I'm trying to remember the title of this story where a space cadet is alone in space and is worried about his thermostat. It shows the correct temperature but he's convinced that it's wrong because he feels very hot. Throughout the story he becomes increasingly paranoid, and all his communication lines to his boss get cut off. The names are Russian, btw.
At the end of the story, he opens the doors to a capsule that just docked but there's nobody there.