Carrier HH680352 Limit Switch

The Carrier HH680352 Limit Switch is a critical safety component designed for precise thermal monitoring in high-output HVAC systems. Engineered for high-temperature furnace and air handler applications, this 190-degree thermal limit switch features a 20-degree close differential, ensuring the burner circuit or blower motor cycles correctly to prevent over-temperature conditions. As a genuine Carrier OEM replacement part, it maintains factory performance standards and ensures HVAC system safety by cutting power to the gas valve when the heat exchanger cabinet exceeds calibrated limits. This specific furnace limit control is compatible with a wide range of Carrier, Bryant, and Day & Night equipment, providing a reliable solution for technicians troubleshooting high-limit trips or intermittent ignition failures. When installing this automatic reset limit switch, utilize the standard 1/4-inch spade terminals for secure electrical continuity and verify the temperature rating matches the original equipment specification for optimal system protection.

• Fixed Temperature Setting: Opens at 190°F (88°C) to protect the heat exchanger from thermal stress.
• Precise Differential: Closes at 170°F (77°C), providing a consistent 20-degree reset window for stable operation.
• Direct OEM Fit: Drop-in replacement for the HH680352, eliminating the need for mounting modifications in the field.
• Professional Grade Durability: Constructed to withstand the high-vibration and high-heat environments of commercial and residential furnaces.
• Safety Compliance: Meets manufacturer safety protocols for preventing cabinet overheating and potential fire hazards.

Why is my furnace tripping the limit switch?
Repeated trips at 190°F typically indicate restricted airflow. Check for a dirty HVAC filter, a failing blower motor, or blocked return air registers before replacing the sensor.

Is the HH680352 an manual or automatic reset switch?
This model is an automatic reset limit switch. It will close the circuit once the plenum temperature drops 20 degrees below the opening setpoint.

Can I bypass this switch for testing purposes?
Never bypass a safety limit switch permanently. Technicians may use a temporary jumper for diagnostic continuity checks only, but the unit must not be left running without a functional limit control.

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.