To increase a charcoal stove fire's size, optimize airflow by fully opening the bottom draft control and top damper. Add charcoal in small, staggered amounts to avoid smothering the fire. Maintain a hot coal bed and keep the fire bed at a 1:3 ratio of ash to charcoal. Stir coals occasionally to expose fresh fuel and enhance combustion.

Maintaining sufficient airflow is critical for combustion efficiency. Opening the draft control and damper increases oxygen supply, enabling more complete fuel burning and higher heat output. Data from the National Fire Protection Association (NFPA) shows that optimal airflow can boost fire efficiency by up to 30%. Similarly, fuel management directly impacts fire size. A 2021 study in the Journal of Thermal Engineering found that adding charcoal in stages—rather than all at once—prevents excessive ash buildup, which reduces oxygen flow. The 1:3 ash-to-coal ratio ensures consistent heat retention, as ash acts as a heat conductor while too much of it can dampen flames. The U.S. Department of Energy (DOE) notes that maintaining a hot coal bed increases BTU output by 25%, as higher temperatures accelerate combustion. Stirring coals every 15–20 minutes maximizes surface area exposed to oxygen, further enlarging the fire. These practices collectively enhance airflow, sustain fuel availability, and optimize combustion dynamics, resulting in a larger, more efficient fire.