White-Rodgers 3L09-16 Limit Switch

The White-Rodgers 3L09-16 is a professional-grade 1/2" bimetal disc limit switch engineered for critical temperature regulation in residential and commercial HVAC systems. This board-mounted limit control is built for high-speed contact separation, ensuring a rapid response when industrial safety thresholds are reached. It features a fixed open temperature of 150°F and a fixed close temperature of 130°F, operating on an open-on-rise switch action. With its 3.12" insertion length, it provides the necessary reach for accurate sensing in plenum or duct applications where standard surface mounts may fall short. The auto reset functionality eliminates the need for manual intervention after the system cools, making it a reliable choice for furnace high-limit protection. Its compact snap disc design and standard mounting holes allow for efficient field replacement on legacy and modern control boards.

• Precise Thermal Protection: Fixed 150°F trip point ensures system safety by cutting power to the burner or heating element during over-temperature conditions.
• Optimized Insertion Depth: The 3.12-inch probe length allows the bimetal disc to sit directly in the airflow for more reactive temperature monitoring.
• Automatic Reset Logic: Automatically re-engages at 130°F, reducing nuisance service calls while maintaining strict safety parameters.
• Durable Construction: High-speed contact separation extends the component lifecycle under standard electrical loads.

What does 'open on rise' mean for this limit switch?
This indicates the electrical circuit is broken (opened) when the ambient temperature hits 150°F to stop the heating process. The circuit reconnects (closes) once the temperature drops to 130°F.

Can I use the 3L09-16 as a universal replacement?
While it fits many board-mounted applications, you must verify the 150°F/130°F settings and the 3.12" insertion length match your original OEM specifications for safe operation.

Is this switch compatible with 24V or 120V circuits?
Yes, White-Rodgers 3F01 and 3L09 series snap discs are typically rated for use in both low-voltage control circuits and line-voltage applications, though you should always confirm the maximum amperage on the specific control board.

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.