We live in a hi-ranch. In the basement we have a bathroom with a shower stall. Every winter since we moved in(4 years) when it gets cold ie: over minus 10 there is a sewer smell coming from that bathroom. The sewage holding tank is in the bathroom closet. This services all plumbing in the basement,it is then pumped up to the septic tank. Also in this closet is a ventilation system with 2 vents coming in from the outside. We have changed the seal on the toilet in that bathroom but it did not correct the problem. I believe the smell is coming from the tank. Any suggestions to how to repair this problem
Answer:
You may be having a bit of a problem with the plumbing stack on the roof. Sewer gas return can be caused by the top of that stack not permitting gasses to escape fast enough and of course, the gasses build up and escape wherever they can - probably somewhere along the seal that is supposed to hold the holding tank cap in place.
