Author Topic: Dumbfounded by sewage smell (Read 41039 times)

SavingMon(k)ey

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Dumbfounded by sewage smell
« on: October 15, 2013, 04:13:36 PM »
Ok, illustrious mmm'ers. When the heat kicks in, we get a sewage smell in the whole house. I've tried looking for the origin, but I can't figure it out. Only thing I can think of is a dry drain somewhere (maybe in the utility room where the furnace is? but I can't tell for sure if it's coming from there.)

Ideas???

Myrmida

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Re: Dumbfounded by sewage smell
« Reply #1 on: October 15, 2013, 04:52:25 PM »
No ideas, but I'd like to know the answer because our bathroom gets this from time to time. We haven't figured out a pattern yet.

MKinVA

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Re: Dumbfounded by sewage smell
« Reply #2 on: October 15, 2013, 05:33:16 PM »
Do you have a floor drain in the basement for overflow of washer, etc? If so, pour boiling water down it. It may have standing water down there causing smell. Or your main drain may be clogged. I don't think you can fix this with boiling water. May need to get rotor rooter to clean. In older homes with clay or galvanized pipes, tree roots can grow thru causing a clog and backup fumes or worse, liquid backup.

bandito

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Re: Dumbfounded by sewage smell
« Reply #3 on: October 15, 2013, 05:47:42 PM »
Maybe a dead mouse or something in you duct work or air conditioner.

bandito

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Re: Dumbfounded by sewage smell
« Reply #4 on: October 15, 2013, 05:59:51 PM »
May need to get rotor rooter to clean.

I think that is an inexpensive method to try as I have done the same in the past but before you do that read the following article. It's a story about how a gas line was retro drilled through the sewer and the house ended up exploding when a rotor rooter was used to unclog it.

http://minnesota.publicradio.org/display/web/2010/03/11/gas-line-inspections

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #5 on: October 15, 2013, 06:16:01 PM »
May need to get rotor rooter to clean.

I think that is an inexpensive method to try as I have done the same in the past but before you do that read the following article. It's a story about how a gas line was retro drilled through the sewer and the house ended up exploding when a rotor rooter was used to unclog it.

http://minnesota.publicradio.org/display/web/2010/03/11/gas-line-inspections
Holy cow, that's scary.

Well, we poured some water down the basement floor drain. I also ran the shower down there for a while (though I didn't really get a smell directly from either of those drains, but that may have been because it sort of comes in wafts). Will see if this helps.

We had all the ducts cleaned and a roto rooter out just 6 weeks ago, so I don't think that is the problem (well, there could be a dead mouse somewhere, but it definitely smells like sewage, not death).

Thanks for all the advice.

Kevan

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Re: Dumbfounded by sewage smell
« Reply #6 on: October 15, 2013, 10:19:16 PM »
Smells are like ghosts: they come and go and disappear and reappear and defy all efforts at detection.

A drain backup creates symptoms easy to spot. Absent those symptoms, a drain clog is almost surely not the cause of an odor.

A loose toilet can allow sewer gas to drift into a house. So can a dry drain trap or a broken pipe in a wall. I've seen all these.

One radical method of detection involves plugging the main sewer, taping the roof vents shut, taping(or otherwise sealing) the drains in the house, and then pumping smoke down one roof vent (a smoke bomb in a shop vac can do it) and looking for smoke emerging in the house.

Left

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Re: Dumbfounded by sewage smell
« Reply #7 on: October 16, 2013, 02:05:43 AM »
have you checked the main house pipe into the sewers? I had one backed up before, and it smells like sewage...

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #8 on: October 16, 2013, 06:14:49 AM »
So we poured some what down the drain last in basement by furnace last night. It *seemed* better for a couple of hours, but than it came back. We poured some more, but this morning it stinks again. How much water are we talking about that needs to go down that drain if it's dry and that's really the problem?

