Actually, its kinda funny... before we first got into worming, my aunt had brought a cup of red wrigglers from her worm farms for my little brother as a Christmas gift. She explained to him how to care for them, as well as the beneifts they bring to your garden. My dad helped him set up a tub and the worms were on their way. However, my little brother was not ever even interested in gardening and neglected the worms... While I was off at school my dad was the one who essentially was in charge of the worms, and being a very very busy man, he basically neglected them as well. For the entire winter, from thanksgiving to may, the worms subsisted in a very hot room of our house in a tub with only a few small holes in the lid. The only food the worms recieved for that entire period was coffee grounds and filters. That is it!!! When spring came along, I returned home for summer break. I wanted to start my own worm farm(s), because I was/am an avid gardener. When I pulled that worm farm out of that hot room and opened it up fully for the first time in months, I was amazed to see a huge mass of thriving, writhing worms!!!! The worms were packed solid. There were so many worms it was ridiculous. There may have been more worms in that tub than I have in all of my worm farms combined. It was freakish. So the point is, that heat of which you speak is something the worms love. Those worms were in a room that stayed about 80 degrees and were fed only coffee grounds.
Now I have 6 worm farms of my own!!! I feed them a huge diversity of things... and of course, every day one of the bins gets its morning coffee ;-)