Lochinvar & A.O. Smith 100187858 Switch
The Lochinvar & A.O. Smith 100187858 Blower Prover Switch is a critical safety component designed for high-efficiency gas-fired boilers and commercial water heaters. This 1.0" WC air pressure switch serves as a high-limit safety device, ensuring the combustion air blower is generating sufficient airflow before allowing many Lochinvar Knight or A.O. Smith Cyclone models to proceed with the ignition sequence. Acting as a OEM replacement pressure switch, the 100187858 is the direct substitute for the NS2-1333-02, featuring a precise set point that monitors the pressure differential across the blower housing. By utilizing a durable internal diaphragm and a normally open contact configuration, this HVAC blower prover prevents hazardous gas accumulation by halting the gas valve if flue obstructions or blower mechanical failures occur. For contractors, this part offers a drop-in fit with a standard 1-inch connection, maintaining system modulating boiler performance and safety compliance without the need for field recalibration.
Key Benefits- Direct OEM Compatibility: Engineered as a precise replacement for NS2-1333-02, ensuring seamless integration with existing Lochinvar and A.O. Smith control logic.
- Enhanced System Safety: Prevents ignition under restricted vent conditions or blower failure, protecting heat exchangers from overheating and ensuring proper exhaust scavenging.
- Industrial-Grade Reliability: Features a robust casing designed to withstand the high-temperature environments of commercial mechanical rooms and continuous cycle operations.
- Simplified Field Service: Standard 1.0" connection and lightweight 0.3 lb design allow for rapid installation, reducing diagnostic time for blower prover error codes.
What causes a blower prover switch to stay open during the ignition cycle?
An open switch usually indicates insufficient vacuum/pressure from the blower, often caused by a blocked intake, obstructed flue, cracked sensing tubing, or a failing blower motor that cannot reach the required 1.0" WC threshold.
Is the 100187858 interchangeable with other pressure settings?
No. HVAC safety switches are calibrated to specific "Inches of Water Column" (WC) ratings required by the appliance manufacturer. Using a switch with a different set point can lead to unsafe operation or frequent nuisance lockouts.
How can I test if my current switch is defective?
Technicians should use a manometer to verify the actual pressure produced by the blower and a multimeter to check the continuity of the switch contacts when that pressure is applied. If the pressure exceeds 1.0" WC but the circuit remains open, the switch requires replacement.
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: $66.19
-65%$66.19
$23.17Lochinvar & A.O. Smith 100187858 Switch
The Lochinvar & A.O. Smith 100187858 Blower Prover Switch is a critical safety component designed for high-efficiency gas-fired boilers and commercial water heaters. This 1.0" WC air pressure switch serves as a high-limit safety device, ensuring the combustion air blower is generating sufficient airflow before allowing many Lochinvar Knight or A.O. Smith Cyclone models to proceed with the ignition sequence. Acting as a OEM replacement pressure switch, the 100187858 is the direct substitute for the NS2-1333-02, featuring a precise set point that monitors the pressure differential across the blower housing. By utilizing a durable internal diaphragm and a normally open contact configuration, this HVAC blower prover prevents hazardous gas accumulation by halting the gas valve if flue obstructions or blower mechanical failures occur. For contractors, this part offers a drop-in fit with a standard 1-inch connection, maintaining system modulating boiler performance and safety compliance without the need for field recalibration.
Key Benefits- Direct OEM Compatibility: Engineered as a precise replacement for NS2-1333-02, ensuring seamless integration with existing Lochinvar and A.O. Smith control logic.
- Enhanced System Safety: Prevents ignition under restricted vent conditions or blower failure, protecting heat exchangers from overheating and ensuring proper exhaust scavenging.
- Industrial-Grade Reliability: Features a robust casing designed to withstand the high-temperature environments of commercial mechanical rooms and continuous cycle operations.
- Simplified Field Service: Standard 1.0" connection and lightweight 0.3 lb design allow for rapid installation, reducing diagnostic time for blower prover error codes.
What causes a blower prover switch to stay open during the ignition cycle?
An open switch usually indicates insufficient vacuum/pressure from the blower, often caused by a blocked intake, obstructed flue, cracked sensing tubing, or a failing blower motor that cannot reach the required 1.0" WC threshold.
Is the 100187858 interchangeable with other pressure settings?
No. HVAC safety switches are calibrated to specific "Inches of Water Column" (WC) ratings required by the appliance manufacturer. Using a switch with a different set point can lead to unsafe operation or frequent nuisance lockouts.
How can I test if my current switch is defective?
Technicians should use a manometer to verify the actual pressure produced by the blower and a multimeter to check the continuity of the switch contacts when that pressure is applied. If the pressure exceeds 1.0" WC but the circuit remains open, the switch requires replacement.
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 100187858 Blower Prover Switch is a critical safety component designed for high-efficiency gas-fired boilers and commercial water heaters. This 1.0" WC air pressure switch serves as a high-limit safety device, ensuring the combustion air blower is generating sufficient airflow before allowing many Lochinvar Knight or A.O. Smith Cyclone models to proceed with the ignition sequence. Acting as a OEM replacement pressure switch, the 100187858 is the direct substitute for the NS2-1333-02, featuring a precise set point that monitors the pressure differential across the blower housing. By utilizing a durable internal diaphragm and a normally open contact configuration, this HVAC blower prover prevents hazardous gas accumulation by halting the gas valve if flue obstructions or blower mechanical failures occur. For contractors, this part offers a drop-in fit with a standard 1-inch connection, maintaining system modulating boiler performance and safety compliance without the need for field recalibration.
Key Benefits- Direct OEM Compatibility: Engineered as a precise replacement for NS2-1333-02, ensuring seamless integration with existing Lochinvar and A.O. Smith control logic.
- Enhanced System Safety: Prevents ignition under restricted vent conditions or blower failure, protecting heat exchangers from overheating and ensuring proper exhaust scavenging.
- Industrial-Grade Reliability: Features a robust casing designed to withstand the high-temperature environments of commercial mechanical rooms and continuous cycle operations.
- Simplified Field Service: Standard 1.0" connection and lightweight 0.3 lb design allow for rapid installation, reducing diagnostic time for blower prover error codes.
What causes a blower prover switch to stay open during the ignition cycle?
An open switch usually indicates insufficient vacuum/pressure from the blower, often caused by a blocked intake, obstructed flue, cracked sensing tubing, or a failing blower motor that cannot reach the required 1.0" WC threshold.
Is the 100187858 interchangeable with other pressure settings?
No. HVAC safety switches are calibrated to specific "Inches of Water Column" (WC) ratings required by the appliance manufacturer. Using a switch with a different set point can lead to unsafe operation or frequent nuisance lockouts.
How can I test if my current switch is defective?
Technicians should use a manometer to verify the actual pressure produced by the blower and a multimeter to check the continuity of the switch contacts when that pressure is applied. If the pressure exceeds 1.0" WC but the circuit remains open, the switch requires replacement.
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.