Left

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Re: Dumbfounded by sewage smell
« Reply #9 on: October 16, 2013, 06:36:56 AM »
hm noticed you are in denver, could it have anything to do with the floods you guys just had? I mean stillwater in the sewer system and smell coming up to house because it is connected. Do your neighbors have problem?

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #10 on: October 16, 2013, 07:12:28 AM »
eyem, our area was not affected by the floods at all. (Thankfully!)

I'm still thinking it's a dry drain but... what would be causing the drain to go dry? Could it be a venting problem that is causing a pressure difference that's sucking out the water? Or could the furnace, when its blower kicks in, be causing a pressure difference in the house that ends up sucking gas out of the drain? I know almost nothing about plumbing. Total guess. Also don't know what that line in the basement looks like and how it would go dry. Is there a trap, too? How much water is needed to fill the trap?

Greg

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Re: Dumbfounded by sewage smell
« Reply #11 on: October 16, 2013, 08:51:51 AM »
Your furnace may need more intake/combustion air. What is your furnace's source for this? If you don't know, ask a furnace tech to come look at it. Usually the furnace will get it's combustion air from the under-house crawlspace, garage (if un-conditioned and vented) or in some cases the house itself, but only if it's an old leaky house. New houses require combustion air ducting or some other provision. Sometimes homeowners will block off this venting to try and save on heat loss and cause problems, including CO dangers.

If it's a high efficiency type with plastic intake and exhaust ducts, make sure they're not clogged.

You only need a few cups of water to "wet" a drain trap. But, if the house is old the trap could be rusted out and lose the water that is supposed to block sewer gas. Usually you can see the water standing below the drain grate.

bandito

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Re: Dumbfounded by sewage smell
« Reply #12 on: October 16, 2013, 09:41:03 AM »
Smells are like ghosts: they come and go and disappear and reappear and defy all efforts at detection.

Not that I believe is ghosts or anything but apparently during their presents the can leave a fowl odder.

shadowmoss

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Re: Dumbfounded by sewage smell
« Reply #13 on: October 16, 2013, 10:52:40 AM »
If you have a garbage disposal try urunning hot soapy water through it while it is running (not actually chopping anyting at the time). If a disposal isn't run often it can get a bad smell to it.
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Greg

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Re: Dumbfounded by sewage smell
« Reply #14 on: October 16, 2013, 11:29:22 AM »
Rereading your original post, I'm wondering if you might have a bad burner or exchanger in your furnace. They can corrode and perforate after a long time, and this can cause unburned gas odor in your heated air. Got a CO monitor in the area? That would be prudent.

Also, rodents like to make nests in ducts (and furnaces) and they seem to pee on everything, could this be the odor you're getting with the heat on?

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #15 on: October 16, 2013, 12:06:35 PM »
The smell definitely come from the heating vent, not toilet, not disposal, etc. The furnace was just inspected as we bought the house a couple of month ago. No corrosion was mentioned. Considering we were running the whole house fan for several weeks after we moved in and didn't notice any smells, I really do think it's a drain problem that just started. I also in recent days noticed a couple of critters (a centipede and then a daddy long legs) in the bath tub. How else would they crawl up other than if the drain was dry? My guess.

ScottEric

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Re: Dumbfounded by sewage smell
« Reply #16 on: October 16, 2013, 02:02:43 PM »
Ok, illustrious mmm'ers. When the heat kicks in, we get a sewage smell in the whole house. I've tried looking for the origin, but I can't figure it out. Only thing I can think of is a dry drain somewhere (maybe in the utility room where the furnace is? but I can't tell for sure if it's coming from there.)

Ideas???

Do you have Cast Iron Pipes or PVC? In our house we had old cast iron pipes and the top of the horizontal runs all cracked. They were probably around 80-100 years old by the time it got bad enough that they were replaced. In our house you could hear the traffic out on the street through the cracks in the pipes if you were close enough to them, even without smelling much sewer smell.


bandito

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Re: Dumbfounded by sewage smell
« Reply #17 on: October 16, 2013, 02:22:41 PM »
Maybe something died after you had the furnace inspected and the ducts clean. Mice will try to eat through anything such as a filter and die in the process. You could have a dead mouse in your filter. If there is a hole in the filter then you know something has been there.

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #18 on: October 16, 2013, 05:20:56 PM »
Maybe something died after you had the furnace inspected and the ducts clean. Mice will try to eat through anything such as a filter and die in the process. You could have a dead mouse in your filter. If there is a hole in the filter then you know something has been there.
We just put a new filter in a week ago. And the smell is definitely sewage smell, not natural gas, not death.

The weird thing is the smell is intermittent. It will sometimes blow with no smell at all, sometimes it will blow a few seconds without smell and then get stinky.

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #19 on: October 21, 2013, 08:23:45 AM »
Ugh. I broke down and called the plumber to come later today. Cross your fingers, I hope this person can figure it out. After 3 or 4 days without smell, we had it again this morning. Then, misteriously, it has stopped again the next few times the heat kicked in. WTF?

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #20 on: October 21, 2013, 01:02:34 PM »
Oh shit. The plumber thinks it's a cracked or otherwise defective pipe near the basement drain, but he thinks the drain itself is fine. When the furnace kicks in, it draws air in from the pipe through cracks in the floor (he thinks that's where the smell is coming from), and in order to fix that they have to open up the concrete floor to find the problem. Cost: $3000 estimate. OUCH!

Kevan

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Re: Dumbfounded by sewage smell
« Reply #21 on: October 21, 2013, 04:29:40 PM »
You need a second opinion.

And if it comes down to actually jackhammering the basement floor, it's a low-skilled task. Rent an electric jackhammer from Home Cheapo for $50 and have at it.

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #22 on: October 22, 2013, 12:45:27 PM »
We are definitely getting a 2nd opinion. My confidence in this Master Plumber's "mastery" was very low.

Spork

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Re: Dumbfounded by sewage smell
« Reply #23 on: October 22, 2013, 01:04:56 PM »
Can someone scope it with a camera before you go all nuclear on the floor?

If the area is small... you can even get by without a jackhammer. A circular saw or an angle grinder with a masonry blade will make a clean edge... then you can drill holes with a masonry bit -- even better if you have a hammer drill. Pound with sledge.... done.

I've done several square feet like that ...but I wouldn't want to do a large area that way. And there WILL BE DUST... OHMYGOD THERE WILL BE DUST.
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SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #24 on: October 22, 2013, 07:56:41 PM »
This guy said it's not possible to scope it. The pipe is too small.

This does NOT sound like a job I want to DIY (if it's really the problem). At all. I have no skills in this area, and even if I did jackhammer it open and miraculously managed to do so without breaking anything else (I'm a female with not much brute force and I don't think I could even wield that monster safely), I wouldn't know what to look for underneath and much less how to fix it. Sorry, folks, but I will be dipping my toes in different DIY waters first.

Kevan

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Re: Dumbfounded by sewage smell
« Reply #25 on: October 22, 2013, 09:14:51 PM »
Indeed, a jackhammer is a large, heavy, unwieldy behemoth -- not for ladies or ladylike men.

Personally, I'm having a hard time picturing a way for the plumber's diagnosis to be correct. So I doubt it.

Greg

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Re: Dumbfounded by sewage smell
« Reply #26 on: October 23, 2013, 07:53:09 AM »
This theory about the damaged pipe can be tested. A plumber (or even a homeowner) should be able to fish a bladder down the pipe past the suspected damaged area, inflate it and therefore block the drain/pipe. Then, you can fill the pipe via the drain to see if it holds water. If the water drains out, it's safe to assume the pipe is damaged.

I would not dig up any floor drains without testing myself. I still suspect the trap in the floor drain may be rusted out or otherwise damaged.

paddedhat

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Re: Dumbfounded by sewage smell
« Reply #27 on: October 23, 2013, 07:57:13 AM »
This guy said it's not possible to scope it. The pipe is too small.

