Report "I have a RHEEM RGPH-12EARJR unit that is 10 years old. I turned the unit on in Oct and it ran flawless for 2 months, then it stopped. I can manually start it by lightly pressing on a part of the furnace. It is a black round part that is about 2-3" in diameter on the left side. It has 2 wires going into it along with a red tube. What is this part called? And by replacing it, would it fix my issue? Any help would be appreciated"