Posted 12/23/2018 10:41 (#7191068 - in reply to #7188669) Subject: RE: Washing Machine Stinks Up The House
just a tish NE of central ND
I agree. That trap below the septic line instead of well above the bottom line is the problem. Every time you flush a toilet it puts pressure in the p trap and adds sewage to the P trap. That presure of the downflow it lifting the sewage in the p trap up into the stand pipe / mixing with its water/ and then dropping back down to its level when it drains way in the black cast ...smell is venting.The p trap might even be emptying out from the surge.
Also check the cast pipe for holes rusted through on the top side of pipe....... sewer gas has been known to erode holes in the cast pipes.there are a LOT of cast and steel pipes still used in older farm homes here from decades ago...