This does NOT sound like a job I want to DIY (if it's really the problem). At all. I have no skills in this area, and even if I did jackhammer it open and miraculously managed to do so without breaking anything else (I'm a female with not much brute force and I don't think I could even wield that monster safely), I wouldn't know what to look for underneath and much less how to fix it. Sorry, folks, but I will be dipping my toes in different DIY waters first.


This guy is full of shit and playing you as a fool. I did a 30 second search and found a sewer camera snake that is 10M long (about 33') and 14.5 MM wide (about 5/8") for 22 bucks, AND it can be plugged into your laptop. Believe me, the sewage laterals under your slab are a plenty big enough for a 5/8" diameter camera.

As for his diagnosis, he may be correct. Run that heat and get on the floor, see if YOU can smell a very well defined sewage smell, coming out of a seam or crack, at a specific location? I had a very similar situation recently with a vent line that was. fortunately, far more accessible and repairable. First, I would head to the Home Depot and get a few tubes of "Sika-Flex" Urethane caulk for concrete joints. Now throw some disposable gloves on, and start caulking all cracks and joints in the vicinity of the alleged defect. Problem go away? Well then the plumber was right. Now you need to find a reasonable way to scope the pipe to determine exactly where the issue is, and them jack out that specific area for a repair. This should be a few hundred bucks in repair, not $3K. As for a jackhammer, you need to take a look at an electric hammer drill with a demo tip on it. They are 1/4 the size of an electric jackhammer and will do just fine if you can clearly locate the supposed break prior to randomly hacking away at the basement floor. Find some help, and give it a shot, you can do it!

Spork

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Re: Dumbfounded by sewage smell
« Reply #28 on: October 23, 2013, 09:14:53 AM »
This theory about the damaged pipe can be tested. A plumber (or even a homeowner) should be able to fish a bladder down the pipe past the suspected damaged area, inflate it and therefore block the drain/pipe. Then, you can fill the pipe via the drain to see if it holds water. If the water drains out, it's safe to assume the pipe is damaged.

I would not dig up any floor drains without testing myself. I still suspect the trap in the floor drain may be rusted out or otherwise damaged.

This.

We had some SIGNIFICANT plumbing problems (think of a Hogan's Heros style tunnel in the living room). Before digging that... and after repairing it, they pressure tested the whole house. There was an air bladder at the sewer exit and in every vent stack and they pressured it with air to see how long it would hold. Smaller sections can be done to narrow down where the leak is (assuming there is some idea how the plumbing is run).
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SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #29 on: October 23, 2013, 11:39:05 AM »
Ok, I'm pretty sure the plumber's diagnosis is wrong, and so is my initial one as well. Here's why. Upon Sherlock's closer investigation...

Just now, the heat was not blowing. I felt the smell coming from the air intake in the hallway for the furnace, tho. I unscrewed the cover, and sure enough there's a pipe running in there, 99% sure it's a sewage pipe. I couldn't stick my head in there but I was able to stick my hand with my phone in there and took these pictures (one looking towards bathroom, one looking towards where the pipe runs down to the basement). I don't see any actual sewage leaks, but if my thinking is correct, this section of pipe may be leaking sewage gas/smell somewhere into the air that's being sucked in by the furnace from the house, which then gets redistributed through all the vents into the whole house.

Edit: Also, I stuck my nose right by the drain in the basement floor and by the cracks in the basement floor and smelled no sewage, even while the smell was coming out of that intake upstairs. All I smelled was the previous owners' cats' odor (their litter box used to be right there in that utiltity room), so that may be what the plumber smelled and thought it was sewage.

What do you all think? And if I'm right... How to find the leak and fix this inaccessible pipe?



« Last Edit: October 23, 2013, 11:49:10 AM by worldstrad »

ScottEric

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Re: Dumbfounded by sewage smell
« Reply #30 on: October 23, 2013, 12:21:04 PM »
That looks like Black ABS waste pipe to me, you might be onto something there!

