Lochinvar & A.O. Smith 100208387 Pressure Switch

The Lochinvar & A.O. Smith 100208387 Pressure Switch is a critical safety component calibrated to a 1.15" WC setpoint for commercial and residential water heating systems. This SPST (Single Pole Single Throw) air pressure switch is designed to monitor vent pressure and ensure the inducer motor is moving sufficient combustion air before allowing the ignition sequence to proceed. As a direct replacement for the Lochinvar PRS20031 and 100166126, this genuine OEM replacement part ensures the control board receives the precise signal needed to maintain safe operation and prevent error codes like the common 3-flash sequence associated with pressure circuit failures.

For technicians servicing Lochinvar boilers or A.O. Smith power vent water heaters, maintaining exact pressure switch specifications is vital to avoid nuisance shutdowns. This switch is engineered for high-cycle reliability in demanding HVACR environments. Its 1.15-inch water column threshold is factory-set to meet the specific static pressure requirements of compatible models, including the CBL, CBN, and CW series. Using this 100208387 air pressure switch preserves the integrity of the combustion system and ensures a seamless drop-in fit for rapid field repairs.

• Precise 1.15" WC Calibration: Ensures accurate sensing of air pressure and exhaust flow to satisfy safety interlocks.
• OEM Compatibility: Identical to PRS20031, providing a direct match for Lochinvar and A.O. Smith equipment.
• Enhanced System Safety: Prevents the combustion process if venting obstructions or inducer failures are detected.
• Durable SPST Contacts: Engineered for reliability over thousands of cycles in high-heat water heating applications.

• What does a 3-flash error code mean on my unit? This typically indicates the pressure switch is stuck open or closed. Verify the 100208387 is receiving the correct 1.15" WC signal using a digital manometer before replacing.
• Can I use a universal pressure switch instead? No. Lochinvar water heaters require the specific 1.15" WC rating of this switch to ensure the burner fires within safe manufacturer parameters.
• Is the PRS20031 interchangeable? Yes, the 100208387 is the current production part number and is technically identical to the legacy PRS20031.

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.