This is a brand new OEM Carrier Bryant Payne upgraded Furnace Disc Limit Switch. It is a direct replacement for Carrier Bryant Payne. It replaces the part numbers listed below. A limit switch is a safety device designed to shut down a piece of equipment. Limits have a set point, which is in some cases, adjustable. Replaces Old Part #s. Partial List of Units that Use This Item. Hit Ctrl + F and enter your model number for a quick search!