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Sewer odor

arellanogg | Posted in General Discussion on February 6, 2009 06:52am

I just finished building my house. We started to smell a bad odor but I thought it might carpet etc….. needless to say it was a Air admittance valve, that was under our kitchen sink. It had failed and had been venting sewer gas into our house. I replaced it and left the outside doors open all day. I kept smelling it and have come to discover that the smell is in the heat and air ducts. Is there a way to get that smell out… or will it just be a matter of time.

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Replies

  1. User avater
    IMERC | Feb 06, 2009 06:56am | #1

    got a basement???

    where is the air return???

    any floor drains...

    city or ceptic sysyem???

    make sure all the traps in the sinks, tubs and floors ar filled....

     

    Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming

    WOW!!! What a Ride!


    Forget the primal scream, just ROAR!!!

     

    "Some days it's just not worth chewing through the restraints"

    1. arellanogg | Feb 06, 2009 07:07am | #2

      We are on a septic tank... I found the source of the sewer gas leak is was the air admittance valve under the kitchen sink... but its like the return air duct has absorbed the smell and now they just stink. will this be just a matter of time for the smell to wear off?

      1. Scott | Feb 06, 2009 07:10am | #4

        Have you left the fan going? It shouldn't take long to clear itself out if you let it run for a while.Scott.

      2. User avater
        IMERC | Feb 06, 2009 07:12am | #5

        sounds unusual...

        and the order should dissipate over time...

        in the mean time I'd go looking for another "odor'' source... 

        Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->

        WOW!!! What a Ride!

        Forget the primal scream, just ROAR!!!

         

        "Some days it's just not worth chewing through the restraints"

        1. arellanogg | Feb 06, 2009 07:19am | #6

          I will look for another source, while holding on to the hope that that was it and the smell will go away.

          1. TomW | Feb 06, 2009 08:06am | #7

            Are the traps at all the sinks full of water? How about the washer drain?

          2. levelone | Feb 06, 2009 08:07am | #8

            Teenage boys--dirty socks?

          3. calvin | Feb 06, 2009 02:55pm | #10

            Try placing a couple pans of white vinegar near the air returns, put the fan switch to "on" at the thermostat.

            Helps for oil based paint smell.

            Of course the house smells like a salad for a few hours.A Great Place for Information, Comraderie, and a Sucker Punch.

            Remodeling Contractor just outside the Glass City.

            http://www.quittintime.com/

             

          4. Mooney | Feb 06, 2009 05:15pm | #20

            "Teenage boys--dirty socks?"

            We had a case of discovery last night .

            Seems he had been wearing his socks all week. For what reason is unclear . He says he doesnt know why he doesnt change his socks when he takes a shower . Bill Cosby says its brain damage.

            Tim  

          5. User avater
            popawheelie | Feb 06, 2009 08:08am | #9

            I had a smell in my bathroom. The "handy" previous owner had used plaster of paris to form a seal between the flange and the toilet.

            It had been soaking for years.

            I pulled everything off, washed the area with ammonia, and put down a wax seal.

            It took a month for the smell to go away.

            Some people don't put down wax seals properly. I think it's fairly common.

            The toilet can't rock. I've pulled up toilets many times that show that the wax seal wasn't completely in contact all the way around.

            I'm very careful that wax rings make full contact on a clean dry surface on the flange and the toilet.

          6. Clewless1 | Feb 07, 2009 05:38am | #35

            Sewer gas smell should not 'cling' to return air ductwork ... makes no sense really. It's not like its an absorbant material (unless it is e.g. fiberglass duct board). You shouldn't have issues w/ smell. It should be gone in hours.

          7. DanH | Feb 07, 2009 06:38am | #36

            I'd agree. Something else is smelling.
            The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith

          8. rich1 | Feb 12, 2009 07:45am | #46

            "I'd agree. Something else is smelling."

             

             

            Sooooooooooooo............ I'm doing a furnace inspection.

