Wolpert Grigorovich deflector simplified drawing pattern

The most common method of removing combustion gases (chimneys) and ventilation all over the world is natural draft, which arises due to the difference in temperature and pressure indoors and outdoors, but this is precisely the problem, since in summer the edges are erased. There can be two solutions here: creating forced traction using an electric motor with an impeller, or installing a Volpert-Grigorovich deflector or another model that you can assemble with your own hands (drawing attached). The latter option is beneficial in all respects - it is autonomous (does not depend on a connection to the ≈220 V network), does not require forced start and stop, does not require repairs (only preventive maintenance), and it can also be made from improvised means.

Each of these deflectors is designed to improve traction

Volpert Grigorovich deflector

This type of device is the most effective and popular.
Therefore, we will talk about it in more detail. This deflector is often installed on the chimneys of gas boilers. The key feature of this design is the presence of an inverted cone under the umbrella. Therefore, during side blowing, a reduced pressure occurs in the channel, and combustion products rush out of the flue.

In case of strong wind “from top to bottom”, the pressure in the deflector area can, on the contrary, increase. This point must be taken into account when designing and installing a smoke exhaust system. But in most cases, the airflow occurs from the side. Therefore, the type of product under consideration is suitable for most gas ducts.

They look like this:

• diffuser diameter: bottom - 2*D, top - 1.5*D;
• diffuser height - 1.5*D;
• immersion of the channel into the diffuser - 0.15*D;
• the height of both cones of the umbrella is 0.25*D;
• the distance between the diffuser and the cap is 0.25*D.

Can it be installed on a chimney?

By installing a deflector, unlucky homeowners are trying to solve the problem of lack of draft. This happens when the chimney pipe is made incorrectly - the head falls into the zone of wind support of the roof, is raised to a low height, or a neighbor has built a tall building nearby.

The best solution for insufficient draft is to raise the chimney to the required height. Why is it undesirable to jam various attachments onto the head:

1. It is prohibited to place umbrellas and other exhaust devices on pipes that discharge combustion products from gas boilers. These are safety requirements.
2. When burning, stoves and solid fuel boilers emit soot that settles on the internal surfaces of chimneys and caps. The deflector will have to be cleaned, especially the rotating one.
3. At the bottom of a properly constructed smoke channel there is a pocket for collecting condensation and excess moisture. There is no point in covering the pipe from precipitation; it is enough to attach a nozzle at the end that protects the insulation of the sandwich.

The heads of stove flues can be equipped with umbrellas, but a turbo deflector is definitely not needed there. The topic of installing hoods on smoke exhaust ducts is covered in detail in a separate material.

How to build a deflector yourself

The deflector has its own parameters. So, its height should be 1.6-1.7 from the internal diameter of the chimney duct, and its width should be 1.7-1.9. Diffuser width – 1.2-1.3. But first, let's decide on the material from which it will be made:

If your chimney has a hole, birds often find it tempting to get inside. Small brownish black birds with a penchant for building nest in chimneys. Having these birds in your chimney can be quite annoying - they are vocal little buggers!

When you find yourself in difficulty with smokestacks, which are classified as an endangered species, there is little that can be done legally. The Migratory Bird Treaty Act, a federal regulation, prevents the removal of swift eggs and chimney chicks. The best thing you can do with quickies is to clean up after they leave. Technicians can be called in later to clean and remove nest residue from the chimney.

• Copper;
• Galvanized iron;
• Stainless steel.

Why copper if it is such an expensive material? The fact is that the deflector is located in one of the most inaccessible places in the bathhouse, and therefore, so that it does not have to be repaired, it is better to make it as resistant to atmospheric conditions as possible. And copper is the best in this regard.

Chimneys and most other birds are less likely to return to a nesting site if the nest has been removed. Several animals can get into your chimney, including squirrels and bats. Raccoons, usually females, enter chimneys to give birth and care for the pups. Terrible as they are, mother raccoons sometimes manage not only to get inside the chimney, but to pass through the smoke shelf or directly above the fireplace. If they have gotten this far, there is a good chance they will eventually break into your home. If not, you'll probably have to at least deal with various animal odors.

And here's how to make a deflector:

1. Draw on cardboard an outline of all the main parts, such as the cap, diffuser and outer cylinder.
2. Transfer everything to metal and cut using metal scissors according to these patterns.
3. Connect the parts to each other using rivets, bolts or welding.
4. Make brackets from a strip of metal - you will use them to secure the cap to the surface.
5. Attach a reverse cone to the cap.

