Nothing might appear more cozy on a winter day than a crackling fire, however if it is burning in a uncovered fireplace, the coziness might be mere look. Instead of supplying you with warm atmosphere, the fire probably is sucking the warm air out of the room and sending it through the chimney. Even when there is not a fire paradoxically making the room colder by burning, you can be losing heat to a poorly-sealed fireplace and fireplace.
Combustion and Radiant Heat
As a fire burns, it is combining oxygen with the materials at the logs to generate a variety of gases, such as mostly carbon dioxide. The fire entices the oxygen it requires combustion from the room, and that creates a stream of air toward the fireplace. The heat of combustion sends the waste gases up through the chimney, and the subsequent convection current draws even more air toward the fireplace. The gases rising through the chimney remove most of the heat the fire produces. The radiant warmth you feel in front of the fire is only a fraction of the wasted heat.
Heat Loss Through Convection
Any strategy for improving fireplace efficacy involves not only increasing the amount of radiant heat, but decreasing the convection current drawing atmosphere toward the fireplace. This is important because air from a sloping part of the house, or even from outside, typically replaces the atmosphere the fire consumes. The result lasts even when the fire is not burning — warm air rises through the chimney, and colder air replaces it. If the damper is in good shape, you can keep warm atmosphere in the room once the fire is not burning closing it. If the damper is worn and does not seal correctly, use an inflatable chimney plug.
Improving Fireplace Efficiency
When the fire is burning, you can’t do anything about the warmth your fireplace loses through the chimney, but you can raise the radiated heat with an electric compressor. You may not notice any difference, nevertheless, in the event the fireplace continues to draw warm air out of the room. One approach to minimize this heat loss is to keep the damper partially closed when the fireplace is hot, and another way is to put a glass barrier in front of the fireplace. Convection continues even when there’s a barrier, however. You can’t block the fire’s access to atmosphere completely, or it’s going to go out.
Fireplace Inserts and Retrofits
Installing a fireplace insert is a far more effective approach to minimize heat loss than simply placing a glass barrier in front of the fire. You can vent the insert so it draws air from outside rather than from the room, and because it is a closed system, an insert gets hotter and radiates more heat than an open fireplace. If you prefer the texture of an open fire, then you can retrofit your fireplace to boost its efficacy. A retrofit typically comprises a deeper firebox that radiates more heat and also has ports to draw air from outside.