Weirdest thing. We started getting a real pungent odor of rotten eggs in the basement and also on the first floor near the bathroom. She was cleaning the bathroom and flushed the toilet, so the smell started after that. Nothing is backed up and no leaks (that I can see). I called a plumber and he said he could not come out until Monday or Tuesday. For the heck of it, I flushed the toilet again and the smell stopped and so far hasn't come back. We have had EXCESSIVE heat here. The temps yesterday where 108 with a real feel of 118. Any idea what could cause this? Could the heat have something to do with it?