I have a client with a W/D (Maytag Neptune) in their kitchen – has worked fine for 10 years (except when Maytag has seal problems/mildew smell – fixed).
Just this fall/winter, if she does 3-4 loads of laundry in succession, it appears that she loses the trap seal in the washer standpipe and gets sewer gas back into the kitchen and an adjacent room – not a pretty smell.
If she pours water into the standpipe and doesn’t use the washer it goes away.
If she comes back and does a few loads the smell comes back.
The standpipe is close to where the house sewer exits the foundation wall. The standpipe has been augered by a pro for at lease 25′ or so downstream. A plumber has cut open a closet wall and sees that there doesn’t appear to be any leaking from the standpipe trap, although the trap seems a bit shallow.
The washer pump was replaced recently because it was 9 years old and seemed a little sluggish.
Ideas?
Jeff
Replies
Have you checked the vent? if it's siphoning the trap it may be that there is not enough air getting into the vent to prevent siphoning.
Climb up on the roof and run a garden hose down the vent and have someone crank it up to full flow. If the water gushes up out of the vent and covers the roof with a thin sheet of wet ice you will have found your problem.
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"You cannot work hard enough to make up for a sloppy estimate."
10:52 for both replies ;-)
"Why do you hurt me when I do bad things to you?" My youngest son to his older brother
Must be the witching hour. New NC code just went back to at least one 3" vent through the roof and we now need to up-size from 2" to 3" when a vertical laundry box line goes to horizontal. I assume that some of the high speed pumps on the new laundry machines were backing up at the bottom of the stack. I never heard of it happening but I suppose it could be the problem with this situation. ------------------
"You cannot work hard enough to make up for a sloppy estimate."
It's a "sudsing" issue.
On my highrises we have to parallel the horizontal pipe at least 8' before we can tie in a suds producing stack.
Most think it's not a big deal until they see a tub on the first floor oozing foam from the drain.
"Why do you hurt me when I do bad things to you?" My youngest son to his older brother
Very Interesting. Thanks for the clarification. There making this part of the regular residential code here in NC. Does this make sense to you? I really don't need the plumbing code to make sense, just tell me the rules and I'll do my best not to screw it up, but I do find it fascinating... like dungeons and dragons in 3-D or the secret life of pipes.------------------
"You cannot work hard enough to make up for a sloppy estimate."
I'ts code here for residential & commercial, it is a height generated code though.
As you noted newer washers that cycle faster also dump water faster, a larger pipe can handle more suds without it trying to force it's way out of a trap.
"Why do you hurt me when I do bad things to you?" My youngest son to his older brother
The stand pipe needs to be 18 to 30" long.
The trap needs to have 2" of trap seal minimum---- that is 2" from the weir of the trap to the bottom of the trap arm.
The trap arm needs to be less than 5' in total length---- that is 5' from the trap to the vent take off.
All of this pipe needs to be 2" minimum.
If all those conditions are met there are a couple of things that could be failing.
1. plugged vent.
2. Discharge hose from washing machine has too tight of a seal to the stand pipe ( that's rare & usually not a problem)
Thanks for the responses - I believe all of those 'conditions' are met but I'll have someone double-check - remember it's been just fine for ten years.
If the water gushes up out of the vent and covers the roof with a thin sheet of wet ice you will have found your problem.
And, you have a very quick way down off the roof ;o) right?
Don't think it's a plugged vent but we'll see.
Suds issue ... hmmmm on that one - can you tell me more?Jeff
Edited 1/5/2008 1:34 am ET by Jeff_Clarke
The suds issue on my jobs is suds producing stacks that have tubs, showers, & clothes washers on them that are more than 4 stories. When they go from vertical to horizontal at the bottom they need to have atleast an 8' run parallel to the drain if that drain has any fixtures connected to it on that floor.
It's a big factore on 5 to 50 story highrise residential buildings.
As the changed the code in NC to a larger pipe to help leviate sud pressure from trying to backfeed through another fixtures trap on that same level.
