Westinghouse 626618 Furnace Main Limit Switch 0.5 Inch

Product Description

The WESTINGHOUSE 626618 is a main limit switch designed for use in gas furnace systems. Limit switches are safety control components that monitor heat exchanger temperatures and interrupt the burner circuit when a preset high-temperature threshold is detected, preventing overheating and potential heat exchanger damage. This switch features a 0.5 inch diameter form factor, a common size for residential furnace applications. It is a direct-replacement component typically installed by licensed HVAC technicians during routine maintenance or safety-system repairs.

This limit switch is suited for gas furnace installations where the existing main limit switch has failed or is outside calibration. Limit switches of this type are found on the furnace plenum or heat exchanger housing and are a standard component in forced-air heating systems. The 0.5 inch diameter mounting profile matches a widely used configuration in residential and light-commercial furnace equipment.

Key Features

• 0.5 inch diameter mounting profile for standard furnace limit switch cutouts
• Functions as a high-temperature safety control to protect the heat exchanger
• Interrupts burner operation when overtemperature conditions are detected
• Direct OEM-style replacement for failed or out-of-spec main limit switches

Compatibility

Designed as an OEM-style replacement main limit switch for residential gas furnace applications where a 0.5 inch diameter limit switch is specified.

Installation Notes

Installation should be performed by a licensed HVAC technician in accordance with applicable local mechanical codes and the furnace manufacturer service documentation. Shut off all electrical power and close the gas supply valve to the furnace before removing the existing limit switch. Verify the replacement switch orientation and wiring terminal positions match the original before energizing the system. After installation, cycle the furnace and confirm normal limit switch operation before returning the unit to service.

Technical Specifications

• Component Type: Main Limit Switch
• Mounting Diameter: 0.5 inches
• Application: Furnace

Standard Information

• Brand: WESTINGHOUSE
• Manufacturer Part Number: 626618