BW vent shall be used only with an approved:

In the context of venting systems, the BW vent is specifically designed for use with certain types of appliances that have particular venting requirements. The correct option relates to the operational characteristics of a recessed wall furnace. This type of furnace is typically installed in a wall space and requires a specific venting arrangement to ensure proper operation and safety.

Recessed wall furnaces are designed to exhaust combustion gases in a controlled manner, directly affecting their efficiency and safety. The BW vent system is compatible with such appliances as it fits their regulatory and performance needs, ensuring that combustion gases can be safely and effectively vented out of the living space.

Understanding the venting requirements of various appliances is crucial, as improper venting can lead to dangerous situations, such as backdrafting or the accumulation of harmful gases indoors. Therefore, using a BW vent with approved appliances like recessed wall furnaces is vital for maintaining safety standards.