We have a 24 year old home 10 minutes out of Winnipeg, Manitoba. We have done some renovations … new concrete floor in the basement along with new plumbing, now gas furnace, gas hot water tank. Since these renovations we have noticed, expecially in the winter months, a strong sewer smell. Thus far we have taken the rod out of the hot water tank, have had a contractor dig up our back yard just to tell us that the line from the septic tank to the house was totally in tack! We have poured boiling water down the vent in the winter, just in case it was frozen. We shock our well at least twice yearly.
The smell seems to eminate from the fresh air vent and it is very very strong in the winter when someone is taking a long hot shower or a hot load of laundry.
I would appreciate any possible leads you may have. Winter is coming and I do not want to deal with this odor for another year.