HOW THE FIREPLACE IS OPERATING?
It is very important to know how a fireplace works and how it is burning in practice.
Wood burning is the chemical reaction in which carbonaceous wood is combined with oxygen, releasing energy as well as carbon monoxide and carbon dioxide. A necessary condition for this reaction is to have a temperature. The greater is the burning, the more amounts of gases and monoxide ignite, resulting in higher yields.
In other words, it results in more combustion and more energy being recovered in space.
Therefore, this is the main reason that closed heaters have a very high performance in compared to open traditional fireplaces because combustion occurs at higher temperatures.