Fireplace in his own house - the dream of any romance. Who among us has not wanted to be on a winter evening in a comfortable chair at his own fireside, to blissfully imbibe the whole body heat released live fire.
That's just the smoke that fills the room and does not want to go up the chimney, in this idyllic picture does not fit. Contact chimney draft - the title of this unpleasant phenomenon. Why it occurs and how to deal with it? For information about this, we have collected for you and provided in this article.
Also focused on ways to check the draft in the chimney and in detail the best solutions to problems with traction.
The content of the article:
- What is a reverse thrust?
- The causes of back draft
- Ways to check draft in the chimney
Solutions with traction problems
- Option # 1 - deflector and its variants
- Option # 2 - a special valve-gate
- Option # 3 - the stabilizer of the chimney operation
- Conclusions and useful videos on the topic
What is a reverse thrust?
Before we understand the causes of this phenomenon, it is necessary to understand the essence of what is happening. The heating device installed in the building, together with the exhaust chimney form design.
Air pressure outside the device and it is not identical. Due to this difference in pressure arises Rod - aerodynamic directed flue gas stream.
The safe and efficient operation of the heating device assumes that the combustion will be moved from the burning fuel fume collection paths.
Air mass in the flue have a lower density, thereby seeking and upwards. In their place, it enters cooler outside air. It is in this and should be a change of flows in an ideal.
Backdraft - is not only unpleasant, but also dangerous phenomenon, whose consequences can manifest deterioration in the health of people and pets
But sometimes there is a phenomenon called reverse thrust. In this case, the smoke resulting from the combustion of the fuel is not directed to the outside through the chimney and into the premises.
The emergence of reverse thrust - it's not just unpleasant, but also dangerous phenomenon. Penetration of the combustion products in the room to cause serious poisoning and carbon monoxide shall be deadly.
The first signs of failure when moving air masses can not only be smoke coming into the room, but quickly bloat glass window in the door of the furnace. First draft may simply be weak, but if you do not take action, over time it will reverse.
Sometimes there is another phenomenon associated with the movement of the smoke - the air flow at multiple time changes its direction to the opposite. So there is a tipping rod.
The causes of back draft
There are several reasons for the emergence of reverse thrust. The main of them can be considered as mistakes in the process of the design of the heating system. Perhaps at its construction rules for the application of building materials have been violated.
The problem of this kind does not occur if the chimney designed in compliance with existing standards: Rotating must be done at 90 °, and the outlet at an angle of 45 °. Particular attention should be paid to the shape of the cross section of the chimney.
The most suitable shape is a circle. If the structure will be present corners, swirls can occur impeding the evacuation of the gases.
Chimney sweep profession, as you can see, has not lost its relevance, and, with an increasing number of private cottages, even became more and more popular
If you compare a brick and metal chimneys, the draft in the past will always be lower quality. The problem is that the metal is heated rather quickly, but just as quickly and cools it. A cold air, as is known, is lowered.
For frequent are the following reasons why there is no draft in your chimney:
- Obstruction of the chimney. It may well be that it is simply clogged garbage or bloated as a result of long-term operation. Rapid sooty may occur in the event that the chimney is made of pipes of different diameters. Do it in any case impossible.
- Errors in the calculation. Incorrectly calculated cross section for the passage of smoke. Quite often, in the design of structures arise layperson disparities in size of the device elements, combustion chamber and chimney. Powerful oven, for example, can produce a greater volume of combustion products than is able to bring a narrow chimney. Therefore, you need to carefully carry calculations chimney.
- design errors. Height smoke exhaust system is insufficient for its efficient operation. Shallow length chimney may cause a lack of difference in pressure. The optimum height of the chimney pipe is five - seven meters.
- Narrowing the smoke channels. there are narrow and horizontal directions in the areas of waterways diversion smoke. In such places, soot accumulates particularly active, which prevents the free movement of smoke.
- Wind backwater. The chimney is located in the "wind backwater." Cause backwater may be, for example, a high building located next to the chimney.
- Improperly organized room ventilation. Lack ventilation device or illiterate its absence leads to the desired supply air volume. It is therefore important to pay special attention proper ventilation organization in a private house.
If the ridge of the roof situated above the level of the chimney, the tilting rod can occur when a strong wind.
