The draft in the chimney is a key moment in the functioning of heating structures and the fire safety of residents of houses with stoves. Eliminating possible malfunctions will improve the quality of the oven, which will make you feel confident and comfortable in your home. To do this, it is important to know why there is no draft in the stove, how to determine its level, as well as modern methods of regulating the output of combustion products.
Methods for measuring thrust
The main device for taking measurements in chimneys is an anemometer. It has been used until recently due to its ability to obtain accurate results with an average smoke flow rate of over 1 meter per second.
Now more accurate devices are used for measurements. They are used by professional chimney sweeps and allow you to determine why there is no draft in the oven at home.
Checking the draft in the chimney without using special devices is possible using thin paper. To do this, a piece of paper is placed in a tube and its vibrations are observed. Movements in different directions indicate the absence of violations in the removal of combustion products.
You can also use a lighted match. In addition to the direction of the flame, you need to evaluate its color:
- A yellowish golden hue is normal cravings.
- Dark red flashes indicate that the smoke is not being emitted.
- Flames with a pure white tint together with chimney noise indicate strong draft.
When firing up the stove, the smoke stream can be directed into the sauna or home room. This indicates the presence of reverse thrust. The heating system must not be started until the problem is solved, as it will smoke inside the room.
What causes poor traction?
Furnace draft depends on many factors. The main reasons for the violation of the output of combustion products through the chimney are:
- soot;
- violation of ventilation;
- environmental factors.
Soot is formed after the combustion of coal or wood. It is the end product of combustion that settles inside the heating system, which narrows its diameter and causes reverse draft.
To solve this problem, you need to carry out regular cleaning of the pipe. In order to prevent heavy contamination, use solid fuel briquettes from wood. They have lower indicators of moisture and harmful substances.
The lack of air in the building leads to the development of reverse draft. On the other hand, strong drafts are unfavorable for the normal functioning of the heating system.
Before firing up for the first time, check the air movement in the building. This will eliminate the likelihood of poisoning by combustion products.
High humidity and strong winds are the main environmental factors in which smoke is not evacuated. High levels of air humidity are formed at a reduced level of atmospheric pressure. This discharges smoke and disrupts gas flows.
Strong winds will prevent the smoke from escaping properly. Reverse thrust may develop during gas flow changes. This applies to chimneys that are connected to the firebox and do not have heating wells.
Wind protection is provided by pipe caps. They also prevent the pipe from getting wet when it rains and snows.
Regulation methods
Setting the draft to a normal level ensures high efficiency of the heating structure at home or in a bath. It also increases fire safety and prevents the likelihood of poisoning by combustion products. Several techniques are used for this:
- installation of the stabilizer;
- increase in pipe length;
- installation of rotary turbines.
Installing the stabilizer
The device is installed on the chimney. At the bottom of the device there is a special hole that provides unhindered circulation of gases to control the air level in the chimney.
Together with the stabilizer, a sensor is installed to monitor the temperature of the outgoing combustion products. The alarm system is triggered when the pipe is heated by gases during a decrease in thrust.
Increasing the length of the chimney
When using the method, you must follow a number of rules provided for the normal operation of the heating system.
- The chimney height is at least 5 meters. Optimally - more than 6 meters in a two-story building and an extension of 4 meters for each floor.
- The chimney is located above the ventilation duct. This will prevent carbon monoxide from entering the room.
- The height of the chimney section above the roof of the building is at least 50 centimeters.
- It is recommended to entrust the pipe section to a master who will do everything in accordance with the established standards. Otherwise, the draft may disappear, after which the stove will cease to perform its function.
When installing a chimney, it should be borne in mind that inclined and horizontal sections have a negative effect on gas flows. To solve the problem, you need to lengthen the chimney pipe.
Using a rotary tube
Turbines above the chimney heads enhance the processes of removing combustion products by discharging the smoke. In addition, the device protects the chimney from all kinds of debris and meteorological precipitation.
The role of the damper in the operation of the heating system
The gate, or damper, excludes the possibility of the development of reverse thrust and increases the fire safety of the room. It is installed by 2 methods:
- into the chimney;
- on the oven door.
The damper serves as a kind of regulator. When the gate is closed, the cross-sectional area of the pipe decreases together with the rod and vice versa.
Using the traction stabilizer
In order to maintain an optimal level of thrust, a secondary air supply device is used, which is called a chopper or stabilizer. Safety valves prevent pressure build-up in the chimney and oven.
This device is installed on the chimney. It has an iron plate with a weight on one side. With weak or reverse thrust, it serves as a kind of stupor and does not allow combustion products to get inside the room.
Standard pressure parameters are 10-35 Pa. The range of borders is set by the user. The device is completely autonomous and does not require power supply, which is very convenient in everyday use.
If there is no draft in the heating boiler, you should call a professional chimney sweep. He will assess the state of the structure, tell you why to install the devices, and give advice on how to use the device.
Ensuring normal draft is one of the main tasks when working with heating structures in houses and baths. It is not recommended to rely entirely on devices. It is necessary to independently control the operation of the oven and clean it in a timely manner. This will provide comfortable conditions during the use of the premises, as well as the stable functioning of the heating system and increase the fire safety of the building.
