Last night I touch two red wires and a part fell of my furnace. I was able to put the part back on but it must be broken to come off that easy. I think it is called a flame rollout switch or sensor. Should this fall away from its location?

Hi ostoughton and welcome, the rollout switch should have a mounting screw. How did you put "the part back on"? What were you doing in the combustion chamber anyway?

The switch may have simply fallen apart. I've had it happen several times. The switch needs to be replaced.