Table of contents:
- How to increase the draft in the chimney with your own hands
- Useful information about chimney draft
- Why does reverse thrust appear?
- Strength test
- Troubleshooting methods
- Special devices for regulation
- Troubleshoot problems yourself
- Selection of devices for regulation
- How to increase cravings with your own hands: homemade appliances
Video: How To Increase The Draft In The Chimney With Your Own Hands: Identifying A Defect, Ways To Eliminate It, Etc
How to increase the draft in the chimney with your own hands
The operation of heating devices depends on the draft in the chimney, as well as the safety of residents of houses with stove heating. Eliminating possible problems will help you feel comfortable and confident in your home. You can increase or adjust the pressure indicator with your own hands.
1 Useful information about chimney draft
1.1 What affects the value
- 1.1.1 Intra-house moments
- 1.1.2 External factors
- 1.1.3 Features of the chimney design
- 2 Why does reverse thrust appear
- 3 Strength test
4 Ways to troubleshoot
- 4.1 Pipe cleaning
- 4.2 Eliminating design faults
- 4.3 Arrangement of ventilation
- 4.4 Instrument installation
5 Special devices for regulation
5.0.1 Photo Gallery: Traction Control Devices
6 Trouble shooting
- 6.1 We clean the pipe with a brush
- 6.2 Video: we clean the pipe with improvised means
7 Selection of devices for regulation
7.1.1 Photo Gallery: Deflector Types
- 7.2 Rotary devices
- 7.3 Draft regulators
8 How you can increase your cravings with your own hands: homemade appliances
8.1 Drawings and diagrams
8.1.1 Photo gallery: ready-made traction instrument circuits
- 8.2 We stock up on materials and tools
- 8.3 Preliminary phase
8.4 Getting Started
8.4.1 Video: do-it-yourself TsAGI deflector
- 8.5 Installing the deflector
Useful information about chimney draft
All residents of suburban or private city houses are familiar with such a concept as chimney draft. Do they know the essence of this term?
If we deviate a little from dry scientific terminology, then thrust can be defined as a natural phenomenon in which air moves from one area to another, namely, from an air zone with increased pressure to a zone with reduced pressure. All this happens with the help of a ventilation device - a special channel in the chimney.
Using this aerodynamic process, mankind began to use fireplaces, stoves, boilers, heating their homes with different types of fuel - coal, wood, peat, etc.
With good draft, the stove ignites quickly and the room is filled with pleasant warmth
From a properly designed and built chimney and, accordingly, from a good draft depends:
- the quality of room heating;
- reduced fuel costs;
- safety of being in buildings with their own heating.
What affects the value
There are three groups of factors that must be taken into account when constructing and checking a chimney.
A number of factors, indoors, can significantly affect the presence / absence of traction and its strength:
- The material from which the building was erected.
- Average room temperature.
- The maximum amount of airspace in a dwelling.
- The number of people permanently inside the housing.
- The presence of internal sources that additionally consume oxygen (air heaters, heaters, stoves, etc.).
- Regularity of fresh air supply (ventilation, ventilation).
There are other factors that determine the draft of the chimney, and they are located outside the heated room. We are talking about ambient temperature, atmospheric pressure, humidity, wind direction. The phenomenon of changing temperatures throughout the day can also affect traction due to the movement of cold and warm layers of air.
Difficulties with cravings appear for various reasons, some may simply not be noticed. For example, problems with air outlet through a chimney can arise if the chimney is much lower than the ridge of a building or tall trees nearby.
Chimney design features
The draft can be different depending on the design characteristics of the chimney:
- the presence of insulation;
- location (internal / external);
- presence / absence of irregularities or roughness, etc.
It is necessary and possible to control traction in a room using the "levers" of the first and third factors (in-house and design). Natural changes, naturally, do not depend on a person.
Keeping the chimney draft under control is a prerequisite for safe and comfortable living in your own premises. If the draft is very weak, then it is almost impossible to light the stove and heat the home.
In reverse thrust, combustion gases are “thrown” into the living space, and not into the air through the chimney. It is very dangerous for human health and life!
