Ask Your Question

Angie's List Answers is the trusted spot to ask home improvement and health questions and get answers from service companies, health providers and consumers. For ratings and reviews on companies in your area, search Angie's List.

 
 
or
Submit
Top 30 Days Experts
Rank Leader Points*
1 kstreett 240
2 Guest_9020487 110
3 Guest_9190926 105
4 GoldenKid 100
5 ahowell 95
6 KnowledgeBase 95
7 skbloom 80
8 Guest_98024861 70
9 Guest_9311297 70
10 Guest_9400529 70

*Updates every 4 hours

Browse Projects By Category

Question DetailsAsked on 10/7/2016

My floor drain in basement has a sewer gas smell coming from it. Washing machine drains to it only.

When the washing machine isn't draining to the floor drain there is a sewer gas smell coming from it. I tried pouring bleach and vinegar down the hole and it did not stop the smell. The drain does not back up with water but there is always standing water in the drain.

Do you have the same question? Follow this Question


4 Answers

Voted Best Answer
1
Vote

Hi,

This is Robin in Member Care. Thanks for your interest in Angie's List!

We'll be happy to help find top rated appliance repair services, but it doesn't look like you have a subscription to the List yet. You can join by visiting www.angieslist.com or by giving us a call at (888) 944-5478. Our call center is available 8:00 am-9:00 pm weekdays and 8:00-5:00 pm ET on Saturdays.

Thanks for your question and we look forward to assisting you!

Answered 2 years ago by Member Services

0
Votes

If always standing water in drain and there is sewer gas coming out, one of two likely causes:


1) this is a drain with a side snaking port - a type that has a trap in the bottom but also has a side access for a sewer snake to bypass the trap - some types (older ones that I have seen mostly) have a flapper on the side port that, if it gets jammed open with gunk, can let gas into the house. Drain fitting looks like this - several different configurations out there but all have a side route and a trap both - there are also some types that use a float ball to stop gas entry and backflow, and if the ball sticks it can cause issues -


https://www.askmehelpdesk.com/plumbin...


Other alternative - if gas comes out only when water is being run in the house, could be that water is partially plugged up somewhere downstream, so it is backing up in the pipes. The air (sewer gases) that are in the line have to go somewhere as that water fills the sewer line, so it will take the easiest exit. If this backup is underground (under slab say) almost always that is downstream of where the sewer vent to the roof is, so if the line is full of water or if the water in the trap is low, the gas bubbles up through the water in the floor drain trap or other lowest elevation drain. Obviously, if the trap water is low because of evaporation it comes out there easier than up through the water to the vent - so keeping the floor drain trap full of water (I add some lemon scented Mr Clean to mine to keep from going stagnant smelling) reduces the chance of this happening - topping it off with water every 3-6 months typically (more in very dry house conditions), and pouring a gallon of water with Mr Clean down it every 2 years on a calendar schedule to totally flush it out.


If the sewer line is backing up, even with the roof vent it is very common for floor drains to back up (gas first, then eventually liquids coming out as the partial blockage in the sewer line becomes more complete) and gurgle through the water in the trap - starting when large water loads are passing through. Washing machine causes it first usually, then full tub emptying, then toilet flushing though usually by that time washer or tub emptying is causing overflow at the drain.


First thing I would do - if you only put a bit of bleach and vinegar down there it might not have filled up the trap, so I would flush out the drain with a full gallon of water - both to remove the bleach and vinegar (which could damage the drain sitting in it indefinitely) and to ensure the drain was flushed of any stagnant water - could be the trap water either went totally stagnant (swampy smell) or went dry enough some sewage backed up into it to fill it and that is what you are smelling.


Then, when running washing machine (unless it dumps straight into the floor drain which would conceal the gurgling) or otherwise emptying a tub that is about half full of water (not full, not trusting your floor strength to hold a full tub of water), listen at the floor drain to hear if it is gurgling gas. If so, likely you need your sewer line cleaned out - I prefer full diameter mechanical routing unless clay tile or deteriorated cast iron or any type of fiber pipe which full-daimeter scraping might damage, jetting is OK but misses a lot of spots commonly so needs an on-board camera to be able to look at the pipe as it is pulled back out after the jetting run to be sure it is fully cleaned out to full diameter everywhere. Sewer and Drain Cleaning is your normal Search the List category for that type of cleaning - and it should be cleaned all the way to the street even if a clog is found part way along, because routing out a clog and stopping there just risks the clog sticking further down the line. Plus sewer lines should be cleaned every 10-20 years typically just to restore the full diameter, because soap scum and fiber and grease sticks to the inside and reduces the diameter until noticeable clogging occurs.


If not gurgling when a lot of water is running, but gas smell is still occurring then I would call a Plumber - possible the drain fitting is cracked and letting gas up around it or something like that.


