Carrier HH18HA017 Limit Switch
The Carrier HH18HA017 is a critical safety component designed for precise thermal management in high-performance HVAC systems. This L170-40F limit switch functions as a primary high-limit control, monitoring the heat exchanger or plenum temperatures to prevent equipment damage. When the internal temperature reaches the 170°F threshold, the internal bimetal disc interrupts the electrical circuit to the burner or heating elements. As the system cools to 130°F (a 40°F differential), the automatic reset furnace switch restores the circuit, ensuring continuous operational cycles without manual intervention. As an OEM Carrier replacement part, it guarantees exact fitment and calibration, maintaining the original engineering specifications of Carrier, Bryant, and Payne air handlers and furnaces. For contractors, using this HVAC temperature safety switch eliminates the risk of premature component failure and ensures compliance with factory safety standards. Its 4-inch insertion depth is engineered for optimal airflow exposure, providing the rapid response required for modern high-efficiency climate control equipment.
Key Benefits- Factory Calibrated Precision: Features a 170°F open and 130°F close setpoint to maintain tight operational tolerances.
- Automatic Reset Logic: Eliminates nuisance service calls by automatically restoring system power once temperatures return to a safe range.
- OEM Compatibility: Seamlessly integrates with Carrier, Bryant, and Payne residential and commercial heating units.
- Enhanced Equipment Protection: Prevents heat exchanger cracking and thermal stress by strictly enforcing temperature ceilings.
When should a technician replace the HH18HA017 limit switch?
Replace the switch if you diagnose an open circuit during normal heating cycles when the temperature is below 170°F, or if the switch fails to close consistently at the 130°F reset point during troubleshooting.
Is this switch compatible with multi-stage furnaces?
Yes, this primary limit control is compatible with various multi-stage systems, provided the original specifications call for an L170-40F thermal profile and 4-inch mounting depth.
Does this part require a specific mounting orientation?
Follow the original equipment manufacturer’s instruction for airflow direction; however, the sensor must be fully inserted into the airstream to ensure accurate temperature sensing.
Item is Non Cancelable / Non Returnable
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.
Original: $36.84
-65%$36.84
$12.89Carrier HH18HA017 Limit Switch
The Carrier HH18HA017 is a critical safety component designed for precise thermal management in high-performance HVAC systems. This L170-40F limit switch functions as a primary high-limit control, monitoring the heat exchanger or plenum temperatures to prevent equipment damage. When the internal temperature reaches the 170°F threshold, the internal bimetal disc interrupts the electrical circuit to the burner or heating elements. As the system cools to 130°F (a 40°F differential), the automatic reset furnace switch restores the circuit, ensuring continuous operational cycles without manual intervention. As an OEM Carrier replacement part, it guarantees exact fitment and calibration, maintaining the original engineering specifications of Carrier, Bryant, and Payne air handlers and furnaces. For contractors, using this HVAC temperature safety switch eliminates the risk of premature component failure and ensures compliance with factory safety standards. Its 4-inch insertion depth is engineered for optimal airflow exposure, providing the rapid response required for modern high-efficiency climate control equipment.
Key Benefits- Factory Calibrated Precision: Features a 170°F open and 130°F close setpoint to maintain tight operational tolerances.
- Automatic Reset Logic: Eliminates nuisance service calls by automatically restoring system power once temperatures return to a safe range.
- OEM Compatibility: Seamlessly integrates with Carrier, Bryant, and Payne residential and commercial heating units.
- Enhanced Equipment Protection: Prevents heat exchanger cracking and thermal stress by strictly enforcing temperature ceilings.
When should a technician replace the HH18HA017 limit switch?
Replace the switch if you diagnose an open circuit during normal heating cycles when the temperature is below 170°F, or if the switch fails to close consistently at the 130°F reset point during troubleshooting.
Is this switch compatible with multi-stage furnaces?
Yes, this primary limit control is compatible with various multi-stage systems, provided the original specifications call for an L170-40F thermal profile and 4-inch mounting depth.
Does this part require a specific mounting orientation?
Follow the original equipment manufacturer’s instruction for airflow direction; however, the sensor must be fully inserted into the airstream to ensure accurate temperature sensing.
Item is Non Cancelable / Non Returnable
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.
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Description
The Carrier HH18HA017 is a critical safety component designed for precise thermal management in high-performance HVAC systems. This L170-40F limit switch functions as a primary high-limit control, monitoring the heat exchanger or plenum temperatures to prevent equipment damage. When the internal temperature reaches the 170°F threshold, the internal bimetal disc interrupts the electrical circuit to the burner or heating elements. As the system cools to 130°F (a 40°F differential), the automatic reset furnace switch restores the circuit, ensuring continuous operational cycles without manual intervention. As an OEM Carrier replacement part, it guarantees exact fitment and calibration, maintaining the original engineering specifications of Carrier, Bryant, and Payne air handlers and furnaces. For contractors, using this HVAC temperature safety switch eliminates the risk of premature component failure and ensures compliance with factory safety standards. Its 4-inch insertion depth is engineered for optimal airflow exposure, providing the rapid response required for modern high-efficiency climate control equipment.
Key Benefits- Factory Calibrated Precision: Features a 170°F open and 130°F close setpoint to maintain tight operational tolerances.
- Automatic Reset Logic: Eliminates nuisance service calls by automatically restoring system power once temperatures return to a safe range.
- OEM Compatibility: Seamlessly integrates with Carrier, Bryant, and Payne residential and commercial heating units.
- Enhanced Equipment Protection: Prevents heat exchanger cracking and thermal stress by strictly enforcing temperature ceilings.
When should a technician replace the HH18HA017 limit switch?
Replace the switch if you diagnose an open circuit during normal heating cycles when the temperature is below 170°F, or if the switch fails to close consistently at the 130°F reset point during troubleshooting.
Is this switch compatible with multi-stage furnaces?
Yes, this primary limit control is compatible with various multi-stage systems, provided the original specifications call for an L170-40F thermal profile and 4-inch mounting depth.
Does this part require a specific mounting orientation?
Follow the original equipment manufacturer’s instruction for airflow direction; however, the sensor must be fully inserted into the airstream to ensure accurate temperature sensing.
Item is Non Cancelable / Non Returnable
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.