It is impossible not to notice such atypical behavior of smoke
With a very strong draft, all the heat is rapidly drawn out through the channels of the chimney, without having time to warm up the heated room to the required temperature.
Why does reverse thrust appear?
Weak thrust can be the basis for back thrust formation. How can you tell if you're not doing well with your cravings?
This is "said" by moments that can be ascertained with the naked eye: a lot of smoke in the stove, soot on the door, the incoming movement of smoke inside the house. In other words, smoke, fumes from the combustible fuel does not go into the chimney through the chimney, but tends to get into the living room with the door open and through the cracks.
Reasons for reverse thrust:
- Chimney design flaws. Low pipe - increased risk of back draft. The higher the chimney, the better the process of extracting exhaust gases and smoke goes. The optimum pipe height is about five meters.
- Correspondence of the pipe diameter to the parameters of the furnace device. A powerful stove requires a chimney with a rather large pipe. But here a measure is very important, since the use of a pipe that is too wide will make the combustion process unprofitable (all the warm air will literally fly into the pipe). It is unacceptable to use several pipes with different cross-sections in the chimney!
- Use of non-smooth pipes. Irregularities, chips, roughness, etc. are an obstacle to good traction. Over time, the chimney opening can narrow due to soot deposits and other combustion elements and hinder the process of kindling the stove and its normal functioning.
- Violation / lack of ventilation. Drafts, open windows in rooms above the firebox do not help the fuel combustion process, but distort it, making it useless and unsafe.
The chimney channels, made of metal, are in many ways inferior to brick pipes. Rapid heating and the same rapid cooling do not benefit the heating system as a whole and the chimney in particular.
Brick pipes are much more efficient at extracting smoke
Reverse thrust can also appear for objective reasons beyond the control of a person. Strong gusts of wind, rainy, cloudy weather with high humidity are unfavorable moments in terms of the formation of problems with traction.
There is such a term as temporary reverse thrust. What is it? In this case, it is worth talking about temporary traction violations, for several days. After a certain period, cravings return to normal.
Temporary backdraft can occur due to a cold room that has not been heated for a long time. The very cold air that has accumulated in the chimney tube interferes with the rapid combustion of the fuel. Therefore, smoke can be “pushed out” of the chimney into a dwelling, bathhouse or other room with a stove or fireplace.
It is very easy to eliminate cold air in the chimney - warm up the pipes by burning ordinary newspapers, wallpaper, paper in the oven. The main thing is that these materials are well dried.
If traction problems can be fixed continuously or at regular intervals, then it is necessary to take measures to eliminate the bad traction.
Before throwing your energy into a bad deadlift, make sure the deadlift really leaves a lot to be desired.
You can check the traction using special devices or yourself. Simple ways to fix the thrust:
- Light a piece of paper, let it burn a little. Bringing it to the stove or fireplace, put out the paper and observe the direction of the smoke. If it goes to the pipe - good traction, deviates in the opposite direction - reverse thrust, if it maintains "straightness" - there is no thrust. Similar manipulations can be done with thin tissue or toilet paper without setting it on fire.
- If there are smokers in the house, then observe the direction from the smoke of cigarettes or from the flame of a match, lighter near the fireplace or stove. Draw your conclusions in the same way as in the first point.
- The flame of an ordinary candle can also help in determining the draft in the home.
- A pocket mirror, brought to the firebox and covered with condensation, may indicate problems with removing smoke from the stove.
- The presence of too much draft, which carries away the useful heat from the room, is evidenced by an audible hum in the stove - a loud hum.
- The color of the fire in the firebox can be an indicator of different draft. Gold tint - good traction, white flame - excessive traction, red color and black smoke - poor traction, high probability of reverse thrust.
A regular lighter can help check traction
The anemometer is a device familiar to many people of the Soviet period. With this device it was possible to measure the draft of the chimney. Readings in the range of 10–20 Pa were considered normal. The disadvantages of the device are its low accuracy when the wind force is less than one meter per second.
Such a simple device will help to secure your life in a house with stove heating.
Modern industry offers a sufficient number of devices for measuring the draft, there are devices that fix the draft at the inlet and outlet of the chimney.