What plumbing fixtures do you have that are above where you took the picture? What would both ends of that hook up to? It's hard to tell how large that pipe is from the pictures, so it could be a big main branch or a smaller 1.5 or 2 inch branch pipe that serves a fixture or two.

Scott

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #31 on: October 23, 2013, 12:40:39 PM »
That looks like Black ABS waste pipe to me, you might be onto something there!

What plumbing fixtures do you have that are above where you took the picture? What would both ends of that hook up to? It's hard to tell how large that pipe is from the pictures, so it could be a big main branch or a smaller 1.5 or 2 inch branch pipe that serves a fixture or two.

Scott

This pipe is probably about 4 in. According to the location, it would be the main branch going away from the upstairs bathroom. It runs down towards the basement right where that curved joint is, probably hooking into the main line under the basement floor right by that floor drain in the utility room, is my guess.
« Last Edit: October 23, 2013, 12:52:42 PM by worldstrad »

Spork

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Re: Dumbfounded by sewage smell
« Reply #32 on: October 23, 2013, 12:54:34 PM »
I think you're onto something.

I don't know code ... but I'm guessing this is a no-no. I see what looks to be electrical and plumbing in there... And it's hard to tell, but it almost looks like the return has been cut into and there are roughly cut ends of 2x4s (or something) in there. Am I seeing that right?

Is this air return (relatively) air tight? I'm going to guess no. I'm going to guess you're also pulling air from uninsulated space into there in addition to the lovely sewer gas.
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Greg

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Re: Dumbfounded by sewage smell
« Reply #33 on: October 23, 2013, 01:06:07 PM »
OK, my new theory on this is that the union in the second image, the one that shows the downturn, is not air/water tight. Or, one of the elbows at the downturn. The union has some funkyness visible at the top of the joint. Is the light area under the pipe dust or leftover from effluent evaporating?

Either way you have some options... if you can reach the union, get some self-vulcanizing repair tape, sometimes called emergency tape, and tape up the joint. If the pipe is black plastic, ABS, you could slather some pipe cement over the joint.

The best option is to access the area and repair/redo the joint. 4" is hard to cement together so it could have been this was since it was installed, if plastic. If it's cast iron or galvanized steel it could have gone bad over the years, corrosion etc.

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #34 on: October 23, 2013, 01:44:18 PM »
Greg, there was some dust, but if that's all it was, I'm not sure. I didn't see anything wet right now, but it could be old stuff I guess. Just not sure. I can see very little with my own eyes, like I said I had to rely on the camera to even show me this much. I'm guessing joints/elbows as the source of the problem, too. It definitely is black ABS.

Now, I'm second guessing myself that this is a duct though... where does it go??? Though this has GOT to be it, since I don't see other returns. Spork, it would not be pulling air from uninsulated areas. The wood you see are the floor planks/joists of the main floor. It's probably not airtight, but it would be pulling air from conditioned space on the main floor. It looks closed on one end, and at the other end I can't see behind the pipe. When the duct cleaners came, my partner says she thinks they cleaned in there (if that's true, maybe THEY messed something up by bumping the pipe?).

All I can say is this, tho tricky, seems a lot less dramatic than breaking the basement concrete floor open.

Spork

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Re: Dumbfounded by sewage smell
« Reply #35 on: October 23, 2013, 01:48:16 PM »
You could turn the HVAC fan on and put some smoke in there to see where it goes. (A blown out candle or match.)
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Re: Dumbfounded by sewage smell
« Reply #36 on: October 23, 2013, 10:13:17 PM »
Since it's ABS, if you can reach the union (joint visible in the straight run), buy a large can of ABS cement (large can = large brush) for a few $$ and reach in with it and coat the union joints with cement. Top, sides, bottom, both ends. Don't worry about spills in the chase. This will be a different kind of stinky for a day or so. See if it helps.

If it's beyond reach, can you open a hole in the bottom of the chase under the union? Anything you cut (except the pipe and wire, obviously) can be repaired. Once open, do the above and see if it helps.

