Lochinvar & A.O. Smith 100109834 Gas Valve

The 100109834 Gas Valve is a direct replacement service part engineered for high-performance Lochinvar Knight and A.O. Smith high-efficiency boilers. This combination gas control valve is configured for Natural Gas applications, featuring a 1/2" NPT inlet/outlet and a standard 24V AC solenoid operator. Designed to maintain stable manifold pressure, it operates at a 3.5" W.C. regulation setpoint. Reliable ignition and consistent BTU output depend on this valve's precise diaphragm response and internal regulation. When troubleshooting ignition failure or erratic flame rectification on Lochinvar KBN or A.O. Smith commercial water heaters, verifying the gas valve manifold pressure is a critical diagnostic step. This negative pressure regulated valve integrates seamlessly with existing wire harnesses and burner assemblies, ensuring the combustion system meets OEM specifications for air-fuel ratios. Replace the 100109834 when the internal coil fails or the valve body exhibits mechanical fatigue to ensure system safety and efficiency.

• Precise Pressure Regulation: Factory-calibrated to 3.5" W.C. Natural Gas to ensure optimal combustion efficiency.
• OEM Compatibility: Exact replacement for 100109834, VAL30034, and 100109833 part numbers.
• Standardized Connections: Features 1/2 inch NPT threading for compatibility with standard rigid pipe or flex connectors.
• Reliable 24V Logic: Designed to interface directly with integrated boiler control boards for safe sequencing.

Common Questions:

How do I test the 100109834 gas valve coil? Use a multimeter to check for 24V AC at the terminals during the ignition trial. If voltage is present but the valve fails to open, the solenoid is defective.

Can this valve be converted to Propane (LP)? Most 100109834 valves require a specific LP conversion kit or an OEM-specified spring change; always verify the current orifice and spring rating before adjustment.

What are the symptoms of a failing Lochinvar gas valve? Typical indicators include intermittent error codes (ignition lockout), delayed ignition, or the inability to reach target manifold pressure under high-fire conditions.

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.