If you have identified problems with traction, then, of course, they need to be eliminated as soon as possible.
The choice of means to combat bad or reverse draft depends on the reasons that led to the abnormal operation of the chimney.
One of the common methods for improving traction is pipe cleaning. Fuel, burning in the stove, releases various substances that settle on the inner surface of the chimney. Soot adheres well to pipes if they are uneven or bent.
When carrying out work, do not forget about safety measures
How to clean the chimney to get good draft?
First of all, acting purely mechanically. The chimney channels can be made wider, getting rid of plaque, in the following ways:
- After preparing about one bucket of potatoes, peel and chop. Potato peelings are also suitable. Throw a little into the firebox and wait. When burned, potatoes will release starch, which will become a means that can soften carbon deposits. Soft pieces of soot will fall off on their own, while those that are firmly adhered will have to be removed mechanically.
- Aspen firewood. Heat the oven with two or three logs. They will very much heat up the chimney pipes and help get rid of carbon deposits. But this method requires special care, since the likelihood of a fire will be very high (soot can catch fire).
- Rock salt. This method is more suitable for prevention. The salt added at the time of burning improves the condition of the chimneys.
- Pipe brush. A heavy load is attached to a brush suspended from a steel rope and lowered into the chimney holes. By lowering and raising this structure, it is possible to force soot formations to fly off the walls of the pipes and fall into the furnace. These fragments are then removed from the firebox.
The second group of anti-soot measures is based on the use of chemicals. The most demanded chemicals for chimney cleaning are "Log-chimney sweep", "Kominichek". Chemical agents are added to the coals formed during the heating of a stove or fireplace according to the instructions and continue to heat. After all the fuel has burned out, it is advisable to leave the coals, since they continue to "work" in terms of cleaning the chimney (at least, this is what the manufacturers advise).
When used correctly, chemicals won't harm your home
Do not trust spiteful critics who talk about the obligatory ignition of soot when using the chemical method. This method does not pose any danger, since the beneficial effect is due to chemical reactions, and not due to the ultra-high combustion temperatures of the reagent.
It should be especially said about the observance of safety measures when carrying out all work related to the chimney. Do not fix chimney problems in windy weather! Try to use fall arrest devices when working at height!
Elimination of structural problems
When identifying certain features of the chimney design that negatively affect the thrust force, adjustments should be made to eliminate them. These actions include:
- dismantling several scattered pipes and installing a single chimney channel;
- roof chimney superstructure to the required height;
- insulation of chimney elements, etc.
In some cases, cravings can improve by avoiding drafts in the house or bath. You can help with problems with traction by installing ventilation devices on the windows.
In the absence of the desired effect after all the above methods, modern devices should be adopted to improve the draft in the chimney.
Installation of devices
To improve the operation of the chimney, it is best to use special devices that allow you to adjust and control the draft. Such devices can be bought in a store or made by hand.
Special devices for regulation
Modern instrument makers have taken care of the release of special devices that regulate the draft in the chimney:
- Regulators. They are installed on the chimney outlet to normalize the draft in the heating system, as well as as a means of influencing the heating efficiency.
- Deflectors. Such devices are fixed on the chimney from the outside. An improvement in the draft speed is carried out due to the fact that the diameter of this device is much larger than the chimney pipe, and, therefore, a low pressure area arises in it when air flows around it.
- Chimney weather vane. It is a special design that performs several functions at once: improves traction, protects the pipe from raindrops and snow whirlwinds. The operation of the device is similar to the operation of the deflector, the thrust speed is normalized by reducing the external air resistance.
- Smoke fan. It is very popular among owners of houses with a heating system. An artificial air vortex is created inside the chimney due to the operation of the ventilation system, which requires electricity to connect. Compliance with all necessary safety measures is a prerequisite for the installation and operation of such a device to improve chimney draft.
All devices installed on the chimney pipe to improve draft require mandatory control, especially in winter. This is due to the fact that additional devices attached to the chimney from the outside can become clogged, icy (in winter) and thereby prevent the normal operation of the chimney. Blockage caused by “assisted” devices can cause backdraft and carbon monoxide penetration into living quarters.
