We have recently had a new septic tank put in our house (about 3 months ago). 1 month after the works were complete, there started to be an overwhelming septic tank smell in the house. There is only one room affected by the smell at the top floor, but the smell is overwhelming.
This shows the ventilation pipe that runs the house, the exit at top of house, and the room impacted from the outside:
We’ve searched in vain, including even ripping out wall panelling in this room for what might be causing it but haven’t been able to track it down. The smell is only coming into this one room at the very top of the house and I’m wondering if it is because this room is the closest to the septic tank ventilation pipe? Any suggestions? I know the name of our septic tank system, it’s called the “Clear fox” https://clearfox.com/en/domestic-wastewater-treatment/ and the ventilation pipe from the system follows the house roof vertically before it exits into the air at a pipe chimney at the roof apex. This vertical ventilation pipe did not exist with the old ventilation system. I did a smoke test, and the smoke did seem to exit the ventilation pipe at the top without a problem..
The vendor says it’s an internal house problem (however there was no internal septic tank smell before his works) so he is trying to pass the problem to me.