Trane SWT1280 Limit Switch

The Trane SWT1280 Limit Switch is a high-reliability OEM thermal protection component specifically engineered for HVAC furnace safety and consistent air handler performance. This 3" insert limit switch serves as a critical fail-safe, monitoring supply plenum temperatures to prevent equipment damage. It is factory-calibrated with a 155°F opening point and an automatic reset that closes the circuit at 125°F. For field technicians, the SWT1280 is identical to C340056P18 and serves as a direct drop-in replacement for standard Trane and American Standard limit switches featuring a 3-inch probe depth.

Utilizing a robust snap-action mechanism, this automatic reset limit switch ensures precise temperature cut-outs, preventing short-cycling and protecting the heat exchanger from thermal stress. When diagnosing 4-flash error codes or intermittent blower operation, verify the SWT1280 technical specifications to ensure the 125-155F range aligns with the furnace's data plate requirements. This genuine Trane replacement part maintains original equipment tolerance and response times required for professional service standards.

• Precise Thermal Calibration: Engineered with a fixed 155-degree Fahrenheit trip point for accurate high-limit protection.
• OEM Compatibility: Replaces Trane part C340056P18 and SWT01280, ensuring seamless integration into existing control loops.
• Automatic Reset Function: Eliminates the need for manual intervention once the plenum temperature drops to the 125°F closing threshold.
• Standardized 3-Inch Probe: Designed for standard duct-mounted or plenum-mounted installation in residential and light commercial air handlers.

Is the SWT1280 the correct replacement for C340056P18?
Yes, the Trane SWT1280 limit switch is technically identical to the C340056P18 part number and can be used interchangeably in compatible equipment.

What causes this limit switch to trip repeatedly?
Frequent tripping is usually a symptom of restricted airflow, often caused by a dirty air filter, blocked return vents, or a failing blower motor. Always check system pressure before replacing the switch.

Can I use a higher temperature limit switch instead of the SWT1280?
Contractors should never substitute a limit switch with a higher temperature rating than specified by the manufacturer, as this bypasses critical safety thresholds designed to prevent heat exchanger failure.

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.