            "Ma'm, are you missing a pet?"

            "Our ferret has been missing for about a month, why?"

            "What's left of it is in the furnace fan.  You want the fur and bones?"

          9. atrident | Feb 07, 2009 06:44am | #37

             It should go away quickly. I had a similar problem. Turned out to be the propane torch I borrowed from my neighbor to do some soldering." Yeah it leaks a bit when its turned off "he says. Only way I found it was cuzz the propane tank was about empty when I picked it up. I put visqueen around the toilet and let it sit for awhile and stuck my head under there and sniffed...nope. I cut open a 2" vent pipe to see if I left the rag in there...nope. Took a couple of days till I finally moved the torch that was sitting on the water heater.

          10. User avater
            popawheelie | Feb 12, 2009 08:11pm | #49

            Funny stuff! You ever let someone borrow your torch and it comes back real tight?

            And that is from guys who are supposed to know better.

      3. user-102795 | Feb 07, 2009 10:54am | #38

        There seem to be quite a few responses to your original question which you have not yet read... that can make it hard to know what an appropriate response to your question might be.Do you use well water? You indicate the presence of a septic system....If you have a well, there is a chance that there are bacteria in the well water (introduced during the drilling operation?) which oxidize various minerals in the water (I don't remember specifically which), and which, in the process, give off gases which have a sulfurous smell, somewhat like sewer gas. These gases permeate the whole house, and can be most annoying, to say the least. Like you, we had a similar odour problem in our new home, which should have smelled like fresh wood, but smelled of decaying you know what.... After a lot of questioning (and a couple of years of bewilderment that no one would have any idea what the problem was), we decided to try one solution that was eventually suggested – "shock" the well. The process is simple; it involves disinfecting the well (killing the bacteria) by pouring down a good volume of water containing bleach, which kills the offending bacteria. Check this website:http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex1142Here you will find details on how to proceed. While the website talks about the need to "shock" the well to eliminate iron-oxidizing bacteria, the process also eliminates the issue of sulfur bacteria, and may be the solution to your problem.Of course, if you are on a city water-distribution system, this is totally irrelevant :)Good luck!Tedbeen there, done that, etc., etc,

        Edited 2/7/2009 3:24 am ET by old baldy

    2. User avater
      nater | Feb 06, 2009 08:44pm | #26

      Drop a couple smoke bombs in the septic tank, see where smoke comes out.

  2. FramerTK | Feb 06, 2009 07:10am | #3

    The smell should go away over time. Sewer gas is kind of like a fart - it should pass fairly quickly. I think you still have a leak somewhere. We had a similar problem, plumber replaced the air valve and we still had the problem. After he replaced the wax rings on 3 out of our 5 toilets the problem went away.

    1. dejure | Feb 08, 2009 11:24am | #41

      It seems the gassing would have been intolerable to still be lingering long enough for our posts back to matter, after the repair was made. If it lingered, I would, as others have suggested, certainly not rule out additional problems. That could be anything from those things already mentioned to a broken or cracked pipe. I was amazed to see what a hairline crack in pipe would allow to pass. Had one out in the field by the well and, until the section was replaced (found it by accident), we always got up 1/8" of silt in a five gallon bucket of water.In a pinch, you could use an ozone machine, but they shouldn't be ran while you are in the house (and air should be vented off before reentering). If you have drains that sit unused for long periods, the water in the trap evaporates and you no longer have a trap. You can put a few spoonfuls of vegetable oil in the drain to slow down evaporation, or just remember to run water down the system every few weeks.

  3. DanH | Feb 06, 2009 03:42pm | #11

    Let me be the first to say that it was foolish to use an air admittance valve in new construction.

    The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith
    1. User avater
      IMERC | Feb 06, 2009 03:59pm | #12

      not when they're used in conjuction with a dish washer.... 

      Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->

      WOW!!! What a Ride!

      Forget the primal scream, just ROAR!!!

