Hello everyone. I live in a small two-story cabin. After a day of below zero temps, I noticed a sewer odor in my downstairs bathroom. There is no window in the bathroom, just an exhaust fan. The sewer vent stack goes out the wall not through the roof, and it is located several feet away from the exhaust fan outlet. I’m wondering if the sewer vent stack is obstructed with ice. Nothing I can do about that tonight, but I am worried about sewer gas accumulating downstairs. I closed the bathroom door, but because of the freezing temperatures and the fact that I am heating with a space heater, I am worried about pipes freezing in the bathroom. (I did leave the water dripping in the sink.) I’m also worried about whether it’s dangerous to trap the sewer gas in the bathroom. Suggestions are much appreciated!

dump some anti-freeze down the stack to see if that frees it up? if in fact it is closed off with frost?
your trickling water in the sinks etc should maintain water in the traps to keep sewer gas out.