Lochinvar & A.O. Smith 100208398 Pressure Switch

The Lochinvar & A.O. Smith 100208398 Pressure Switch is a critical OEM safety component engineered for high-efficiency boilers and commercial water heaters. Calibrated to a precise 7.05" WC (Water Column) trip point, this switch ensures the combustion blower is generating the necessary static pressure to safely vent flue gases before the ignition sequence begins. It serves as a direct, drop-in replacement for legacy part numbers PRS2432 and PRS2432K, maintaining the factory-specified pressure differentials required for optimal burner performance.

Designed for the rigors of mechanical rooms, this 7.05 Inch Water Column switch features robust diaphragm construction and silver-plated contacts to prevent signal drift or nuisance lockouts. Whether you are servicing a Lochinvar Knight series or an A.O. Smith standard-power vent model, this genuine 100208398 HVAC part provides the exact electrical switching logic needed to satisfy the control board's safety loop. Integrating this OEM boiler pressure switch into your maintenance routine prevents intermittent "Pressure Switch Failed to Close" error codes and protects the heat exchanger from poor combustion conditions.

• Precise 7.05" WC Calibration: Specifically tuned for high-static venting requirements to ensure accurate flue gas monitoring.
• Universal Compatibility: Fully replaces 100208398, PRS2432, and PRS2432K for seamless inventory management.
• Enhanced Duty Cycle: Built with high-grade materials to withstand the rapid cycling and thermal fluctuations typical of commercial boiler applications.
• OEM Integrity: Guarantees the same electrical ratings and physical mounting footprint as the original factory-installed component.

Common Questions

What causes a pressure switch error on Lochinvar or A.O. Smith units?
An error typically indicates the switch is not detecting its rated 7.05" WC. Before replacing the part, technicians should check for a blocked vent terminal, a failing inducer motor, or moisture in the sensing tubes.

Can I use a pressure switch with a different WC rating?
No. Using a switch with a different Water Column rating will compromise combustion safety and lead to premature ignition failure or unsafe CO levels. Always match the OEM specification of 7.05" WC for these specific models.

Is this switch compatible with PRS2432K?
Yes, the 100208398 is the current technical successor and is identical in function and form to the older PRS2432K and PRS2432 part numbers.

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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.