Atmospheric indicators also should not be excluded from the number of reasons for the formation of reverse thrust. High humidity of outside air, as well as strong gusts of wind can cause the formation of smoke reverse movement.
The same phenomenon can be observed in the case where the air is colder at home than in the street. Due to the difference in pressure may occur a strong smell of burning.
To prevent poisoning should ventilate the area. At the same time it is at least slightly warmed. Upset wind thrust and is capable of forming a swirling air flow on the roof. This phenomenon contributes to the well head in the wrong direction with respect to the ridge.
During the construction of baths so necessary to arrange the furnace to the chimney was inside the room, because if you place it on the outside, in the pipe will be formed condensate
Installation location of the chimney, too, is important. For example, if we are talking about heating baths, this part of the structure can be placed in the interior of buildings.
Such a solution would better to warm up the room, ensuring that even in extreme cold decent traction. If a tube placed along the outer walls, heating takes longer, and condensation can form in the tube itself.
Ways to check draft in the chimney
The fact of the presence of reverse thrust can be detected even in the early stages of the problem, before the smoke will fill your home.
Let's start with the people's ways. You can tear off a piece of toilet paper and bring it to the heater. Toilet paper - thin enough material to respond well to the movement of air. See which way deviated sheet. If he hesitates the room side, the presence of reverse thrust.
Check rod can be different folk ways, including using a candle: the direction of the spark flame will tell you, and thrust vector
Exactly the same experiment can be performed using cigarette smoke. It looks more clearer. Cigarette smoke unmistakably point you in the direction of pull.
Quality of the thrust can be determined and watch the flames in the heating system. White blaze and roar of the chimney indicates excessive draft, too, which is also not good, because it leads to excessive fuel consumption. Good results is as follows: the flame has a golden-yellow color, burning occurs uniformly and stably.
Anemometer (vetrometr) - a popular device that is used by professionals who by virtue of their profession check cravings functioning chimney
To check the scientific methods, we need to arm themselves with the equipment. The most affordable for ordinary users of the device is an anemometer (vetrometr). The appearance of the device, the variety presented in the video, which is placed in the final part of this article.
Solutions with traction problems
As it turned out, the reasons for the emergence of reverse thrust may be different. Therefore, standard solutions do not exist. We must look for a setting that matches the problem in each case.
If you carve the path blocked by debris or soot, it would take clean the pipe. If properly designed the way, construction will have to completely disassemble and assemble again.
If the defect is in the slow evacuation of combustion products, there are several ways how to improve forward thrust in the chimney. There are devices that help to strengthen the process.
Option # 1 - deflector and its variants
In solving the problem of how to further increase the thrust of the chimney can help deflector. It is installed on top of the chimney. This device "draws the" smoke, which is in the chimney shaft, using for this purpose the wind.
Deflectors - is a number of devices having a common functional purpose: improving traction, preventing reverse motion of the fuel combustion products
On the deflector is assigned several functions:
- trunk channel protection from external contamination and precipitation;
- strengthening the draft in the chimney;
- quenching the sparks resulting from incomplete combustion.
The operation of this device is based on the laws of physics. As the gas moves through the tapered pipe, its flow is accelerated. The pressure that it exerts on the shaft wall is reduced. There is a low pressure area.
A deflector mounted on the chimney, creates this zone vacuum when the air passes through the inside of the tapered channel in its construction. Gases discharged direct in zone, located at the mouth of the chimney, and by traction, enhanced wind output from the tube.
Material for making the most sought deflectors are aluminum, stainless steel and galvanized, although there are also expensive items made of copper, corrosion resisting well
Even simple baffles can improve the efficiency of removal of smoke by 20%. The presence of such devices creates enormous advantages for the heating system, as promotes complete combustion and better heat transfer. Therefore, it is popular and in demand.
Typically, a deflector comprises two cylinders - upper and lower, and a branch pipe connected with the lower cylinder, the protective cover and brackets intended for the fixation parts.
The upper cylinder is optional device component. Model without it consists of the following elements:
- lower cylinder mounted on deducing the smoke pipe;
- Diffuser - element dissecans air flows;
- two cap - forward and reverse.
The most expensive deflectors are made from copper. A generally used to create them ceramics and plastics, stainless steel, aluminum and galvanized. Aluminum and steel products are considered to be the most popular.
