What would be the approximate combustion air requirement for a system using natural gas as fuel?

The approximate combustion air requirement for a system using natural gas as fuel is typically around 15 cubic feet of air per 1,000 BTUs of gas burned. This figure is important as it helps ensure complete combustion, which is necessary for efficient energy use and to minimize the production of harmful byproducts such as carbon monoxide.

Natural gas has a specific requirement for oxygen to combust effectively. Sufficient air is crucial not only for the efficiency of combustion but also for the safety of the system. When there is inadequate air, it can lead to incomplete combustion, resulting in the release of pollutants and potentially hazardous conditions.

In the context of this question, the choice indicating 15 cubic feet aligns with the general industry standards for natural gas combustion, taking into account the required oxygen and ensuring optimal performance of the system.