Constructed with a Monel bellows for superior corrosion resistance and high-temperature durability

verify the 100208549 sensor resistance against the manufacturer’s temperature-to-resistance chart during troubleshooting

Engineered for 240V operation

this assembly supports field-selectable control signals

Engineered for atmospheric gas-fired boilers

Williams 9303 Extension 340155-7024 Constructed with a Monel bellowsThe Williams 9303 Extension is a professional grade 24 inch vent extension kit engineered specifically for direct vent gravity wall furnaces. This heavy duty galvanized steel vent extension is the standard solution for HVAC installers dealing with deep wall penetrations where standard venting falls short. It is designed for use with wall thicknesses ranging from 15 inches to 24 inches, ensuring a secure and code compliant flue path from the furnace to