BTW - draining washing machine directly to floor drain, especially if the drain hose is stuck down into the drain, if that is what is happening, is not legal - should be going into a standpipe drain leading into the sewer stack with a proper trap. Washing machine discharge can plug up the drain trap with lint fairly quickly. Or in some areas discharging to a laundry washtub is legal.


One other thought on that - if the washer drain hose is stuck down into the trap, it is possible that the discharge is flushing out the trap during discharge due to the water flow from the washer, but not refilling the trap - hence letting sewer gas in.


BTW - here are links to a couple of previous similar questions with answers FYI -


http://answers.angieslist.com/the-dra...


http://answers.angieslist.com/how-unc...




http://answers.angieslist.com/Basemen...

Answered 2 years ago by LCD

0
Votes

Robin from Member Care indicated you need an Appliance Repair specialist - actually, Sewer and Drain Cleaning or Plumbing would be the categories you might need, depending on whether you are getting gas blowback because of a partial blockage downstream causing gas ejection when other water is flowing downthe drain lines, or Plumbing if the problem is believed to be in the drain/trap itself.

Best of both worlds would be to find a Plumber who also does full-line sewer cleaning (able to reach clear to the street) and is able to bring that equipment and camera in case it is needed instead of plumbing, or if camera is needed to evaluate the problem.

Other alternative, if your sewer lines have not been cleaned in a decade or more or have a history of backing up from root intrusion or such, is have a sewer cleaning contractor rout out the line and see if that solves the problem, knowing it was likely to be needed soon anyway even if it does not solve the problem. Certainly an easier initial approach (taking a 1 out of 2 chance) than tearing into the floor to replace the floor drain/trap on the assumption that is where the problem is.

Answered 2 years ago by LCD

0
Votes

OK - my second entry got clipped - ignore the 3-paragraph version above and read this one -