       

      "Some days it's just not worth chewing through the restraints"

      1. DanH | Feb 06, 2009 04:06pm | #13

        Never heard of one being used with a dishwasher. How so?
        The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith

        1. User avater
          IMERC | Feb 06, 2009 04:34pm | #17

          AHJ.... 

          Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->

          WOW!!! What a Ride!

          Forget the primal scream, just ROAR!!!

           

          "Some days it's just not worth chewing through the restraints"

          1. Mooney | Feb 06, 2009 05:34pm | #21

            When you visted me here it was against plumbing code and was only allowed by me in special circumstance.  [AHJ] I actually got an hour class on it so it must have been a big deal to them. I only ran across one and rejected it . A plumber had used one on a washer but it was tied to the sewer. I could have approved one on an island or a dishwasher if a wet trap followed it and there was no other way. Theres supposed to be a wet trap made of the discharge line it self at least . That actually came up over dishwashers to review the code becuase we were taught to accept maufactures specifications. There was supposed to be a company selling dishwashers that had one included and told them to "trap " the discharge line with a devivce they send along with it . I ran across a company that directed the line to be ran right under the counter top which of course was higher supplying its own trapping system. They were spupposed to include checking with their local plumbing codes before installing was the aggreement they came to . It actually forced us to approve it if their was no other way.

            Thats the story as I know it . Pumbing codes never "wanted " to approve it .

            Tim  

    2. User avater
      Matt | Feb 06, 2009 04:08pm | #14

      >> Let me be the first to say that it was foolish to use an air admittance valve in new construction <<  Sometimes they are necessary - like for a kitchen sink on a island or on a peninsula.   I have my plumber under the orders of "No AAVs without prior approval of the builder".  Sometimes these guys get lazy and just want to take the easy way out.  Personally, I always try and avoid using AAVs.

      1. DanH | Feb 06, 2009 04:18pm | #16

        They can be avoided even in an island.
        The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith

        1. User avater
          Matt | Feb 06, 2009 04:59pm | #18

          They can be wet vented, but here our plumbing code only allows a wet vent of a certain max length - not sure what it is - maybe 5'. 

          Maybe that was what IMERK was insinuating.  Sometimes he might be a little too concise. :-)

          Here, nearly every island sink is studor vented.  Maybe if the island was adjacent to a blank wall rather than appliances or other base cabinets like they normally are.

          I've seen pictures of those loop vents, but never have actually seen one in a house - I think it is just another flavor of a wet vent... Anyone know?

           

          1. DanH | Feb 06, 2009 07:29pm | #22

            A loop vent isn't "wet".
            The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith

          2. User avater
            Matt | Feb 07, 2009 03:18am | #28

            Got a pic?  LIke I said, I don't know much about loop vents.

          3. DanH | Feb 07, 2009 03:42am | #29

            Nope. I've seen diagrams but don't know where to find one online.
            The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith

          4. User avater
            Matt | Feb 07, 2009 04:55am | #31

            I went and googled loop vent and found the attached.  You are right - it isn't a wet vent.

          5. mike_maines | Feb 07, 2009 04:53am | #30

            View Imagehttp://lh6.ggpht.com/_E9v6ewMEgpk/R8HzWsPqKTI/AAAAAAAAAqs/aDbPiI4zhv8/DSC_0179.JPG

          6. User avater
            Matt | Feb 07, 2009 04:56am | #32

            pic didn't come through.  I found one though.... 

          7. JeffinPA | Feb 08, 2009 06:57pm | #43

            If i recall properly, the IRC code book illustrates how to vent an island drain with oversized trap and drains.   I believe you need to upsize everything 1 size and then S trap or P with  short arm to drop.  (I dont remember exactly)

            I never see AAV's in new construction around these parts and most inspectors make you run a vent if there  is any possible way to run a vent prior to accepting aav.

