I'm not mining really with S3's anymore. Costs more than profits. But they are good heaters.
Thats what my buddy does with his KnC cubes; put em in corners of house to heat it up a little.
For my "at home rig" (some SP20's) I did the same as well. When it was cold; turned them to blow into the house. When it got hot; turn em back to blow out the window again.