There are some elements that can prevent a fireplace from drawing properly. It depends on this that the consumed fuel is optimal, that the smoke comes out where it should, and that the room where the fireplace is located is completely safe. The chimney maintenance is essential for proper draft. Although sometimes this may not be enough.
What is the draft of a chimney?
The draft of a chimney is the process by which combustion products, such as smoke, gases, and particles, are extracted from a building to the outside through the chimney. The draft is essential to maintain a safe and healthy environment inside a home, as it helps to prevent the accumulation of harmful gases, such as carbon monoxide.
How to achieve a good draft in the chimney?
The draft is achieved by creating an air current that flows from the interior of the home to the chimney. This airflow occurs due to the difference in pressure and temperature between the hot and less dense air inside the chimney and the colder and denser air outside.
As the hot air from the fireplace rises, it creates a suction effect that attracts fresh air from the outside into the interior of the house through ventilation openings and cracks, thus feeding the fire and maintaining the airflow that extracts smoke and combustion gases to the outside.
How to tell if my chimney isn’t drawing properly?
How can we tell if our chimney is drawing properly? There are several ways to determine this, some more complex than others.
Using a depressiometer
There is a device that measures the depression produced by the chimney to determine if it is at adequate levels. This device is called a depressiometer, and if the test result indicates that the depression is within the recommended level by the chimney manufacturer, everything is fine. Otherwise, it would be necessary to investigate the reasons why the depression is higher or lower than it should be.
Some chimneys have a built-in depressiometer, although it may happen that we don’t have one. In that case, we will have to check it using other methods.
If we don’t have a depressiometer, we can observe how the smoke and fire behave when we light our fireplace. If we see swirls or if smoke enters the room when we open the door, it means that it is not drawing well and that we need to clean the chimney inside to remove any accumulations that block the smoke outlet. If it is clean, the chimney’s exhaust needs to be higher.
If the fire tends to rise too much and in a pointed shape when lit, the problem is the opposite. The draw is excessively strong, and it is necessary to control the air inlets to reduce it. If we don’t do so, we will consume much more fuel than usual and won’t achieve the comfort that a properly drawing chimney provides. It can also lead to condensation and moisture problems inside the house.
How to deal with poor chimney draft
If you notice that the chimney has too much draft or doesn’t draw well, you can use some available elements, such as air intakes or the so-called damper, a component that can be opened or closed depending on the need for air. If you have one of our fireplace doors installed, you can easily adjust the air intake with a simple turn of the damper handle.
You also have the option to install a damper regulator to adjust the draft according to the weather conditions, as the outside temperature also affects how the chimney draft works. Atmospheric pressure can either facilitate the smoke exhaust or cause it to stay inside and accumulate.
If the problem persists, it may be necessary to add more flue pipe to increase the draft. This often happens in modern homes because they are more airtight and allow less air in compared to older houses due to the insulation used nowadays.