          8. User avater
            Matt | Feb 11, 2009 03:58pm | #44

            Can you give us some details about venting of kitchen island sinks?

             

          9. plumbbill | Feb 11, 2009 06:35pm | #45

            The "loop vent" pic that you posted is almost correct.

            You do need to use a drainage fitting (combination wye & 1/8th bend) where the horizontal vent (foot vent) meets the vertical vent below the cabinet.

            Here's a pic from the UPC training manual that explains each section.

            View Image

             

          10. User avater
            Matt | Feb 12, 2009 03:43pm | #47

            Thanks Bill.  I wonder if there has to be a certain vertical distance between the horizontal (under floor) vent run and the horizontal waste pipe shown below it in the pic?  Also, I wonder if that is gonna work with a slab house?  

             

          11. plumbbill | Feb 12, 2009 06:25pm | #48

            Just like any other vent it has to come off the top half of the waste pipe.

            & yes that can go underneath slab on grade.

             

          12. User avater
            Matt | Feb 18, 2009 04:29pm | #50

            I showed the island loop vent diagram you were so kind to post to my plumber.  He said the only time he had ever installed one of those was on commercial jobs and that that couldn't be used with the slab houses I'm currently building because of the cleanout location requirement.  Maybe the cleanout could be turned up to the floor surface?  Maybe it really doesn't have to be right there.... About 70% of what I build are slab homes, with only a few island sinks - and they had AAVs.  After I thought about it I kinda wondered.... aren't most commercial jobs slab construction....

            Then the plumber proceeded to give me the sphiel about different brands of AAVs and said that he uses Oatey Sure Vent AAVs because he feels they are the best and most reliable.

            Later this week I have some plumbing inspections so I'll show the plumbing inspector the diagram if I see him and see what he has to say about it.

            Here is what I don't get though.  Above they said there is never a reason to use AAVs on new construction, which is what I'm trying to find out about.  I guess that is insinuating that AAVs are sometimes OK on other than new construction?  I don't see that...

            Also, I looked in our plumbing code book and it talked about up-sizing waste pipes for island installations but didn't mention the loop vent.  Maybe the plumbing inspector will answer that too.

          13. plumbbill | Feb 18, 2009 06:33pm | #51

            We rarely put the cleanout on the bottom as the pic shows, cause that would usually end up being in the condo below the island sink.

            We put the cleanout on the vertical waste pipe below the san-tee & above the floor line. Here is a pic of what that would look like.

            http://www.theplumber.com/images/island.gif

            View Image

            To my knowledge NC goes by the IPC which loop vents (AKA special venting for island sinks) are legal.

             

          14. User avater
            Matt | Feb 19, 2009 05:20am | #53

            Thanks... makes sense.

          15. klhoush | Feb 19, 2009 08:07pm | #54

            I once built a "double " loop vent to get a basement addition vented. The sewer pipe was far away so by the time I got to the toilet the main line was close to the bottom of the joists.  The foot vent hit the floor joists before the stack so I built a second loop.  The inspector thought it was a reasonable solution to the problem.

            When I think back on my career, I figure I should move and leave no forwarding address before someone figures out what I've been doing.

            OB

          16. User avater
            Matt | Feb 27, 2009 04:03pm | #55

            I finally got up with a plumbing inspector.  He likes to talk...

            He said that our NC plumbing code (modified IPC) does not specifically allow loop vents - or utility vents as he called them.  He said he would allow one as an "alternative method" but only with prior approval, and underlined strongly that if I wanted to do this to get whatever inspector was involved to OK it ahead of time.  He said he would want the bottom waste line to be a 3" and the associated cleanout to be 3".  He also said he felt that it was a reasonable solution for venting a island (or similar) sink and that he would use it in his house (if he were building one).  OTOH, another plumbing inspector who wanted to go by the NC plumbing code could require an AAV. 

