Bard HVAC 8402-050 Limit Switch

The Bard HVAC 8402-050 Limit Switch is a high-precision safety component engineered for industrial and commercial HVAC systems. Calibrated for 150°F cut-out, this CO AUTO limit switch provides essential over-temperature protection to prevent heat exchanger damage and system failure. Featuring automatic reset functionality, it ensures continuous operation by restoring the circuit once the plenum temperature drops to a safe threshold, reducing unnecessary downtime for HVAC contractors and facilities managers.

Built with a rugged construction for high-cycle reliability, this 150F limit control is compatible with a wide range of Bard wall-mount units and air handlers. Its compact design allows for direct replacement in blower assemblies and furnace housings, ensuring accurate temperature sensing and safety circuit integrity. When troubleshooting Bard package units that are cycling on high limit or failing to engage the contactors, verifying the continuity and setpoint of the 8402-050 is a standard diagnostic step for veteran technicians.

• 150°F fixed setpoint provides reliable thermal protection against restricted airflow or blower failure.
• Automatic reset eliminates the need for manual intervention after a temporary over-temperature event.
• OEM-grade durability ensures long-term stability in demanding industrial HVAC environments.
• Standard spade terminal connections facilitate fast, drop-in replacement during service calls.
• Protects critical commercial refrigeration and manufacturing processes from heat-related damage.

• What does "CO AUTO" signify on this Bard switch? It indicates a "Close on" (automatic) reset logic where the switch opens at 150°F and closes automatically when the temperature cools.
• Is this switch compatible with 24V or 120V circuits? This limit switch is typically used in the 24V safety pilot circuit but is rated for standard limit switch voltages found in Bard systems; always check your specific wiring diagram.
• What are the symptoms of a failed 8402-050 limit switch? A common symptom is the indoor blower running while the burners or compressor fail to engage, or the unit cycling frequently due to high limit trips.

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.