White-Rodgers 3L11-180 Limit Switch

The White-Rodgers 3L11-180 Limit Switch is a high-performance 1/2" bimetal disc limit switch designed for critical thermal protection in HVAC and appliance systems. As an automatic reset snap disc thermostat, this component features a Single Pole Single Throw (SPST) configuration with an open on rise switch action. Engineered to trigger between 175°F and 185°F, it maintains a narrow operating window to prevent system overheating, resetting automatically once the temperature drops by the 30°F differential. This universal mini limit switch utilizes an aluminum disc cup for rapid heat transfer and a stainless steel mounting bracket for secure installation in high-heat environments like furnaces and boilers.

For industrial applications, the Emerson 3L11-180 (Therm-O-Disc 36T21-10855) supports electrical loads up to 15A at 120VAC and 10A at 240VAC. The snap-action mechanism ensures high-speed contact separation, reducing internal arcing and extending the functional life of your furnace high limit control. Standard 1/4" quick connect terminals facilitate straightforward wiring for field replacements or new installations across various HVAC temperature controls.

• Precise Thermal Cutoff: Fixed 180-degree setpoint provides reliable high-limit protection for heating equipment.
• Automatic Reset Logic: Eliminates the need for manual intervention by re-engaging the circuit once temperatures stabilize.
• Durable Construction: Features a corrosion-resistant stainless steel bracket and 1/2" bimetal disc for long-term cycle performance.
• Broad Compatibility: Replaces numerous OEM 36T21 and L180 styles, making it a staple for service van inventory.

• What does "Open on Rise" mean for this switch? The contacts remain closed under normal conditions but snap open to break the circuit when the temperature reaches the 175-185°F range.
• Can I use this for a blower fan control? No, fan controls typically require "Close on Rise" action (3F series); this 3L series is strictly for high-limit safety shutoff.
• Is this switch compatible with 240V systems? Yes, it is rated for both 120VAC and 240VAC applications with a 10A rating at the higher voltage.

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.