            During our conversation (again, he likes to talk) he gave me a few rules of thumb which I thought were really good info:  1) No pipe under a slab can be smaller than 2".   2) Per the NC plumbing code, a sink can never be wet vented.   Showers and tubs were OK to wet vent.  (maybe some other fixture that I am not recalling right now)   3) any cleanout has to be sized the same as the main waste pipe it services so that a cleaner head (or whatever they are called) of the appropriate size can fit into the cleanout.  This one is common sense but sometimes a non-plumber like myself may not think of it.  So for the loop vent with a 3" waste line he would want 3" cleanouts.  Part of the reason I included this paragraph was to help myself remember the info.

            I also got my hands on a plumbing code book (for a few minutes).  The island vent stuff is dealt with in section 913 and specifically, paragraph 913.3  which says "The vent  located below the flood level rim of the fixture being vented shall be installed as required for drainage piping in accordance with chapter 7.  Wish I had a scanner to show the Page I got the lady at the code book store to Xerox, although it looks like the full text might be on this web page.  I couldn't really ask her to Xerox all of chapter 7...  There didn't seem to be any NC modifications to that paragraph 913.3.

            In summary here is what I think...  The statement above about new construction never needing AAVs got me thinking and based on some research I did I learned something about loop vents and wet vents, which was supported and clarified by our resident plumbing expert Bill.  Thanks Bill!  OTOH, the few guys above who made the statement that AAVs were never necessary in new construction (paraphrased) don't build houses, and were just making unsupported statements.     

          17. DanH | Feb 19, 2009 02:29am | #52

            I'm not that familiar with plumbing code, but there are several of cases where electrical code makes exceptions for "old work" -- cases where wires must be fished down an existing wall, etc.   For instance, the requirement to staple the wire every so many feet is eliminated (for obvious reasons).  With plumbing one big problem when working with existing construction is routing vents, so there is more reason to allow AAVs.
            The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith

    3. JeffinPA | Feb 08, 2009 06:52pm | #42

      "

       "

       

      Let me be the first to say that it was foolish to use an air admittance valve in new construction."

       

      I was reading all the posts and started cracking up when I read yours!

      Its funny because that went thru my mind when I read the op but as soon as i started reading more, that thought went away.

  4. User avater
    Matt | Feb 06, 2009 04:16pm | #15

    I think you have some good info above but on a related note be aware that sometimes new septic systems smell extra bad until the system gets going.  This would be outside the house though (if all the plumbing is working properly).  Like sewer gas comming out the vents in the roof.  I don't know - maybe it would help if you put some of that septic tank additive down the toilet.  When we built this house - it probably took 9 months before we stopped smelling it out in the yard.  Maybe this might have contributed to your problem.

  5. user-201496 | Feb 06, 2009 05:06pm | #19

    I would call the plumber and the city plumbing inspector and have them meet to try to find the problem.

    1. barmil | Feb 07, 2009 05:03am | #33

      The city inspector will likely decide that you have to tear out all of the walls to fix the problem, and the plumber will deny any liability. Not my choice.

      1. barmil | Feb 07, 2009 05:20am | #34

        Talking to myself.

         I consider AAVs to be viable in an older home with no other options, but new construction isn't what I'd consider a good idea for it. Since homes don't usually come with owners manuals, and most new home buyers may not be very knowing about plumbing (they grew up assuming it always works, thanks to their dads), they shouldn't have to deal with an AAV. Yeah, cheap, irresponsible work, in my mind. I like the fart analogy. If the smell doesn't go away quickly, there's another problem. I have to pour water into my basement floor drain from time to time, for instance, since the heater/AC no longer drain into it to maintain the trap's water.

        Since this is in the kitchen sink, do you have a disposer (I'm sure that you do)? What are the chances that waste got into the AAV and kept it from closing? Not the same for one on a bathroom sink drain. I've had waste briefly come up into the second sink bowl when using my disposer, so I can picture the same for the AAV. Just a thought.

