Lochinvar & A.O. Smith 100208408 Pressure Switch
The Lochinvar & A.O. Smith 100208408 Pressure Switch is a critical safety component designed for high-efficiency boilers and water heaters. As a low air pressure switch, its primary function is to monitor the differential pressure within the combustion chamber and venting system. Specifically engineered as an OEM replacement part, the 100208408 ensures that the inducer blower is generating sufficient airflow to safely exhaust flue gases and support proper combustion. If the system detects a drop in pressure below the calibrated set point—often caused by venting obstructions, a failing blower motor, or restricted air intakes—the switch interrupts the ignition sequence to prevent faulty combustion or hazardous CO buildup. This HVAC safety switch features a robust diaphragm and precise electrical contacts (Common, Normally Open, Normally Closed) to provide reliable feedback to the integrated control module. For technicians troubleshooting Lochinvar boiler error codes related to "APS Open" or "Air Pressure SW," this genuine component is the standard for restoring system sequence of operation and maintaining high-efficiency HVAC performance.
Key Benefits- Precise Differential Sensing: Accurately monitors negative pressure to ensure the inducer fan is operating within manufacturer specifications.
- System Safety Integration: Acts as a primary fail-safe, preventing gas valve energization if exhaust venting is compromised.
- OEM Compatibility: Guaranteed fit and function for specific Lochinvar and A.O. Smith models, eliminating the calibration risks associated with universal switches.
- Durable Construction: Built to withstand the thermal cycling and moisture levels common in high-efficiency condensing environments.
What causes a "Low Air" or "APS Open" fault code?
While a faulty 100208408 pressure switch can be the culprit, technicians should first inspect for blocked PVC intake/exhaust pipes, cracked silicone reference tubing, or debris in the inducer housing that prevents the switch from closing.
Can I use a universal pressure switch instead of the 100208408?
It is not recommended. This low air pressure switch is factory-calibrated to a specific "inches of water column" (WC) set point unique to the heat exchanger’s airflow requirements. Using an incorrect part can lead to nuisance tripping or unsafe operating conditions.
How do I test the 100208408 switch in the field?
With the blower running, use a manometer to verify the actual pressure reaching the switch and a multimeter to check for continuity across the contacts. If the pressure meets the set point but the switch remains open, a replacement is necessary.
This item is not eligible for free shipping.
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: $115.90
-65%$115.90
$40.56Lochinvar & A.O. Smith 100208408 Pressure Switch
The Lochinvar & A.O. Smith 100208408 Pressure Switch is a critical safety component designed for high-efficiency boilers and water heaters. As a low air pressure switch, its primary function is to monitor the differential pressure within the combustion chamber and venting system. Specifically engineered as an OEM replacement part, the 100208408 ensures that the inducer blower is generating sufficient airflow to safely exhaust flue gases and support proper combustion. If the system detects a drop in pressure below the calibrated set point—often caused by venting obstructions, a failing blower motor, or restricted air intakes—the switch interrupts the ignition sequence to prevent faulty combustion or hazardous CO buildup. This HVAC safety switch features a robust diaphragm and precise electrical contacts (Common, Normally Open, Normally Closed) to provide reliable feedback to the integrated control module. For technicians troubleshooting Lochinvar boiler error codes related to "APS Open" or "Air Pressure SW," this genuine component is the standard for restoring system sequence of operation and maintaining high-efficiency HVAC performance.
Key Benefits- Precise Differential Sensing: Accurately monitors negative pressure to ensure the inducer fan is operating within manufacturer specifications.
- System Safety Integration: Acts as a primary fail-safe, preventing gas valve energization if exhaust venting is compromised.
- OEM Compatibility: Guaranteed fit and function for specific Lochinvar and A.O. Smith models, eliminating the calibration risks associated with universal switches.
- Durable Construction: Built to withstand the thermal cycling and moisture levels common in high-efficiency condensing environments.
What causes a "Low Air" or "APS Open" fault code?
While a faulty 100208408 pressure switch can be the culprit, technicians should first inspect for blocked PVC intake/exhaust pipes, cracked silicone reference tubing, or debris in the inducer housing that prevents the switch from closing.
Can I use a universal pressure switch instead of the 100208408?
It is not recommended. This low air pressure switch is factory-calibrated to a specific "inches of water column" (WC) set point unique to the heat exchanger’s airflow requirements. Using an incorrect part can lead to nuisance tripping or unsafe operating conditions.
How do I test the 100208408 switch in the field?
With the blower running, use a manometer to verify the actual pressure reaching the switch and a multimeter to check for continuity across the contacts. If the pressure meets the set point but the switch remains open, a replacement is necessary.
This item is not eligible for free shipping.
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 Lochinvar & A.O. Smith 100208408 Pressure Switch is a critical safety component designed for high-efficiency boilers and water heaters. As a low air pressure switch, its primary function is to monitor the differential pressure within the combustion chamber and venting system. Specifically engineered as an OEM replacement part, the 100208408 ensures that the inducer blower is generating sufficient airflow to safely exhaust flue gases and support proper combustion. If the system detects a drop in pressure below the calibrated set point—often caused by venting obstructions, a failing blower motor, or restricted air intakes—the switch interrupts the ignition sequence to prevent faulty combustion or hazardous CO buildup. This HVAC safety switch features a robust diaphragm and precise electrical contacts (Common, Normally Open, Normally Closed) to provide reliable feedback to the integrated control module. For technicians troubleshooting Lochinvar boiler error codes related to "APS Open" or "Air Pressure SW," this genuine component is the standard for restoring system sequence of operation and maintaining high-efficiency HVAC performance.
Key Benefits- Precise Differential Sensing: Accurately monitors negative pressure to ensure the inducer fan is operating within manufacturer specifications.
- System Safety Integration: Acts as a primary fail-safe, preventing gas valve energization if exhaust venting is compromised.
- OEM Compatibility: Guaranteed fit and function for specific Lochinvar and A.O. Smith models, eliminating the calibration risks associated with universal switches.
- Durable Construction: Built to withstand the thermal cycling and moisture levels common in high-efficiency condensing environments.
What causes a "Low Air" or "APS Open" fault code?
While a faulty 100208408 pressure switch can be the culprit, technicians should first inspect for blocked PVC intake/exhaust pipes, cracked silicone reference tubing, or debris in the inducer housing that prevents the switch from closing.
Can I use a universal pressure switch instead of the 100208408?
It is not recommended. This low air pressure switch is factory-calibrated to a specific "inches of water column" (WC) set point unique to the heat exchanger’s airflow requirements. Using an incorrect part can lead to nuisance tripping or unsafe operating conditions.
How do I test the 100208408 switch in the field?
With the blower running, use a manometer to verify the actual pressure reaching the switch and a multimeter to check for continuity across the contacts. If the pressure meets the set point but the switch remains open, a replacement is necessary.
This item is not eligible for free shipping.
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.
