Lochinvar & A.O. Smith 100074280 Limit Switch
The Lochinvar & A.O. Smith 100074280 High Limit Switch is a critical safety component engineered to provide thermal protection in high-efficiency heating systems. Designed as a genuine OEM replacement part, this switch monitors the internal temperature of the heat exchanger or burner door to prevent unsafe operating conditions. If temperatures exceed the factory-defined safety threshold, the 100074280 triggers an immediate system lockout to mitigate the risk of equipment damage. This fixed-temperature limit switch is widely utilized in Lochinvar Knight boilers, A.O. Smith performance water heaters, and Takagi tankless units, ensuring seamless integration with existing control boards and wiring harnesses. For service contractors, installing this genuine 100074280 switch is essential for maintaining the mechanical integrity of the combustion chamber and meeting specific safety compliance standards in residential and commercial hydronic systems. Its precision-calibrated thermal response ensures that the system handles peak thermal loads without premature nuisance tripping.
Key Benefits
- Ensures boiler safety by providing a reliable fail-safe against overheating and potential heat exchanger failure.
- Designed for direct OEM compatibility with Lochinvar, A.O. Smith, and Takagi heating equipment, eliminating the need for field modifications.
- Features a high-precision bimetal sensor for accurate temperature detection and rapid response times.
- Simple two-wire connection allows for fast installation during emergency service calls.
- Constructed with durable mounting brackets to withstand the high-vibration environment of modern burner assemblies.
Common Questions
Is the 100074280 a manual reset or automatic reset switch?
This specific model is typically an automatic reset limit switch; however, if the system control board detects a high-limit trip, the boiler itself may require a manual reset at the interface to clear the fault code for safety reasons.
What causes this high limit switch to trip repeatedly?
Repeated tripping usually indicates restricted water flow, scaling within the heat exchanger, or a failing circulating pump. It is critical to diagnose the cause of the overheat condition rather than just replacing the sensor.
Can I use a universal limit switch instead of the 100074280?
Using a genuine 100074280 is highly recommended, as universal switches may have different temperature set-points or differential ratings, which can compromise the safety and performance of the specific HVAC or water heating unit.
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: $11.97
-65%$11.97
$4.19Lochinvar & A.O. Smith 100074280 Limit Switch
The Lochinvar & A.O. Smith 100074280 High Limit Switch is a critical safety component engineered to provide thermal protection in high-efficiency heating systems. Designed as a genuine OEM replacement part, this switch monitors the internal temperature of the heat exchanger or burner door to prevent unsafe operating conditions. If temperatures exceed the factory-defined safety threshold, the 100074280 triggers an immediate system lockout to mitigate the risk of equipment damage. This fixed-temperature limit switch is widely utilized in Lochinvar Knight boilers, A.O. Smith performance water heaters, and Takagi tankless units, ensuring seamless integration with existing control boards and wiring harnesses. For service contractors, installing this genuine 100074280 switch is essential for maintaining the mechanical integrity of the combustion chamber and meeting specific safety compliance standards in residential and commercial hydronic systems. Its precision-calibrated thermal response ensures that the system handles peak thermal loads without premature nuisance tripping.
Key Benefits
- Ensures boiler safety by providing a reliable fail-safe against overheating and potential heat exchanger failure.
- Designed for direct OEM compatibility with Lochinvar, A.O. Smith, and Takagi heating equipment, eliminating the need for field modifications.
- Features a high-precision bimetal sensor for accurate temperature detection and rapid response times.
- Simple two-wire connection allows for fast installation during emergency service calls.
- Constructed with durable mounting brackets to withstand the high-vibration environment of modern burner assemblies.
Common Questions
Is the 100074280 a manual reset or automatic reset switch?
This specific model is typically an automatic reset limit switch; however, if the system control board detects a high-limit trip, the boiler itself may require a manual reset at the interface to clear the fault code for safety reasons.
What causes this high limit switch to trip repeatedly?
Repeated tripping usually indicates restricted water flow, scaling within the heat exchanger, or a failing circulating pump. It is critical to diagnose the cause of the overheat condition rather than just replacing the sensor.
Can I use a universal limit switch instead of the 100074280?
Using a genuine 100074280 is highly recommended, as universal switches may have different temperature set-points or differential ratings, which can compromise the safety and performance of the specific HVAC or water heating unit.
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.
Product Information
Product Information
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Description
The Lochinvar & A.O. Smith 100074280 High Limit Switch is a critical safety component engineered to provide thermal protection in high-efficiency heating systems. Designed as a genuine OEM replacement part, this switch monitors the internal temperature of the heat exchanger or burner door to prevent unsafe operating conditions. If temperatures exceed the factory-defined safety threshold, the 100074280 triggers an immediate system lockout to mitigate the risk of equipment damage. This fixed-temperature limit switch is widely utilized in Lochinvar Knight boilers, A.O. Smith performance water heaters, and Takagi tankless units, ensuring seamless integration with existing control boards and wiring harnesses. For service contractors, installing this genuine 100074280 switch is essential for maintaining the mechanical integrity of the combustion chamber and meeting specific safety compliance standards in residential and commercial hydronic systems. Its precision-calibrated thermal response ensures that the system handles peak thermal loads without premature nuisance tripping.
Key Benefits
- Ensures boiler safety by providing a reliable fail-safe against overheating and potential heat exchanger failure.
- Designed for direct OEM compatibility with Lochinvar, A.O. Smith, and Takagi heating equipment, eliminating the need for field modifications.
- Features a high-precision bimetal sensor for accurate temperature detection and rapid response times.
- Simple two-wire connection allows for fast installation during emergency service calls.
- Constructed with durable mounting brackets to withstand the high-vibration environment of modern burner assemblies.
Common Questions
Is the 100074280 a manual reset or automatic reset switch?
This specific model is typically an automatic reset limit switch; however, if the system control board detects a high-limit trip, the boiler itself may require a manual reset at the interface to clear the fault code for safety reasons.
What causes this high limit switch to trip repeatedly?
Repeated tripping usually indicates restricted water flow, scaling within the heat exchanger, or a failing circulating pump. It is critical to diagnose the cause of the overheat condition rather than just replacing the sensor.
Can I use a universal limit switch instead of the 100074280?
Using a genuine 100074280 is highly recommended, as universal switches may have different temperature set-points or differential ratings, which can compromise the safety and performance of the specific HVAC or water heating unit.
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.