"Why do you hurt me when I do bad things to you?" My youngest son to his older brother
Got it - thanks!
Jeff
Does the type of detergent or how much they are using add to the problem? I've heard that detergents are supposed to formulated not to suds up to much.
The new front load washers have instructions to use a certain type of detergent formulated just for them.
Well if you use a standard soap, more suds equals more problems.
When I was a starving student & didn't have laundry detergent, I used regular dish soap------- that was cool lookin.
Looked like one of those foam party at the nightclubs at spring break.
"Why do you hurt me when I do bad things to you?" My youngest son to his older brother
Apparantly there is a special HE detergent sold by sporting goods stores for removing odors from athletic clothing that has the side effect of removing oder from the rubber gasket on front loading washers. Might be worth a try. We just run a load of towels with bleach once every week or two and that solves the gasket odor at our house. Sounds like you have a true sewer gas problem and that will be a trap siphoning issue. Figure out why the trap is siphoning and you'll solve your problem.Maybe cut into vent behind the washer and "Y-in" a studor vent in addition to the roof vent?------------------
"You cannot work hard enough to make up for a sloppy estimate."
I can't help with the fix, but I can cure second the problem! I had that same Neptune and the same sewer smell coming from it. I never did check the vent. The Maytag repairman who came to replace the seal and wax motor (class action suit) said everything looks and smells normal to me, so did the plumber I called to look at it.
It smelled like the inside of a toilet in the laundry room for days on end, never did get a fix. I have since moved--the washer forced me out of the house (kidding, but it did keep me from doing more laundry than necessary, which may be a bessing in disguise).
For front load washers, manufacturers reccomend that the door be left open between uses to allow the washer to dry out. Residue gets built up on the rubber boot and feeds mildew, so it must be kept clean. Poor material choice/ design IMO. Found it helps to dump some white vinegar in with each load. Seems to help it stay cleaner and doesn't leave any odor in the laundry either.
Thanks - I'm not talking about the seal problem with the Neptune that produced a mildew smell - this was widely known and was fixed as a problem a while back.
This is a real sewer gas problem.
I'll ask about the detergent.
Jeff
I also have the same problem, so I'll be waiting to see what your fix is. Mine is do less laundry, With the kids gone its an easy solution. We snaked from the roof down, no luck. Someone said to add a conection at the washer, an air valve release ? Went to Ace to buy one and their plumbing fella sold us a snake,instead of the valve I asked for .Anybody got some more info on the valve , and where to connect it? Thanks
Maybe the Plumber did not know how to vent correctly. Most of the repair Plumber here in SoCal never went to Plumbing School.
The one on the left is the wrong way to do it.
The standpipe termination is part of the in-wall plastic hose bibb box, so I don't think that's it.
Interestingly, if she pours water into the trap from above, the sewer gas stops for a bit then returns. To me, this seems like either (a) a leaky trap (but we can see it and it does not appear to be leaky) or (b) trap siphoning (which under the circumstances above seems a bit unlikely.
Jeff
I forgot to mention that besides the sewer gas, the toilet water closest to the washer actually purculates !
This is too simple and probably something that's already been checked but I'll mention it anyway just in case. I just had a new washer installed. The installer shoved the entire length of the washer's drain hose down into the drain pipe until it bottomed out in the trap. A few loads of laundry later we were getting sewer gas in the room. I cut about 2' off the hose and all is well.
Nice try ... but the same hose went back in. Plus, see post above re: leak?
Jeff
Jeff,
I agree with Bob. Check the lenght of the discharge hose. I bet it too long and goes right past the trap. I had the same problem at my house with a new front loader. I pulled out the hose a bit and the problem went away.
Good luck.
Michael
What really happened:This actually wasn't a sewer gas OR washer OR vent problem at all.
What happened is that the dryer exhaust connection slipped off the through-wall vent sleeve and the dryer was exhausting into the wall cavity and an adjacent crawl space.
The odor was a combination of the ethanethiol / mercaptans added to NG plus some amount of mildew in the wall.
Jeff