What is the minimum vertical height a type B-W gas vent must terminate above the bottom of a wall furnace?

The minimum vertical height a type B-W gas vent must terminate above the bottom of a wall furnace is 12 feet. This requirement is in place to ensure proper venting and safe operation of the gas appliance. The vertical height helps in creating the necessary draft for the venting system, which is crucial for the efficient removal of combustion gases.

Having the vent terminate at this height helps to reduce the chances of flue gas re-entering the living space and minimizes the potential for backdrafts, which can lead to dangerous situations. Additionally, the specified height contributes to the vent's effectiveness in overcoming the pressure differences that may exist within the building, allowing for the safe and controlled expulsion of exhaust gases.

This regulation aligns with safety and performance standards established in the National Fuel Gas Code and ensures that a safe environment is maintained around gas-fueled appliances.