Despite the common features deflectors are very different. They differ not only in their appearance, but also the device, as well as sensitivity to air currents.
It is difficult to manufacture, but very attractive spherical deflector looks very futuristic, although it is a remarkable functional device
Consider the following classic deflectors model:
- TsAGI ventilation;
- Grigorovitch device;
- spherical "Volper."
In addition to all the recognized classics, there are relatively new models that differ unusual design solutions. This rotating model of the product and "weathervane". At the heart of their work are all the same laws of physics, which have already been mentioned above.
You do not want to spend money on the purchase of the deflector? And it is not necessary - it is quite able to make their own hands, using the materials at hand. And how to do it correctly, we We considered here.
Option # 2 - a special valve-gate
If you have problems with the stove, check the position of the gate. Schieber - a valve, which is designed to adjust the traction. It is usually mounted on the first meter non-insulated flue tube. This valve allows operation of heating equipment as efficient as possible.
In this device a number of functions:
- after burning fuel with the help of tube overlap, which allows to keep for long term heat;
- as traction control gate is used to change the cross section of the chimney: the excess thrust, for example, smoke channel can be narrowed;
- at its participation can control the combustion quality.
The material for the manufacture of slide is usually stainless steel, whose thickness is 1 mm. Due to the polished surface of the product with the soot is easily removed.
The temperature which can withstand such a valve does not exceed 900 ° C. It is strong enough and has a low coefficient of thermal expansion.
Retractable flap must not completely cover the target chimney: 85% - this is the rate that provides standards of safety in the operation of heating appliances
Schieber is represented by two models:
- horizontal sliding plate, which is most often used in brick chimneys;
- Rotary slide valve or throttle valve.
Throttle call all the same plate, which is fixed to the rotary shaft, placed inside the chimney or pipe.
The contours of the rotary slide plate repeat section of the chimney, allowing it to almost completely cover the pipe when the heater does not work
In view of the simplicity of the design make damper for trumpet simple hands. This homemade operation will be no worse than the purchased product.
Option # 3 - the stabilizer of the chimney operation
The product with the name of the speaker is also called chopper. This is a mechanism that automatically submits and dispensed into the air chimney, allowing to optimize the operation of the heating system, without attracting her man. To avoid creating an overpressure breaker is equipped with a safety valve.
For the production of flue draft stabilizer stainless steel is used. The maximum temperature which can withstand this device is 500 ° C.
Mounted on the chimney draft stabilizer must be adjusted in accordance with the recommendations that you find in the manual of your boiler heating
The essence of the stabilizer is that it allows automatically adding cold air directly to the chimney. The temperature and velocity of gas movement within the pipe is reduced. This increases the efficiency of combustion of fuel without any change in the mode of operation of the heater.
Fits breaker, generally at a chimney pipe. At this distance from the heating appliance (boiler) should be at least 0.5 meters. Breaker must always be indoors.
Since its operation is based on a system of precisely balanced weights, the influence of natural factors on the operation of this device should be excluded.
Setting the stabilizer can be considered complete when its regulator will put a value minimum draft in accordance with the specifications in the operating instructions of your heating boiler. Should either establish the exact parameter or the division above recommended.
Further applications are listed devices to prevent back-draft chimney pipe can be lengthened, its maximum straightened. Twists and tight turns shaft increases cavitation during injection of gases outwards.
Conclusions and useful videos on the topic
If the problem with the thrust does not occur in smoke in all the rooms, it does not mean that it is not. It will help to identify the device, with a device which can be viewed by looking at this video here.
This product may save your life, time to pay attention to the problem, since the carbon monoxide, for example, has no color, no odor.
This video provides information on the appearance of the deflector TsAGI and its component parts. You can see how to build this device independently.
If you feel the strength for the self-production of the stabilizer rod, then this video is for you to become a real guide to action.
Any device that operates in your home should work properly and do not create in the course of operation of a threat to life and health of people. Heating in this sense, is no different from other useful devices. To make it work stable and efficient help deflector vane and a stabilizer.
You have a problem with the draft in the chimney, and you try to solve it on their own? You will find the answers after reading this article? Or do you still have unresolved issues that we have missed? Feel free to ask them in the comments section and we will try to clarify these points.