Williams P323073 Pilot/Generator Assembly

The Williams P323073 Pilot/Generator Assembly is a direct OEM replacement component designed for liquid propane (LP) heating systems, specifically engineered for Monterey Top Vent and Forsaire Top Vent furnace models. As a veteran-grade millivolt ignition system part, this assembly integrates a precision-tapered pilot burner with an high-output ignitor and lead wire to ensure reliable flame rectification and safety circuit continuity. In these heating systems, the pilot flame must maintain a consistent 750mV output through the thermopile/generator to keep the gas valve held open; a failing assembly often results in the common contractor headache of a pilot that lights but won't stay lit once the knob is released. This Williams furnace pilot assembly is manufactured to withstand the high-heat cycles of Forsaire Counterflow and Magnum Top Vent units, providing a stable, blue "blowtorch" flame pattern that optimizes heat transfer to the generator tip.

Key Benefits

• Precise OEM Compatibility: Verified fit for Williams Propane (LP) models including 2509821, 3509821, and the 5008631 series.
• Consistent Millivolt Output: Designed to generate the critical voltage required to energize millivolt gas valves, preventing nuisance shutdowns.
• Industrial-Grade Build: Rugged construction resists carbon soot buildup and corrosion in high-demand HVACR environments.
• Optimized Ignition: Included ignitor and wire assembly provide immediate spark-to-pilot ignition, reducing fuel waste during the startup cycle.

Common Questions

How do I know if the P323073 assembly needs replacement versus just a cleaning?
If the pilot flame is "lazy" and yellow rather than a sharp blue, the pilot orifice may be obstructed. However, if you have a strong flame but the valve won't stay open, use a multimeter to check the thermopile millivolt output. If it's dropping below 400-500mV while under load, the generator is likely failing and the entire P323073 assembly should be swapped.

Is this part compatible with Natural Gas (NG) furnaces?
No. The P323073 is specifically configured for Liquid Propane (LP). Installing an LP pilot assembly on an NG system will lead to improper combustion and hazardous operating conditions.

Does this kit include the thermocouple or thermopile?
This is a comprehensive pilot/generator assembly that typically includes the burner, ignitor, and lead. Contractors should always verify if their specific furnace model requires a separate P043800 thermocouple for secondary safety circuits common in Monterey series units.

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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.