Robin from Member Care indicated you need an Appliance Repair specialist - actually, Sewer and Drain Cleaning or Plumbing would be the categories you might need, depending on whether you are getting gas blowback because of a partial blockage downstream causing gas ejection when other water is flowing down the drain lines, or Plumbing if the problem is believed to be in the drain/trap itself. The appliance itself is not the source of the problem other than if it is causing the trap to siphon out as described below the ====, below. Best of both worlds, since you don't know exactly which you need, would be to find a Plumber who also does full-line sewer cleaning (able to reach clear to the street) and is able to bring that equipment and camera in case it is needed instead of plumbing, or if camera is needed to evaluate the problem. My first check would be to fill the trap (use a gallon or so of water to flush it out too) and see if that stops the problem between washer uses - could be the washer is just siphoning the trap water out when it empties, in which case the permanent solution would be to properly plumb the washer discharge. Another approach, if your sewer lines have not been cleaned in a decade or more or have a history of backing up or have root intrusion history or such, is have a sewer cleaning contractor rout out the line full-diameter (not just snake) and see if that solves the problem, knowing that was likely to be needed fairly soon anyway even if it does not end up solving the problem. Certainly a cheaper and easier initial approach (taking a 1 out of 2 chance) than tearing into the floor to replace the floor drain/trap on the assumption that is where the problem is.=====One other possible cause I did not address but might be the cause - and either contractor type can check this out. You said the drain always has water in it - but like a toilet bowl, unless the water covers the TOP of the trap (the top of the outlet hole from the toilet bowl or the top of the pipe in the bottom U-bend in the drain trap) gas can get in. Actually, because of wind surges and siphon effect when draining and sewer gas pressure in the system a trap may need more than just enough water to fully seal the very bottom of the trap - the reason the U part is 6 or more inches "high". So - here is the scenario. If your sewer vent line to the roof is plugged then there is not an "upstream" source of replacement air, so when water flows down the sewer line it can create a partial vacuum, or "siphon" water out of traps and pull air from the inside of the house. When it does this it pulls the water out of the trap until it breaks the water seal and air comes in (like holding a bottle filled with water upside down - it gurgles as air comes in to replace the liquid that is leaving) - causing a gurgling sound like you have probably seen/heard in toilet at times when flushing, before it refills the bowl. The toilet avoids this trap air-gap problem by trickling more water into the bowl after the flush, to refill the bottom of the bowl and reestablish the water-filled "trap" by submerging the outlet opening of from the bowl - thereby preventing sewer gas intrusion. In a floor drain there is no source for this refill water, so it might pull the water down enough in the trap to expose an air gap in the trap or not have enough waer depth to counteract the low sewer gas pressure attmepting to get in - perhaps leaving some water sitting in the bottom of the U but not enough to seal off the movement of sewer gases, which would gurgle as they come into the drain - usually at least initially (until trap goes near dry) when water is flowing down the sewer line from some other source. Same situation as previously mentioned if the washing machine discharge hose is jammed into or drains directly into the trap - where the flow could cause the water in the trap to flush or siphon out and leave the bottom of the trap with a bit of water but not enough to provide a water seal. Also - if the water depth in the trap is low, the air being pushed ahead of significant water flow coming down the sewer line can also pressure up the line a bit and cause trap sewer gas release - especially if your sewer line has a low spot that acts as a downstream "trap" so the air being pushed down the line can't just go directly to the street sewer line. One other remote possibility, since the washer is dumping into the floor drain (another reason not to do this) is there is a lot of fibers in washer discharge water (whether or not your washer has a lint trap tray), and these can line the trap and cause it to wick the trap water down the drain - so even of the drain trap is full of water after the washer is done pumping out the water from a load, the fibers can wick the trap down to the point where it will let sewer gas in - sometimes in just hours or a day or two. To check if siphoning during discharge or wicking is the issue, measure how far below floor level the water is normally - then fill the drain up with water slowly and once the level has stabilized, measure again - if not essentially the same, then the trap is not fully refilling after the washer discharge is done or is leaking or wicking out. Measure several times after washer use to get an average reading. Also check if it the level drops significantly (ignoring windy days when vent stack vacuum can lower the level) between wash days, or if it drops when tub is emptied or toilet is flushed or such - which could indicate a leak in the trap or blocked vent stack. If it gurgles when emptying bathtub or flushing, as indicates before, you likely have a partial downstream sewer line blockage and routing it out would be my first approach. Bad news on the washer discharge - moving it from the existing floor drain discharge. In a basement it probably means cutting concrete to make a direct connection with a proper washer standpipe drain to the sewer "stack" or sewer line unless the "stack" - the above-ground sewer lines in the house - happens to be nearby and can be cut into near floor level. An above-slab cut-in and washer drain connection can run in the $300-500 range commonly depending on accessibility of the stack - cutting through the slab to tie into the line there (including repair) commonly at least $500 and in the $500-1000 range commonly, though can be more in cases where it is hard to access the sewer line, with clay or fiber or asbestos sewer pipe, thicker than usual slab, groundwater close up under the slab that needs pumping out to work, interfering underslab drain pipes, very high labor rate area, or other complicating situation. Another sort of hokey solution but one that is legal and is used at times (more commonly with water heaters and boilers that have an emergency overtemp/ overpressure valve connected to a sewer line, or with sump pumps that tend to go nearly dry and stagnant in certain seasons) - if it turns out that the washer discharge is flushing out the trap water and leaving an air gap for sewer gas entry, is installing a trickle line to the drain - a tubing from a tap on a water line (be sure is has a good ball valve on it) leading to the floor drain which trickles water into it constantly - just enough to keep the trap filled, maybe a gallon or two per hour. Of course, in a very high water cost area this might not be desireable - or it could be plumbed with an electric valve that works off the washing machine cord so it only flows when the washer is drawing power. This type of electric valve is usually used to shut off the water lines when the washer is not in use to minimize the risk of flooding from a hose failure, but could be rigged to provide a trickle feed as well. Plumber could do this for typically a couple to three hundred - maybe less if done while he is there diagnosing the problem.

Answered 2 years ago by LCD

0
Votes

OK - first it clips the response, then it deletes all paragraph breaks and downsizes the font - I will try to clean it up for you here and at least see if I can get the paragraph breaks back in so it is readable:


OK - my second entry got clipped - ignore the 3-paragraph version above and read this one -

Robin from Member Care indicated you need an Appliance Repair specialist - actually, Sewer and Drain Cleaning or Plumbing would be the categories you might need, depending on whether you are getting gas blowback because of a partial blockage downstream causing gas ejection when other water is flowing down the drain lines, or Plumbing if the problem is believed to be in the drain/trap itself. The appliance itself is not the source of the problem other than if it is causing the trap to siphon out as described below the ====, below.


Best of both worlds, since you don't know exactly which you need, would be to find a Plumber who also does full-line sewer cleaning (able to reach clear to the street) and is able to bring that equipment and camera in case it is needed instead of plumbing, or if camera is needed to evaluate the problem.


My first check would be to fill the trap (use a gallon or so of water to flush it out too) and see if that stops the problem between washer uses - could be the washer is just siphoning the trap water out when it empties, in which case the permanent solution would be to properly plumb the washer discharge.


Another approach, if your sewer lines have not been cleaned in a decade or more or have a history of backing up or have root intrusion history or such, is have a sewer cleaning contractor rout out the line full-diameter (not just snake) and see if that solves the problem, knowing that was likely to be needed fairly soon anyway even if it does not end up solving the problem. Certainly a cheaper and easier initial approach (taking a 1 out of 2 chance) than tearing into the floor to replace the floor drain/trap on the assumption that is where the problem is.


