Trane SFSWT03533 Auxiliary Switch

The Trane SFSWT03533 Auxiliary Switch is a critical SPDT auxiliary switch designed for HVAC 20-60 Amp contactors. As the direct field replacement for the SWT3533, this genuine OEM part provides a single-pole, double-throw configuration featuring one normally open (NO) and one normally closed (NC) contact. Built for rugged industrial and commercial applications, it integrates seamlessly into Trane air conditioners, furnaces, and heat pumps to drive secondary logic functions like fan activation, interlock status, or alarm relays. Operating reliably within a 20V to 60V range, the unit employs standard 1/4” quick-connect terminals for rapid installation. Its compact 3-inch form factor ensures compatibility with high-amperage HVAC controls where space and high-duty cycle performance are paramount. Utilizing this replacement auxiliary switch restores original sequence of operations and prevents system downtime caused by failing or carbon-tracked secondary contacts in older mechanical switch assemblies.

• Direct OEM Compatibility: Engineered as the specific Trane SFSWT03533 replacement for SWT3533, ensuring perfect physical and electrical alignment.
• Versatile SPDT Logic: Features a 1 Normally Open/1 Normally Closed arrangement to manage external interlocks or pilot lights effectively.
• High Amperage Support: Specifically rated for integration with 20A through 60A HVAC contactors.
• Simplified Field Wiring: Equipped with standard 1/4" male spade quick-connect terminals to reduce labor time during service calls.
• Verified Performance: UL listed construction ensures safe operation within residential and commercial 24V-60V control circuits.

• How do I know if I need to replace my auxiliary switch? If your system compressor is running but the auxiliary fan or secondary status relay fails to engage, the internal contacts of your SFSWT03533 or SWT3533 may be pitted or failed.
• Can I use this switch on other brands of contactors? While designed for Trane equipment, this SPDT auxiliary switch fits most 20-60 amp contactors that accept standard side-mount or snap-on auxiliary blocks.
• What is the difference between SFSWT03533 and SWT3533? The SFSWT03533 is the current production OEM replacement, optimized for better longevity and direct compatibility with the legacy SWT3533 model.

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.