Lochinvar & A.O. Smith 100074412 High Limit Switch

The Lochinvar & A.O. Smith 100074412 High Limit Switch is a temperature control component used to monitor heat levels inside boilers and water heating equipment. It is designed to respond when internal temperatures rise beyond a set limit by interrupting the electrical circuit, allowing the system to return to a stable operating range. In HVAC systems, this part is commonly found in units where consistent thermal regulation is required during operation. It is positioned within the control section of the appliance and supports controlled heat management during combustion and recovery cycles to maintain steady operating conditions.