I'm a designer and contractor and have found un-cemented joints in remodel work, so anything's possible.

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #37 on: October 24, 2013, 05:29:34 PM »
I really can't reach the union. The opening is at a really bad angle and not very big. I'll have to investigate options. Thanks guys!

paddedhat

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Re: Dumbfounded by sewage smell
« Reply #38 on: October 25, 2013, 08:34:12 AM »
Couple of points of information here. You have taken a pic. of a "panned joist bay". The tin you see is used to close the bottom of the joist bay, and create a return duct to the furnace. Plumbing and wiring are technically not acceptable in this space, for fire safety reasons. That said, it isn't the first time anybody panned a bay with other mechanicals in it, and I wouldn't worry about that issue. Second there is no "union" involved here. Unions are removable connections that are specifically designed to allow for disassembly of a mechanical connection, you don't have on in these pics. You are looking at a standard 90* ABS DWV fitting and perhaps a 22* fitting attached to it. ABS is the material, as opposed to PVC, DWV is the pipe designation, and it stands for drain, waste, vent. It can only be glued with an ABS specific glue, and it does not need a primer. I doubt that it is 4" pipe, probably 3" which would be 3-1/2" O.D.

This may be a pretty simple fix. you need to remove piece of the tin pan to access the area. It is probably nailed thoroughly, and excessively, with roofing nails into the bottom of the joists. You can repair the area using the same material and techniques. Tin, and metal foil duct tape are readily available at Home Depot. Once you access the pipe, you may encounter a glued joint or fitting that was originally assembled dry, as in the installer forgot to glue it. Twist and bang on everything. to see if anything is improperly assembled. The other thing to look out for is that some ABS pipe will fail with age, by splitting at the seams. This may be a bit tougher to spot, as it will be a nearly microscopic, but very straight clean split in the pipe, running the length. The cure for this can be as simple as wiping the area clean and using ABS glue as caulk. Good luck, nice sleuthing so far. BTW, A neighbor just ran into this exact issue when some of the 20 Y.O ABS drain lines started to split open at the joints. I don't know how prevalent of an issue it is? But it certainly is possible that this is your problem.

Greg

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Re: Dumbfounded by sewage smell
« Reply #39 on: October 25, 2013, 09:22:00 AM »
The second pic clearly shows a joint between two straight lengths of pipe. You're right though, the part joining the straight lengths is called a coupling, not a union, my mistake. :)

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #40 on: October 25, 2013, 11:16:19 AM »
Couple of points of information here. You have taken a pic. of a "panned joist bay". The tin you see is used to close the bottom of the joist bay, and create a return duct to the furnace. Plumbing and wiring are technically not acceptable in this space, for fire safety reasons. That said, it isn't the first time anybody panned a bay with other mechanicals in it, and I wouldn't worry about that issue. Second there is no "union" involved here. Unions are removable connections that are specifically designed to allow for disassembly of a mechanical connection, you don't have on in these pics. You are looking at a standard 90* ABS DWV fitting and perhaps a 22* fitting attached to it. ABS is the material, as opposed to PVC, DWV is the pipe designation, and it stands for drain, waste, vent. It can only be glued with an ABS specific glue, and it does not need a primer. I doubt that it is 4" pipe, probably 3" which would be 3-1/2" O.D.

This may be a pretty simple fix. you need to remove piece of the tin pan to access the area. It is probably nailed thoroughly, and excessively, with roofing nails into the bottom of the joists. You can repair the area using the same material and techniques. Tin, and metal foil duct tape are readily available at Home Depot. Once you access the pipe, you may encounter a glued joint or fitting that was originally assembled dry, as in the installer forgot to glue it. Twist and bang on everything. to see if anything is improperly assembled. The other thing to look out for is that some ABS pipe will fail with age, by splitting at the seams. This may be a bit tougher to spot, as it will be a nearly microscopic, but very straight clean split in the pipe, running the length. The cure for this can be as simple as wiping the area clean and using ABS glue as caulk. Good luck, nice sleuthing so far. BTW, A neighbor just ran into this exact issue when some of the 20 Y.O ABS drain lines started to split open at the joints. I don't know how prevalent of an issue it is? But it certainly is possible that this is your problem.