The deflector itself must first be assembled, and only then installed on the roof. We first install the lower cylinder and secure it with bolts and nuts. Using clamps, we attach the diffuser to the lower cylinder, and on it - a cap with a reverse cone.

A raccoon is an animal you never want to hang as they are known for carrying various diseases. Raccoons are home to bugs like fleas and ticks that you or your pets can get, as well as diseases like rabies and roundworm.

Luckily, there are ways to remove mom and her babies from the chimney. If you don't mind the smell, items such as predator urine can get rid of raccoons. A humane method of removal is a live trap. You'll probably want to catch the mother while she's going through or even trying to scare her in some way. The babies still can't handle most of the fighting, so it's fairly easy to reach the fireplaces and grab them.

Purpose and use of deflectors

As a rule, chimney systems are considered the most important element of the entire heating system, because it is the operation of the chimney that affects the process of fuel combustion and the removal of all combustion products from the system and the house in particular.

The entire process of operation of a heating boiler depends on a high-quality air flow and on the complete removal of smoke from the system. Without the proper amount of oxygen, the combustion process is impossible, and food residues in a living space can seriously harm the health of residents.

In order to organize the correct level of draft in the system, you need to know some features of the chimney, the design and organization of which must be correct. First of all, it is worth considering the required cross-section of the pipe intended for air inflow and outlet. Important factors include the height of the chimney and its configuration. Now let's look at these requirements in more detail.

The choice of the required cross-section directly depends on the power of the thermal energy generator. The smoke exhaust duct or passage itself must be of a vertical type and straight enough so that no air pockets are created during operation.

In the event that compliance with these requirements does not produce a tangible result, it is worth resorting to the use of a deflector, which is mounted on the top of the chimney pipe.

The principle of operation of the deflector is to use the wind as an additional tool in leveling or increasing the level of draft in the system. Externally it looks like this. At the end of the pipe, a part of the system is installed that has a larger internal diameter than the chimney itself.

A strong wind allows you to create a rarefied space in the deflector, into which all combustion products remaining in the chimney move.

Among other things, the deflector has additional useful functions that have a positive effect on the entire operation of the chimney duct. With the help of such an element, you can protect the system from rainwater and snow getting into it in winter. As a rule, this helps the system function efficiently in any weather.

What is it needed for

The main thing when calculating the parameters of a chimney is to create sufficient draft capable of removing combustion products from the combustion chamber of a solid fuel stove due to a significant pressure drop. To do this, select the required channel diameter, material, cross-sectional shape and pipe height.

A strong wind can blow air into the mouth of the canal, thereby preventing the exhaust gases from escaping. An extreme case is the effect of draft suppression, when the boiler exhaust is not able to overcome the resistance and flows back into the room, which is, in principle, unacceptable.

It is not enough to close the mouth of the chimney from external air flows, but there are no optimal designs for this. It is better to use the power of the wind itself to avoid negative consequences and even further increase traction, which is what the deflector does very well.

Self-production of the device

To work you will need:

• galvanized or stainless steel sheet 0.5-1 mm thick;
• metal scissors;
• riveter;
• drill;
• a sheet of thick paper or cardboard.

The most important stage is drawing up a drawing. To do this, you need to measure the internal diameter of the chimney and calculate the product parameters according to the table.

If the internal diameter of your chimney differs from the parameters given in the table, calculations are performed as follows:

• the diffuser width is 1.2 d;
• width of the protective umbrella – 1.7-1.9 d;
• the total height of the structure is 1.7 d.

Both measurements and calculations must be as accurate as possible so that there are no difficulties during the installation of the structure and its subsequent operation. If the pipe has a square cross-section, then the deflector must be made square, although the angularity of the body slightly reduces the efficiency of the device.

If the design must have a reverse cone (Grigorovich deflector), the diameter of the protective umbrella is made 3-4 cm larger than the diameter of the cone. After assembling both elements, the cone is applied to the inside of the umbrella and outlined around the perimeter with a marker. Then make two cuts on the protruding part of the umbrella and bend the resulting strip inward. In the same way, make another 6-8 strips at an equal distance from each other, bend them inward and securely fix the reverse cone without additional fasteners or welding.

It is more convenient to attach a cap with a reverse cone to the diffuser with construction pins. To do this, before installing the cone on the umbrella, three holes are drilled around its circumference, the ends of the studs are inserted and the nuts are tightened. Then put the umbrella on top and fix the cone in the manner described above. At the top of the diffuser, on the outside, hinges made of tin or aluminum are riveted and the lower ends of the pins are inserted into them. This design withstands strong gusts of wind, serves for a long time and reliably.

