zep Draincare to this water prior to draining the water. There was no change in water level after leaving the water in the pan all day. After I drained it, the smell has yet to return. This was 12 days ago. Now, we had stopped using this shower for about 1 week prior to the shower drain test and used it for the 1st time today. So far, there is still no odor. In regards to a vent issue, the plumber said that we don't have a vent associated with this shower. The odor was definitely coming from this drain, with no odor emitting from the garden tub, 2 sinks, or toilet in this particular bathroom. There are no visible plumbing leaks from any other sources in the house. The smell does not return when we flush either toilet, any of the sinks etc. Both plumber said that it is not the wax ring on the toilet. They also both assure me that there is no way that it is sewer gas because of the p trap holding water, but it sure smells like sewer gas to me. The million dollar question here is why it will disappear and then return! If it is a crack somewhere, the smell would be constant right? If the trap seal is pulling, wouldn't it always do so? The 1st time the odor stopped for no reason, we had continued to use the shower. This time, we have not used the shower. What is the variable that is causing the odor to come and go every few weeks??

 

[woodchopper65]

from the strainer screen on the shower down to where the trap seal water is, about how much distance is this? how long is the pipe?

 

[readar]

As I've worked on some of my own home plumbing projects I've found that when you crack open the pipes sometimes you get a lot of sewer gas coming out and sometimes next to nothing, city sewer variables which I don't know anything about.

Also, internal house pressure may be one reason, ie. all windows closed and bathroom fans and dryer running creating negative pressure will draw the gas in easier.

 

[DragonKing]

Rest assured there is a clog somewhere in the line that the shower attaches to. It does NOT have to be at the shower drain. The clog - probably from the sink (hair) or the toilet (tampon/baby wipes) is big enough to interfere with the venting inside the pipe. The smell comes from the shower drain (lowest drain in the line) when the improper venting in the pipe results in the shower water displacing the air in the pipe.....water goes down, air comes up.

Snake the entire line, starting with the most probable (toilet), then the sink, then the tub, etc.

The blocked vent isn't coming from the roof, but rather the blockage is INSIDE the pipe itself. Find the clog, remove it, and your entire line will vent the way it is supposed to and your shower drain stink will vanish.

 

[jmon]

Welcome to the forum dragonking.

Good advice, but the thread is over 5 moths old. Sometimes posters don't post the final results and post can be misleading. I'm sure the OP found a solution by now.

 

[Javiles]

Old Post but if you want to rule in or out sewer gases? smoke test the system no guessing seeing is believing.