Thank you so much for all the correct nomenclature. That was very helpful as I now know more about what I'm dealing with here.

3 1/2" OD sounds right, that 4" was just a guess without measuring. The panned joist bay may still be difficult to access as below there is a finished basement with ceiling, so the tin is not directly accessible from the bottom. I guess a hole will have to be cut into the ceiling to get to it.

paddedhat

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Re: Dumbfounded by sewage smell
« Reply #41 on: October 25, 2013, 05:04:41 PM »
3 1/2" OD sounds right, that 4" was just a guess without measuring. The panned joist bay may still be difficult to access as below there is a finished basement with ceiling, so the tin is not directly accessible from the bottom. I guess a hole will have to be cut into the ceiling to get to it.

Well that sucks. I would now try to drill a very large (4" or so) hole through the ceiling and tin, just adjacent the joint. This is real easy to patch, and will give you a hand hole to access the area. Remember a hole saw that big can really toss you around, you need a strong 1/2" drill with two handles. Hold on tight, and don't drill the drain pipe. Unfortunately, my guess is that you are suffering from a failed seam, and that will require some extensive demo. to get to the pipe. If you get to the point that you have to replace a section of pipe, you may want to Google "Fernco" couplings. These are rubber sleeves that allow you to chop a section of pipe out and replace it with just a hand saw and a screwdriver.

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #42 on: November 11, 2013, 05:48:28 PM »
Just had the house smoke tested and after sawing open the drywall in the laundry room where smoke was billowing out, found an uncapped sewer vent pipe behind the wall, right underneath the panned joist bay of the return air duct of the furnace. Smoke was making its way into the return furnace through the cracks.

Also saw a little bit of smoke coming from cracks in the floor cement near that floor drain... But I don't think that is the main issue.

Guy recommended getting what he called a "gem cap" and closing that vent pipe. Is that correct advice? Would that cause any other problems? There is another vent pipe running right next to it, turns out that's the one that goes up into the return duct (he says it's not an actual sewage pipe, but a vent pipe). He said they both seem to come from the washer.

fidgiegirl

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Re: Dumbfounded by sewage smell
« Reply #43 on: November 11, 2013, 06:04:20 PM »
May need to get rotor rooter to clean.

I think that is an inexpensive method to try as I have done the same in the past but before you do that read the following article. It's a story about how a gas line was retro drilled through the sewer and the house ended up exploding when a rotor rooter was used to unclog it.

http://minnesota.publicradio.org/display/web/2010/03/11/gas-line-inspections

That was in our area, and they've been inspecting and redoing all the lines for years because of it.

paddedhat

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Re: Dumbfounded by sewage smell
« Reply #44 on: November 11, 2013, 08:00:13 PM »
Hey, I learned something today. Had to google "gem" cap. It is what we call a "Fernco" cap in these parts (see my last post here) Nothing but a very substantial rubber cap with a built in band clamp. This would seal the pipe, but..... and remember, there is always a but. Your washer needs to be properly vented. The reason is that it violently discharges drain water while in the drain cycle. It is possible that, in the absence of proper venting it will blow the trap dry as the drain cycle abruptly stops. This will create, oddly enough, another source of odors. In this case you could prevent this with a
cap known as a "Studor valve" or a cheaper product called an "Air Admittance Valve" Both of these allow air to vent into the system, but not out. Now the next issue is that they technically need to be accessible for servicing, since they do in fact, eventually fail. They work using a thin rubber flap as a one way valve, allowing air to enter the pipe, but not exit. So, you decide how to proceed. A Gem cap is dirt cheap and worth a shot. A Studor valve is the right thing to do. Replumbing the vent so that the end is exposed, and a few feet high than the washer, and capped with a Studor valve, would clearly make you the envy of plumbers, worldwide. Go forth and tackle this job, grasshopper, your fellow 'staches are proud.