      2. user-201496 | Feb 07, 2009 07:50pm | #39

        Their not going to make you tear out any walls. But they probably will hold the plumber's feet to the fire to fix the problem.

        1. DanH | Feb 07, 2009 08:25pm | #40

          Maybe it's the plumber's feet that stink in the first place.
          The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith

  6. wallyo | Feb 06, 2009 07:40pm | #23

    Sure that during construction something did not crawl into the duct and has gone to Jesus.
    Had something similar happen with an apartment I rented I had an smell in the living room corner, could not figure it out moved the couch cleaned etc. Still had a smell, turns out a cat got into the crawl space (less then code 1920 building) and pasted away. It got in through a unscreened foundation vent. In other words the air vent may of not had anything to do with the order.

    We once were watching my wife's cousin's cat, I was replacing the filters on the furnace it a down draft filters are on top 6 feet up, went into the the house for something. Finished up, later that night or the next day we noticed the cat was gone ( we don't like cats too much hence the lapse in noticing). For three days we could not find the thing. Then at 2:00 in the morning we hear a Low Meow. Open the bedroom door to the deck, no cat, go to the front door, no cat. Just a real low long Meow.

    After twenty minutes we figure out it is in the cold air return.

    Also had a squirrel run into the garage once while being chased by another squirrel.

    Wallyo

  7. mike_maines | Feb 06, 2009 08:26pm | #24

    Check that the washing machine hose isn't pushed too far down into the drain.  It can siphon the trap dry and let the stink in. 

  8. Norman | Feb 06, 2009 08:28pm | #25

    The nasty part of sewer gas is methane based, so a bunch of candles thru out the house or a fire (if you have a fireplace) may help burn off the methane.

    Or rent an ozone generator.

    Both of these solutions presume that the source of the gas has been dealt with and you are just dealing with the residual.

    Good luck.

     

  9. Pelipeth | Feb 06, 2009 09:32pm | #27

    You can get a product called Odors Away, local hardware store should carry it. Place on ceramic dish and inside the duct work. Clears things up like a miracle. Can't find it call 800-621-6947.

  10. rdesigns | Feb 27, 2009 06:00pm | #56

    Nasty odors are one of the hardest things to fix. Finding the source is, of course, the answer. Here are a few low-tech tips to help you locate it.

    The air circulation of the duct system will spread odors from any source, so don't be too quick to conclude that it is the actual source. To test, shut off the furnace blower for a few minutes, go to to the return air opening nearest the furnace and sniff. Do this with all the supply registers and return grilles. If the odor is definitely stronger at one of them, remove the register or grille and lay a powerful flashlight in the branch duct to shine back along the duct while you use a small mirror to inspect.

    I have seen new houses that had a nest of dead starlings in the vent for the bath exhaust. They got in there when the exhaust duct was hanging out of the soffit without a screen during construction. They died in there after being trapped when the duct was finished. Test for this by running the exhaust fan and sniffing at the outlet.

    To check the entire plumbing system for vent leaks, go to the drug store and buy a small, cheap bottle of peppermint oil (camphor oil is also good for this test.) Open the lowest cleanout plug in the drain system and carefully, without spilling any except in the pipe itself, dump the whole bottle into the drain and replace the plug. Close all windows and doors. Now, having made sure no one in the house uses the plumbing during your test, de-pressurize the entire house by simply turning on all exhaust fans (including the dryer, since it will exhaust about 200 CFM, by itself.) Any leaks in the plumbing vents will give off the distinctive peppermint odor. This test will also reveal any faulty AAV's since they are designed to close against leaks from inside the piping.

     

    1. cussnu2 | Feb 27, 2009 09:16pm | #57

      Based on what i have seen on here in other threads, I would go outside and look to see if your vent stack/stacks are even vented.  In other words, do you see them coming out of the roof.  Assuming you see pipes coming out of the roof, I would check in the attic to see if those pipes on the roof are actually connected to anything.

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    • A Kominka Comes West
    • Making Small Kitchens Work

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