Do not forget to regularly inspect along with the chimney and appliances that help increase draft
Photo gallery: traction control devices
The most common device among stove heating users
Such a device is especially relevant for improving the operation of stoves and fireplaces.
A useful and beautiful device
By installing such a device, you can improve the performance of the entire heating system.
Troubleshoot problems yourself
Let's try with our own hands to make the heating process safe and efficient. The most common way to combat soot build-up in pipes is with a sinker brush.
We clean the pipe with a brush
First, let's prepare everything you need:
- Hard bristle brush. The diameter of this device is selected taking into account the section of the pipe (from fifty to three hundred millimeters).
- Thin metal cable (can be replaced with a very strong rope or rope).
- Weight for hanging from the brush.
This is what the chimney pipe cleaning device looks like
Do not start work if there is strong wind or too much humidity outside. Try to think over and use reliable insurance to protect yourself from unforeseen events.
The ruff is weighted with a sinker, attaching it to the bottom of the device. The brush itself is hung on a cable. All fasteners must be especially reliable, otherwise the structure will disintegrate and you will have to perform additional actions - to "fish" them out of the pipe.
First, they clean all the revision holes of the chimney, and then proceed to cleaning the pipe itself. By moving up and down a few times, you can get rid of the soot that will fall from the pipe into the oven. It is best if someone else is around the stove to signal efficiency and when to shut down.
Pipe cleaning should be completed when the soot stops pouring
You can also clean the pipe with the help of improvised means, as many videos have been filmed about.
Video: we clean the pipe with improvised means
Selection of devices for regulation
Let's consider some of the characteristic features and methods of using instruments for traction control and adjustment.
Such structures are installed on the chimney (at its very top) to create obstacles to air flows. The intensity of the wind force drops noticeably when meeting with such devices placed on the pipe. The smoke comes out through the channel "at will" due to the ingress of weak air flows into the pipe. These streams "catch" the exhaust gases and "push" them out.
Deflectors eliminate the possibility of pipe clogging, as well as tasteful, significantly improve the appearance of the entire building.
There are several types of deflectors:
- round Volperta;
- in the form of a plate;
- in the form of the letter H;
Almost all these devices are made of stainless steel, in rare situations - of copper. Using brackets, clamps, bolts, sealing tape, the deflector is attached to the chimney pipe. Some devices are also equipped with additional functions: for extinguishing sparks (to eliminate a possible ignition of the roof), for controlling the temperature of the outgoing air (in this case, the sensor is triggered if hot air does not come out and there is a possibility of reverse draft).
The disadvantages of using deflectors are their minimal efficiency in calm weather.
Photo gallery: types of deflectors
The most common traction device
Such a device can be purchased at specialized stores.
The choice of the device depends on the design features of the pipes and your preferences.
The turbines installed in the chimney head use the energy potential of the wind. The air currents set in motion a rotary nozzle (it always moves in one direction), and thus the air is rarefied near the chimney. It is completely excluded from entering the chimney with a rotary tube of any foreign objects and precipitation.
Rotary tubes have a big disadvantage, similar to the work of a deflector. Their use on a windless day is ineffective.
If you do not have great abilities, buying such devices is not a problem.
Such devices are a real find for residents of country houses, lovers of baths and fireplace gatherings. These devices are attached to the boiler chimney. They are equipped with a metal plate with a weight that balances it on one side. When the draft is good, the metal plate does not impede the free access of air into the chimney. With weak or reverse thrust, the metal plate serves as a kind of stupor.
The range limits for the thrust are set by the consumer himself, the usual parameters are 10–35 Pa.
The device works completely autonomously, it does not need an electric current supply.
How to increase cravings with your own hands: homemade appliances
Before you start building a deflector yourself, weigh your strength, review the available materials and only then get down to business.
Drawings and diagrams
To create a deflector with your own hands, you must use diagrams and drawings. You can use ready-made ones, presented in large quantities on the Internet, or you can do it yourself, relying on the data of ready-made diagrams and drawings.
