Sewer Gas Smell


  #1  
Old 01-23-23, 12:16 PM
S
Member
Thread Starter
Join Date: Jan 2014
Location: usa
Posts: 40
Upvotes: 0
Received 0 Upvotes on 0 Posts
Sewer Gas Smell

I have a ranch home on a well/septic. When I run my washer (main floor), the basement gets a STRONG smell of sewer gas. The washer is on the furthest end of the house, away from the septic tank - so the water has a long run to get to the septic (3800 SF home). I do have a drain, toilet, shower and sink in the basement, ran water into all of them, so no dry traps. This only happens when we use the washer. It may also happen when we use the bathroom next to the washer, but that bathroom is seldom used so we may not notice if it did happen. The smell doesn't occur when using the shower closest to the septic tank. There are no leaks in the waste pipe. I would think if I had a cracked waste or vent pipe, I would have the smell all the time. Any ideas what this could be? Would a blocked vent pipe cause this to happen. Lived in the house for 20+ years, recently started happening about 6 months ago.

Thanks - Adam
 
  #2  
Old 01-23-23, 04:03 PM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 28,592
Received 1,708 Upvotes on 1,525 Posts
Is the basement unfinished?
Are the majority of drain pipes in the basement ceiling or are they buried under concrete?

If you have access to the piping I'd spend some time inspecting for anything cracked or broken. Other than that I'd be ready for the next load of laundry. Be down in the basement before washing clothes and before the smell appears. Then start a load of wash and stick your head up into the space (basement ceiling) under the washer. Run your hand around every drain pipe fitting feeling for anything wet. And, keep your nose active for a clue as to the source of smell.

Is the downstairs bath in the smell area? If so is the smell stronger near the base of the toilet?
 
  #3  
Old 01-24-23, 08:38 AM
S
Member
Thread Starter
Join Date: Jan 2014
Location: usa
Posts: 40
Upvotes: 0
Received 0 Upvotes on 0 Posts
The basement is finished with all the drain pipes in the ceiling. The waste pipe was replaced about 10 years ago - went from cast iron to pvc, so I am fairly certain the waste pipe is fine. Can't say the same about all the drain pipes going to the waste pipe.

Next time we do laundry, I will go in the basement to see if I can find out where the smell is originating.

Thanks.
 
  #4  
Old 01-24-23, 09:26 AM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 28,592
Received 1,708 Upvotes on 1,525 Posts
There are a lot of inexpensive endoscope camera options. Their camera can be sent through small holes and cracks in the ceiling & floor (gaps around registers, gaps around ceiling light fixtures, or through holes drilled in the ceiling...) to look for potential leaks.

A IR thermal camera (FLIR) could also be useful if there is water leaking somewhere. The water evaporates and gets cold making it easy to spot in infra red.
 
  #5  
Old 01-24-23, 11:00 AM
Z
Forum Topic Moderator
Join Date: Sep 2005
Location: USA
Posts: 6,406
Received 357 Upvotes on 319 Posts
I do have a drain, toilet, shower and sink in the basement, ran water into all of them, so no dry traps.
I wonder if the venting is substandard or blocked, causing one or more of the traps to be sucked dry when the washer empties.

Do you hear any gurgling in any of the basement traps when the washer drains?
 
  #6  
Old 01-24-23, 11:09 AM
S
Member
Thread Starter
Join Date: Jan 2014
Location: usa
Posts: 40
Upvotes: 0
Received 0 Upvotes on 0 Posts
The basement drains empty into a basin and then when it fills, there is an ejector pump that pumps it up into the septic tank. I don't believe the drains in the main floor would have any affect on the drains in the basement - but I really don't know.

The strange thing is, the smell is in the basement, not on the main floor (the smell does permeate up when it gets really bad).
 
  #7  
Old 01-24-23, 12:42 PM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 28,592
Received 1,708 Upvotes on 1,525 Posts
Definitely look at the ejector pit as they can be a bit prone to smells. There is a big lid and penetrations for the pipes that must be sealed gas tight and they can leak over time as gaskets harden and crack with age. Also look at the vent for the sump as it's really important to let air in and out of the chamber so it doesn't force past the seals. They also send the waste out under pressure which can make leaks more prone than with a gravity drain line.
 
  #8  
Old 01-24-23, 12:50 PM
S
Member
Thread Starter
Join Date: Jan 2014
Location: usa
Posts: 40
Upvotes: 0
Received 0 Upvotes on 0 Posts
If it was the ejector pit , wouldn't it have a smell all the time? The smell only happens when using the upstairs laundry drain (which drains into the utility sink). The drains from upstairs go directly into the septic tank, it does not go into the ejector pit first.
 
  #9  
Old 01-27-23, 06:14 AM
A
Member
Join Date: Mar 2010
Location: USA
Posts: 5,005
Upvotes: 0
Received 245 Upvotes on 225 Posts
To help narrow down on the problem, try this, Fill several buckets totalling a little over ten gallons of water. Without using the washing machine for several hours, quickly empty all the water into the laundry sink (without overflowing). Do you get the sewer gas smell?

Several hours before or after doing the preceding get a few buckets filled with water and sitting in the basement. Start the washing machine. After enough water drains from the waching machine to rise in the laundry sink as high as it normally does, quickly go around to all the (basement only) drains and toilets including the floor drain and dump about a quart of water into each. When the washer stops dumping into the laundry sink dump another quart into each other drain. Do you get the smell? (Stop the machine before the rinse part of the cycle and finish your judgment about the sewer smell, then have the machine finish the rest of the cycle.) .

I do think that clogging of the plumbing vents is part of the problem or all of the problem. Someone will have to go up on the roof in most cases to diagnose and fix that problem.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: