Decoy
The lighting of a decoy is used in combustion technology or when heating a stove to restore the chimney effect in the chimney in such a way that the chimney effect in the chimney is restored so that the flue gases from a fireplace can pass through the chimney if there is temporarily no chimney draft due to the weather (for example in inversion weather conditions ) or at temperatures that are higher than inside Can pull off the chimney.
A dosed fire is lit either at the lowest point of the chimney, the cleaning opening, for example in the basement, or in the fireplace. Cold air should be heated in the chimney and rise to the top so that free convection can take place and the counter pressure of the heavier cold air can be overcome. If the chimney wall is colder than the outside air, the air column in the still unheated chimney has a greater density than the warm air. During the heating-up phase, it will flow downwards along the cold inside wall of the chimney, while the warm exhaust gas rises more in the middle of the chimney. Only after sufficient warm exhaust gas has risen and swirled is the smoke that can be extracted through the chimney for stoves, stoves and boilers thanks to the suction effect.
Not only when the building structure temperature is too low, when the outside temperature is higher at the same time, but also when there is residual moisture in the newly built masonry, a decoy may be necessary to set proper combustion in motion without smoke and exhaust gases flowing into the room, as humid air also has combustion channels can block.