Nordyne 626435R Limit Switch

The Nordyne 626435R Auto Limit Switch is a critical OEM safety component engineered for precision temperature monitoring in gas-fired and electric furnaces. This high-limit safety control features a 3-1/8 inch insert length and is calibrated to open between 200?F and 220?F. As a primary safety device, it prevents heat exchanger damage and hazardous conditions by interrupting the burner circuit if the plenum temperature exceeds specified tolerances. Designed as an automatic reset limit switch, it restores circuit continuity once temperatures drop back to safe operating levels. For technicians troubleshooting furnace short cycling or a blower motor running continuously, replacing a drifted or failed switch with this genuine Nordyne replacement part ensures the system adheres to original manufacturer specifications and safety protocols. This switch is a direct replacement for various Intertherm, Miller, and Nordyne air handlers and furnaces requiring a L220-20F fixed temperature response.

Key Benefits for HVAC Professionals

• Genuine OEM Replacement: Ensures exact fitment and electrical compatibility without the reliability risks of universal aftermarket alternatives.
• Internal Safety Protection: Protects the heat exchanger from thermal stress and potential cracks caused by restricted airflow or over-firing.
• Automatic Reset Functionality: Minimizes nuisance lockouts by allowing the system to resume operation once it returns to a safe thermal state.
• Defined Thermal Response: Specifically rated for a 200-220?F range to meet the specific static pressure and airflow requirements of compatible Nordyne cabinets.

Common Installation & Troubleshooting Questions

What causes a Nordyne 626435R to trip repeatedly?
While the switch itself may be failing, frequent tripping usually indicates an airflow restriction, such as a clogged filter, blocked return air grilles, or a failing blower motor. Always check secondary heat exchangers for soot buildup or obstructions.

Can I use a 5-inch insert if the 3-1/8 inch is out of stock?
No. The 3-1/8" insert length is specific to the depth of the plenum. Using a longer probe may interfere with internal components or place the sensor too close to the heat source, leading to inaccurate temperature readings and premature tripping.

Does this switch handle high-voltage or low-voltage circuits?
This limit control is typically wired into the 24V safety pilot circuit. Verify your specific wiring diagram to ensure the contact rating matches your furnace's control board requirements.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.