Lochinvar & A.O. Smith 100262938 Gas Valve

The Lochinvar & A.O. Smith 100262938 Gas Valve is a critical OEM replacement part engineered for high-performance water heaters and boilers. This 1-inch Natural Gas (NG) control valve is a direct replacement for Honeywell WV8840B1141, ensuring seamless mechanical and electrical integration without field modifications. Designed for standing pilot applications, the valve features an integrated NTC temperature sensor housed within an immersion well, providing precise thermal feedback to the control logic for stabilized water temperatures and safe combustion cycles.

Operating on a self-powered thermopile system, this 100262938 gas control functions independently of external 120V power, making it a reliable solution for residential and light commercial atmospheric vent models. The unit supports a regulation range of 30,000 to 85,000 BTUh and is rated for a maximum inlet pressure of 14.0 in. w.c. (0.5 PSI). Its 90-degree body configuration with a 1/2-inch NPT inlet and 1/2-inch inverted flare outlet facilitates standard manifold alignment. For professional contractors, this valve is the standard for restoring combustion safety and flame rectification in A.O. Smith and Lochinvar systems.

• Direct Hardware Correlation: Precisely matches WV8840B1141 specifications, ensuring exact fitment for A.O. Smith and Lochinvar storage-tank units.
• Self-Sustaining Operation: Utilizes millivolt power generated by the standing pilot (350–850 mV range), eliminating the need for external electrical wiring.
• Integrated Thermal Management: Features a built-in immersion sensor for accurate setpoint maintenance and high-limit (ECO) safety shutoff.
• Standardized Porting: 1/2-inch inverted flare outlet provides a secure, leak-resistant connection to the main burner and pilot assembly.

Is the 100262938 compatible with Liquid Propane (LP) systems?
No, this specific part number is calibrated strictly for Natural Gas (NG). Using this valve with LP will result in improper manifold pressure and hazardous combustion conditions.

Can the temperature sensor be replaced separately?
The NTC thermistor is integrated into the valve's immersion well components. If the sensor fails or provides inaccurate resistance readings, the entire gas control assembly must be replaced to maintain FVIR safety compliance.

What should I check if the pilot won't stay lit after installation?
Verify that the thermopile is generating at least 350 mV (open circuit) and that the status light is blinking. Ensure the pilot tube is clear and the combustion chamber has adequate airflow for a stable flame.

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.