What is one method to increase natural draft?

Installing a higher chimney is an effective method to increase natural draft. The principle behind this is based on the stack effect, where the height of the chimney impacts the temperature difference between the hot gases inside the chimney and the cooler air outside. A taller chimney enhances the natural draft by creating a stronger upward pull, as the buoyancy of the warm air rises more rapidly compared to cooler air. This allows for a more efficient venting of combustion gases, thereby improving the overall performance of the system.

While decreasing the amount of excess air, increasing primary airflow, and using a forced draft fan can influence airflow and combustion efficiency, they do not directly enhance the natural draft in the same way a taller chimney does. The natural draft relies primarily on the chimney's height and the temperature difference between the inside and outside air, making the height of the chimney a critical factor in optimizing natural draft systems.