Lochinvar & A.O. Smith 100109841 Gas Valve

The Lochinvar & A.O. Smith 100109841 Gas Valve is a direct replacement component engineered for high-efficiency commercial and residential water heating systems. This replacement gas valve operates on a 24V signal and is factory-calibrated for Natural Gas applications with a 3.5" W.C. manifold pressure setting. Featuring 1/2" NPT inlet and outlet ports, this Robertshaw gas valve assembly ensures precise fuel metering and reliable ignition cycles within high-recovery systems. The integrated solenoid design facilitates rapid response times for modulation or on/off firing sequences, maintaining optimal combustion stability. This HVAC gas valve is critical for restoring system performance in Lochinvar Knight and A.O. Smith Cyclone models. When installing the 100109841 gas valve, technicians should perform a combustion analysis to verify CO2 levels and gas pressure alignment with the manufacturer’s data plate to ensure long-term operational efficiency and safety.

• Precise Fuel Regulation: Factory-set at 3.5" water column to maintain consistent thermal output and burner efficiency.
• Direct Fit Compatibility: Specifically designed for A.O. Smith gas water heaters and Lochinvar boilers, reducing troubleshooting and field modification time.
• Reduced Pressure Drop: Optimized internal flow paths through the 1/2" NPT connections ensure sufficient gas volume during high-fire demands.
• Rugged Solenoid Construction: Built to withstand the high-cycle demands of commercial applications without losing seat integrity.

How do you verify if the 100109841 gas valve is receiving power?
Using a multimeter, check for 24VAC across the solenoid terminals during the ignition sequence. If voltage is present but the valve fails to open, the internal operator or coil has failed.

Can this valve be converted to Liquid Propane (LP)?
This specific model is calibrated for Natural Gas. Converting these valves typically requires a manufacturer-approved conversion kit to change the spring and orifice settings to maintain safe combustion parameters.

What are the symptoms of a failing gas valve in a Lochinvar boiler?
Common indicators include ignition lockout codes, unstable flame signals, or the inability to reach target manifold pressure during the high-fire stage of the startup sequence.

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.