=====


One other possible cause I did not address but might be the cause - and either contractor type can check this out. You said the drain always has water in it - but like a toilet bowl, unless the water covers the TOP of the trap (the top of the outlet hole from the toilet bowl or the top of the pipe in the bottom U-bend in the drain trap) gas can get in. Actually, because of wind surges and siphon effect when draining and sewer gas pressure in the system a trap may need more than just enough water to fully seal the very bottom of the trap - the reason the U part is 6 or more inches "high".


So - here is the scenario. If your sewer vent line to the roof is plugged then there is not an "upstream" source of replacement air, so when water flows down the sewer line it can create a partial vacuum, or "siphon" water out of traps and pull air from the inside of the house. When it does this it pulls the water out of the trap until it breaks the water seal and air comes in (like holding a bottle filled with water upside down - it gurgles as air comes in to replace the liquid that is leaving) - causing a gurgling sound like you have probably seen/heard in toilet at times when flushing, before it refills the bowl. The toilet avoids this trap air-gap problem by trickling more water into the bowl after the flush, to refill the bottom of the bowl and reestablish the water-filled "trap" by submerging the outlet opening of from the bowl - thereby preventing sewer gas intrusion. In a floor drain there is no source for this refill water, so it might pull the water down enough in the trap to expose an air gap in the trap or not have enough waer depth to counteract the low sewer gas pressure attempting to get in - perhaps leaving some water sitting in the bottom of the U but not enough to seal off the movement of sewer gases, which would gurgle as they come into the drain - usually at least initially (until trap goes near dry) when water is flowing down the sewer line from some other source. Same situation as previously mentioned if the washing machine discharge hose is jammed into or drains directly into the trap - where the flow could cause the water in the trap to flush or siphon out and leave the bottom of the trap with a bit of water but not enough to provide a water seal.


Also - if the water depth in the trap is low, the air being pushed ahead of significant water flow coming down the sewer line can also pressure up the line a bit and cause trap sewer gas release - especially if your sewer line has a low spot that acts as a downstream "trap" so the air being pushed down the line can't just go directly to the street sewer line.


One other remote possibility, since the washer is dumping into the floor drain (another reason not to do this) is there is a lot of fibers in washer discharge water (whether or not your washer has a lint trap tray), and these can line the trap and reach from the trap to the sewer line past the trap, and cause it to wick the trap water down the drain - so even if the drain trap is full of water after the washer is done pumping out the water from a load, the fibers can wick the trap down to the point where it will let sewer gas in - sometimes in just hours or a day or two. To check if siphoning during discharge or wicking is the issue, measure how far below floor level the water is normally - then fill the drain up with water slowly and once the level has stabilized, measure again - if not essentially the same, then the trap is not fully refilling after the washer discharge is done or is leaking or wicking out. Measure several times after washer use to get an average reading. Also check if it the level drops significantly (ignoring windy days when vent stack vacuum can lower the level) between wash days, or if it drops when tub is emptied or toilet is flushed or such - which could indicate a leak in the trap or blocked vent stack. If it gurgles when emptying bathtub or flushing, as indicated before, you likely have a partial downstream sewer line blockage and routing it out would be my first approach.


Bad news on the washer discharge - moving it from the existing floor drain discharge. In a basement it probably means cutting concrete to make a direct connection with a proper washer standpipe drain to the sewer "stack" or sewer line unless the "stack" - the above-ground sewer lines in the house - happens to be nearby and can be cut into near floor level. An above-slab cut-in and washer drain connection can run in the $300-500 range commonly depending on accessibility of the stack - cutting through the slab to tie into the line there (including repair) commonly at least $500 and in the $500-1000 range commonly, though can be more in cases where it is hard to access the sewer line, with clay or fiber or asbestos sewer pipe, thicker than usual slab, groundwater close up under the slab that needs pumping out to work, interfering underslab drain pipes, very high labor rate area, or other complicating situation.


Another sort of hokey solution but one that is legal and is used at times (more commonly with water heaters and boilers that have an emergency overtemp/ overpressure valve connected to a sewer line, or with sump pumps that tend to go nearly dry and stagnant in certain seasons) - if it turns out that the washer discharge is flushing out the trap water and leaving an air gap for sewer gas entry, is installing a trickle line to the drain - a tubing from a tap on a water line (be sure is has a good ball valve on it) leading to the floor drain which trickles water into it constantly - just enough to keep the trap filled, maybe a gallon or two per hour. Of course, in a very high water cost area this might not be desireable - or it could be plumbed with an electric valve that works off the washing machine cord so it only flows when the washer is drawing power. This type of electric valve is usually used to shut off the water lines when the washer is not in use to minimize the risk of flooding from a hose failure, but could be rigged to provide a trickle feed as well. Plumber could do this for typically a couple to three hundred - maybe less if done while he is there diagnosing the problem.

Answered 2 years ago by LCD




Related Questions


Terms Of Use
|
Privacy Policy