Photo gallery: ready-made traction instrument circuits
On the Internet, you can find a good help for the construction of the device
Carefully study the instrument diagrams and choose the one that suits you
The diagram shows the device for improving traction
The diagram shows the components of this device
If you decide to test yourself and at the same time save money, arm yourself with measuring instruments to determine the inner diameter of the chimney. Depending on this value, you can, focusing on the table, determine the required parameters for the height of the deflector and the width of the diffuser.
With an inner diameter of 120 mm, these parameters are respectively 144/240, for a diameter of 140 mm - 168/280; if the internal section is 200, then 240/400; for a section of 400 mm, a deflector height of -480 mm is required, and a diffuser width of 800 mm.
You can calculate the necessary parameters (for a specific pipe diameter) yourself, using simple calculations. To determine the width of the diffuser, the inner pipe diameter must be multiplied by 1.2; the width of the umbrella for protection is considered to be -1.7 x d; We find out the total height of the structure if we multiply the size of the inner section by 1.7.
Having received all the dimensions, we build drawings for more accurate cutting. We draw diagrams on a sheet of Whatman paper or on the back of the remaining pieces of wallpaper.
It is best to build a full-size drawing. So that during cutting it is easy to attach the cut paper parts to the steel sheet and not to recalculate the data taking into account the scale of the drawing.
We stock up on materials and tools
Everything must be prepared in advance so as not to be distracted during work.
We need to make a deflector:
- galvanized sheet with a thickness of at least half a millimeter, you can use stainless steel;
- scissors for metal;
- drill with different drills;
- riveting device;
- a hammer;
- clamps, nuts, bolts;
- marker (for transferring the drawing to a metal sheet).
The preparatory work consists not only in drawing the details of the device, but also in cutting them out and trying them on. All paper elements are fastened with paper clips or a stapler and applied to each other. If all goes well, you can carefully remove the bartacks and straighten the templates.
Do not be negligent in the process of creating a deflector, try to think about your safety. In order not to injure your hands and to protect your eyes, use the gloves and special glasses prepared in advance.
So, everything is in place, you can start!
A step-by-step description of the sequence of actions will help you:
- We transfer the parts cut out of paper to a galvanized sheet. We should have a sweep of the following elements: a cap, a diffuser, an outer cylinder and a rack.
- Using scissors for metal, carefully cut out all the components of the deflector. In places of cuts, the metal is bent with pliers to a half-millimeter thickness and "passed" with a hammer.
- The blanks of the diffuser, cap and cylinder are rolled up and drilled holes for fasteners (if bolts are used). Connections are made using rivets or bolts; in exceptional cases, welding (semi-automatic) can be used.
- To fix the cap, we prepare 3-4 metal strips. The dimensions of the strips are 6 by 20 cm. The strips bent at the edges and knocked out with a hammer must be bent in the shape of the letter P. Drill 3-4 holes on the cap, five centimeters from the edge, and fasten the metal strips with bolts.
- The other ends of the galvanized strips must be attached to the diffuser, thereby "looping" the hood and diffuser.
- We insert the resulting structure into the shell.
You can watch the video about the construction of the TsAGI deflector with your own hands.
Video: do-it-yourself TsAGI deflector
The first way is to climb onto the roof and, observing safety precautions, attach the made device to the chimney pipe.
You can make your work a little easier - attach the deflector to an additional pipe, which is then raised to the roof and inserted into the main pipe.
We put the homemade device in place in a second, safer and more convenient way. We need a piece of pipe with a slightly larger diameter than that of the chimney. Having departed from the edge of the cut pipe about fifteen centimeters, mark and make holes, perform the same manipulations on the wide part of the diffuser.
We fix the pipe and diffuser using pins inserted into the holes. We screw on the nuts on both sides - from the pipe and diffuser side and tighten them. When working, we make sure that there are no distortions and damage.
Using a clamp, we tighten the structure with a deflector on the chimney pipe. Try to do this so that no gaps or gaps appear.
Large buildings also need traction control devices
The process of self-adjustment of draft is necessary in order to comfortably and safely live and relax in a house with stove heating. To do this, you can use different methods that are suitable for your chimney design: pipe cleaning with a brush, "chemical cleaning furnace", installation of special devices. Traction control devices can be purchased or made yourself.