“Just to note (for Yomim Tovim at least), if your oven has a pilot light (as opposed to an electric ignition), R’ Shachter holds that you can shut the oven or burner completely, because the flame isn’t being extinguished. It’s only being shrunk back down to the pilot. In such a case, for safety purposes, you should shut the burner whenever you’re not using it. “
Yes, I crack my windows open a bit, too, winter or summer.