grady
New Member
I've been investigating a sewer gas smell in my shop for several years. The smell starts in fall when temps will drop below 40, not necessarily freezing. Checked vent pipes, checked drains, changed toilet seal, etc.. to no avail. Really started thinking it was a vent pipe connection drying out with the lower humidity or some sort of drain siphoning from negative pressure. Finally did a crude smoke test this morning. Removed p trap, smoke bomb in shop vac connected to a sink drain. Immediately noticed smoke coming out of toilet bowl right under the lip where the water enters up flushing.
My guess is that it is bad toilet casting and the smoke filtered through that smaller hole that is a remnant of how the toilet was cast. If smoke can make it through here, surely sewer gas can. I don't know how else smoke could have made it through to the bowl, even if the wax seal was bad. So, is it a bad toilet casting that only acts up when the barometric pressure rises as temps drop and the sewer gas is looking for an easier route out than the roof vent? Could I just caulk this small hole or better to buy a new toilet? For now, I've got the toilet off, drain hole plugged and sealed up so we'll see if the smell returns after it gets cold again at night. Thanks for any insight.
My guess is that it is bad toilet casting and the smoke filtered through that smaller hole that is a remnant of how the toilet was cast. If smoke can make it through here, surely sewer gas can. I don't know how else smoke could have made it through to the bowl, even if the wax seal was bad. So, is it a bad toilet casting that only acts up when the barometric pressure rises as temps drop and the sewer gas is looking for an easier route out than the roof vent? Could I just caulk this small hole or better to buy a new toilet? For now, I've got the toilet off, drain hole plugged and sealed up so we'll see if the smell returns after it gets cold again at night. Thanks for any insight.