Carrier HH18HV185 Limit Switch

The Carrier HH18HV185 is a high-precision 155-185F auto limit switch designed for critical thermal protection in heating and air conditioning systems. As an essential safety component, this disc-style HVAC limit switch replacement monitors ambient temperatures within the furnace or air handler, featuring a factory-calibrated cut-out temperature of 185°F. Upon reaching this threshold, the switch interrupts the electrical circuit to prevent heat exchanger damage and hazardous conditions. Once the temperature cools to the 155°F cut-in setpoint, the auto-reset functionality restores the circuit for continued operation. Engineered for 240V applications with a 5-amp rating, the Carrier HH18HV185 OEM part ensures seamless integration with internal blower motors and controls, maintaining strict compliance with manufacturer specifications. Relying on this genuine component prevents frequent system cycling and ensures your equipment operates within its designated thermal parameters.

• Thermal Protection: Prevents equipment failure by detecting overheating with a precise 185°F trip point.
• Automated Operation: Features an integrated auto-reset mechanism that cycles at 155°F, reducing manual intervention.
• OEM Compatibility: Designed specifically for Carrier, Bryant, and Payne units, ensuring electrical and physical fit.
• Compact Disc Design: Low-profile construction allows for reliable sensing in tight plenum and blower spaces.
• High Electrical Rating: Rated for up to 5 Amps at 240V, supporting standard residential and light commercial control circuits.

• What causes a Carrier HH18HV185 to trip? Common causes include restricted airflow from dirty filters, a failing blower motor, or oversized ductwork.
• Can this switch be used in 24V circuits? Yes, while rated for up to 240V, it is frequently used as a safety in 24V control loops.
• Is the HH18HV185 a normally closed switch? Yes, it maintains a normally closed (NC) state and opens only when the high-limit temperature is reached.

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.