Williams 9303 Extension 318973-401 This specific part number is

This specific part number is a complete assembly

A missing or damaged baffle can cause erratic flame signals or tripping of high-limit switches

it requires both a dedicated positive and negative trigger wire to the small terminals

7 Cv rating meet my system requirements

designed for high-risk areas where immediate detection is required to prevent catastrophic equipment failure

Williams 9303 Extension 318973-401 This specific part number isThe 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