What is one way to increase draft through a natural draft furnace?

Increasing the temperature of the stack enhances the draft in a natural draft furnace because warmer air is less dense than cooler air. As the temperature of the stack increases, the hot air rises more rapidly, creating a stronger upward flow that enhances the draft. This process relies on the principle of buoyancy; as the hot air moves up and out of the stack, it creates a vacuum that draws in cooler air from outside to replace it. This continuous movement of air is essential for the efficient operation of a natural draft system, ensuring that combustion gases are effectively evacuated and fresh air is supplied for efficient burning.