Carrier HH18HV110 Limit Switch

The Carrier HH18HV110 is a high-precision HVAC temperature limit switch designed for critical thermal protection in heating applications. This SPDT limit switch operates on an automatic reset logic, featuring a specific temperature range: it is engineered to open at 110°F and close at 90°F. As a genuine OEM Carrier part, the HH18HV110 ensures exact electrical matching for furnace and air handler control circuits, effectively preventing heat exchanger damage and optimizing system reliability in Carrier, Bryant, and Payne equipment. This 90-110F auto limit switch provides the rapid response necessary to interrupt the heating cycle if temperatures exceed the designated safety threshold. Modern contractors rely on this universal mounting HVAC switch for its versatility and durability in demanding commercial and residential environments. Integrating this temperature actuated switch into your service routine ensures compliance with original manufacturer specifications and maintains the operational integrity of the primary heating system.

• Precise Thermal Control: Features a calibrated 110°F open and 90°F close differential for accurate safety cycling.
• SPDT Configuration: Single Pole Double Throw design allows for versatile wiring in multiple control circuit architectures.
• Broad Compatibility: Fits a wide range of popular models, including 48LZ 008 521 and 579DEW series air handlers.
• OEM Construction: High-grade materials ensure long-term stability and resistance to thermal fatigue during high-cycle operations.

• What does the HH18HV110 limit switch do? It monitors the internal temperature of the HVAC unit and cuts power to the heating element or gas valve if the air reaches 110°F, resetting once it cools to 90°F.
• Is this an automatic or manual reset switch? This is an automatic reset limit switch, meaning it will re-engage the circuit without technician intervention once the unit cools to the lower set point.
• Can I use this switch in non-Carrier equipment? While designed as a Carrier OEM replacement part, it can be used in any application requiring an SPDT switch with a 110/90 degree thermal profile, provided mounting and electrical ratings match.

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.