What term describes the amount of gases that pass through the venting system due to draft?

The term that describes the amount of gases passing through a venting system due to draft is referred to as "flow." In the context of chimney and venting systems, flow specifically relates to the movement of flue gases produced by combustion as they are drawn out of the appliance and expelled through the chimney. This flow is influenced by factors such as temperature differences, wind conditions, and the design of the venting system.

Understanding flow is crucial for ensuring proper ventilation and safety in heating systems. Adequate flow prevents the buildup of hazardous gases inside the home and ensures that appliances operate efficiently. It is commonly measured in terms of volume per unit of time (e.g., cubic feet per minute).

The other terms, while related to the movement of gases, do not capture the specific concept of the volume of gases passing through the venting system due to draft. "Exhaust" typically refers to the gases expelled from a system rather than the measurement of their movement. "Discharge" often implies the release of something, but not in the context of measuring ongoing flow. "Current" might refer to a flow in an electrical context or fluid dynamics but is not used to specify the flow of gases in venting systems.