White-Rodgers 3L11-190 Limit Switch

For service calls requiring a reliable thermal safety solution, the White-Rodgers 3L11-190 Limit Switch provides a high-performance 1/2" bimetal disc design that stops equipment overheating in its tracks. This SPST open on rise switch is engineered to break the electrical circuit when temperatures reach the 185 to 195 degrees F threshold, ensuring critical protection for furnaces and high-limit applications. As part of the Therm-O-Disc 36T21 series (Style 10857), it features a 30 degree F differential, allowing the system to reset automatically once the temperature drops back to a safe operating range around 155-165°F.

Built with technical durability in mind, the 3L11-190 includes 1/4" quick connect terminals and a loose ring stainless steel mounting bracket for universal snap disc compatibility and easy orientation in tight plenum spaces. Rated for 15A at 120VAC, this automatic reset limit control serves as a direct HVAC high limit replacement to restore system safety and prevent unnecessary downtime.

Key Benefits for Technicians:

• Precision Temperature Control: Fixed 185-195°F cut-out range provides consistent safety cut-off for residential and light commercial units.
• Universal Compatibility: The 1/2" disc footprint and loose ring bracket match standard OEM specifications across multiple furnace brands.
• Heavy-Duty Electrical Rating: Capable of handling inductive and resistive loads up to 15A at 120VAC, ensuring longevity under standard operation.
• Snap-Action Reliability: The Therm-O-Disc mechanism ensures high-speed contact separation to minimize arching and extend component life.

Common Questions:

What is the reset temperature for the 3L11-190?
Because this switch features a fixed 30°F differential, it will automatically reset (close the circuit) once the ambient temperature at the disc drops to approximately 155°F to 165°F.

Can this be used for fan control?
No. This is a "Limit" control (Open on Rise), meaning it breaks the circuit when it gets hot. Fan controls (Close on Rise) are designated by the "F" prefix, such as the 3F11 series.

Does the 3L11-190 replace other 36T21 style switches?
Yes, provided the cut-out temperature and differential match the requirements of the equipment being serviced. Always verify the manufacturer's specified temperature limits on the appliance nameplate.

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.