Fix how? What's the problem your having? If it's doing the quest you have to head downstairs into the basement and craft a Heating Element.
Sorry for taking so long to respond. From what I know you should have gotten the ability to make the Heating element from Leslie. She should have given you something like a book that automatically adds the recipe. I'm not saying you did, but I missed the recipe several times at first in my crafting bench cause I kept reading over it. If you haven't got the event where she gave you the crafting book, again it automatically adds the recipe so you don't need to read it, then you need to talk to her either during the morning or midday, can't remember which to get it.