Westinghouse 626446R Furnace Limit Switch 140F Auto Reset

Product Description

The WESTINGHOUSE 626446R is a furnace limit switch designed to protect heating systems from overheating conditions. It operates with a 140 degrees F trip point and a 120 degrees F reset point, functioning as an automatic-reset safety device. The switch features a 3-inch insert style mounting and is rated for single-speed applications. Licensed HVAC technicians install this component as part of routine furnace safety system maintenance or repair. It interrupts the burner circuit when plenum or heat exchanger temperatures exceed the rated setpoint, then resets automatically once temperatures return to the safe range.

This limit switch is suited for residential gas furnace applications where an insert-style limit switch is required. It is a direct replacement component for furnaces using a 3-inch insertion depth limit switch with 140 degrees F trip and 120 degrees F reset ratings. Typical installations include upflow, downflow, and horizontal gas furnaces that rely on disk-style or cartridge-style limit controls for high-temperature safety shutoff.

Key Features

• 140 degrees F trip point with 120 degrees F automatic reset — no manual reset required after thermal event
• 3-inch insert depth for standard furnace plenum or heat exchanger mounting
• 1/2-degree sensing differential for precise temperature control
• Single-speed rated for compatibility with standard furnace blower configurations
• Auto-reset design reduces service callbacks after nuisance trips caused by airflow restrictions

Compatibility

Designed as an OEM-style replacement for residential gas furnaces requiring a 3-inch insert limit switch with a 140 degrees F open and 120 degrees F close setpoint.

Installation Notes

Installation should be performed by a licensed HVAC technician. Always shut off electrical power at the disconnect or breaker and turn off the gas supply before removing or installing a limit switch. The switch must be seated fully to the specified insertion depth to ensure accurate temperature sensing. Refer to the furnace wiring diagram and applicable local mechanical codes when completing the repair.

Technical Specifications

• Type: Limit Switch
• Trip Temperature: 140 degrees F
• Reset Temperature: 120 degrees F
• Reset Type: Automatic
• Insert Depth: 3 inches
• Sensing Differential: 1/2 degree F
• Speed Rating: 1-Speed
• Application: Furnace

Standard Information

• Brand: WESTINGHOUSE
• Manufacturer Part Number: 626446R