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #45 on: November 11, 2013, 08:20:17 PM »
Hey, I learned something today. Had to google "gem" cap. It is what we call a "Fernco" cap in these parts (see my last post here) Nothing but a very substantial rubber cap with a built in band clamp. This would seal the pipe, but..... and remember, there is always a but. Your washer needs to be properly vented. The reason is that it violently discharges drain water while in the drain cycle. It is possible that, in the absence of proper venting it will blow the trap dry as the drain cycle abruptly stops. This will create, oddly enough, another source of odors. In this case you could prevent this with a
cap known as a "Studor valve" or a cheaper product called an "Air Admittance Valve" Both of these allow air to vent into the system, but not out. Now the next issue is that they technically need to be accessible for servicing, since they do in fact, eventually fail. They work using a thin rubber flap as a one way valve, allowing air to enter the pipe, but not exit. So, you decide how to proceed. A Gem cap is dirt cheap and worth a shot. A Studor valve is the right thing to do. Replumbing the vent so that the end is exposed, and a few feet high than the washer, and capped with a Studor valve, would clearly make you the envy of plumbers, worldwide. Go forth and tackle this job, grasshopper, your fellow 'staches are proud.

Thanks, paddlehat, for your input. That pressure problem is exactly what I was worried about that could happen, and I was wondering if the Studor valve wouldn't be better (I just didn't know the name for it). How are those installed? If I were to reroute the DWV pipe, how are the fittings put together? Special glue? I would have to get an elbow and a piece of straight to stick out the wall.

Greg

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Re: Dumbfounded by sewage smell
« Reply #46 on: November 12, 2013, 10:06:26 AM »
Another option is to install the Studor vent onto the vertical pipe, and install an access panel in the drywall so it can be serviced.

SavingMon(k)ey

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Re: Dumbfounded by sewage smell
« Reply #47 on: November 12, 2013, 10:51:56 AM »
Another option is to install the Studor vent onto the vertical pipe, and install an access panel in the drywall so it can be serviced.
Ah, brilliant. I was thinking just leaving a hole in the wall, but that's just not classy. How do I repair the huge drywall holes??? Any good resources? I can't access YouTube from work. :(

Edit: my other problem is the pipe needs to be shortened a bit for me to be able to fit a threaded fitting on top. How the heck do I saw a pipe that's in a wall? I can't fit a hacksaw in there. Dremmel? (I don't have one). Also, since the pipe is 3 1/2" OD, do I ask for a fitting and a Studer valve for a 3" pipe?
« Last Edit: November 12, 2013, 10:59:57 AM by worldstrad »

Greg

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Re: Dumbfounded by sewage smell
« Reply #48 on: November 12, 2013, 11:23:52 AM »
If it's a plastic pipe, use a cable saw, available in the plumbing tools section of your local hardware store. Most studor vents are made to fit 1-1/2" pipe, so you'll have to adapt down to that size and then install. The ones I've seen are sold with male threads, so get the appropriate female threaded fitting to install it to. You could also use a fernco fitting to adapt to the smaller size.

You can get a snap-in plastic cover for the service opening, they come in a few sizes.

For other drywall holes, I usually use small pieces of plywood screwed to the surrounding drywall to support the patch section, then tape and mud the repair joints.

paddedhat

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Re: Dumbfounded by sewage smell
« Reply #49 on: November 12, 2013, 07:22:27 PM »
Greg has some good ideas here. A cable saw is a nice thing to have, but you can also do the job with a piece of strong nylon string, like mason's line. The access panels are really nice looking when installed, you just butter the back of the flange with construction adhesive, and temporarily brace it in place until the glue sets. Hopefully this is not the 3-1/2" pipe that is the open vent pipe? Typical washer vents are 2". A 3" Studor is expensive, probably too large to fit in a typical stud bay, and might starve for air tucked inside a wall.