The Rheem Manufacturing Company–Ruud 47-22860-01 Auto Reset Limit Switch (105°F Open, 95°F Close) is a temperature-activated safety control designed to regulate and protect HVAC systems from excessive heat. It automatically opens the electrical circuit at 105°F to stop operation and closes at 95°F once temperatures return to normal. https://www.partshnc.com/limit-switch-1050p-95cl-for-rheem-ruud-part-47-22860-01