In a similar way, you can assemble a deflector of any type, the main thing is to draw up the correct drawing. The only difference will be in the number and shape of parts. The finished device only needs to be mounted on the chimney.

Calculations and drawing

The TsAGI deflector is a very common device, and it can always be purchased in specialized stores and construction markets. In addition, it can be made to order by paying a tinsmith a fairly decent amount of money for its execution. But such a device can always be made independently, using calculation tables given in specialized literature and on the Internet.

If you decide to make this device yourself, then first of all, you should decide on the dimensions. It is necessary to build on the diameter and cross-sectional shape. The figure below shows a general drawing of a collet deflector for a circular duct cross-section.

• d is the internal diameter of the head of the ventilation shaft, and, accordingly, the narrow part of the diffuser.
• 1.25d – wide part of the diffuser.
• 1.2d – ring height.
• d/2 – distance from the narrow part of the diffuser to the lower boundary of the ring.
• 1.2d + d/2 = height of the entire diffuser.
• 2d – ring diameter.
• 1.7d – umbrella width.

How much does a deflector cost?

Ventilation devices are calculated together with the entire system. Deflectors of a specific model can be purchased for the required pipe diameter.

Table. Prices for deflectors

Deflectors are often made in artisanal workshops and small workshops (in this case, the product may not have a specific name or connection to the model). An indicator of the quality of the company’s work will be the product passport indicating the dimensions of the parts, steel grade and other details.

Making your own weather vane deflector

The weather vane allows you to reduce the height of the pipe by increasing traction, since it is always in the right relationship with respect to the wind, prevents precipitation from entering the pipe and decorates the roof.

Tools and consumables for work

To make one of the options for a weather vane on a chimney pipe with your own hands, you need to add to the above tools and materials:

• set of wrenches;
• pipe section;
• a metal (preferably stainless steel) rod or a ready-made pin;
• die for cutting threads on the rod;
• tap for cutting threads for fixing bolts;
• bolts for fixing bearings in the pipe;
• 8 nuts that will need to be screwed onto the rod to secure the bearings and secure the deflector housing.
• two bearings, the size of which is selected according to the diameter of the rod and the internal diameter of the pipe.

Step-by-step instructions and important notes

Operating procedure:

1. Initially, a drawing is made, according to which patterns for parts are then made from a sheet of galvanized steel.
2. Using patterns, apply the contours of the deflector elements onto a steel sheet with a special chalk or marker.
3. Metal scissors are used to cut out parts from a metal sheet.
4. The deflector body is assembled from the prepared elements by drilling holes and fastening them with rivets. You must remember to make brackets with which the body will be mounted on the rod.
5. Cut off a rod or pin of the required length so that it is enough to secure the bearings and fix the deflector body.
6. If a rod is used, the thread is cut using a die.
7. Next, two bearings are attached to the stud with the distance between them necessary to create sufficient support when the deflector-vane rotates. To secure each bearing, first screw on the first nut, then put the bearing on the axle, then screw on the second nut and tighten the nuts until the bearing is well secured.
8. Cut the pipe to the required length.
9. Holes are made in the pipe where the bearings are located. Use a tap to cut the threads for the bolts that will secure the bearings in the pipe. Holes are also prepared for attaching supports that secure the entire device.
10. A ring is made from a steel strip to secure the deflector to the chimney.
11. Cut sections used as supports for attaching the block with bearings to the ring securing the product to the chimney.
12. The final assembly of the product is carried out using rivets and fixing bolts.

There are many options on how to make a deflector for a pipe with your own hands. Everyone chooses for themselves what type of device is best suited. It is only necessary to note that such a design, placed on a pipe to remove combustion products, performs several useful functions - it increases draft when removing gases, protects the chimney from debris and precipitation getting inside. After installing the deflector on the chimney, the heating efficiency in the house increases significantly.

Types and schemes

The entire variety of trade names of smoke deflectors fits into a limited number of design types and aerodynamic designs. First of all, according to their interaction with the natural draft of the chimney, deflectors are divided into:

• Active - with a built-in working smoke exhauster. To ensure the specified characteristics of the deflector, the smoke exhauster must operate continuously while it is burning in the firebox.
• Active-passive - a low-power smoke exhauster for extreme cases: complete calm, storm, excessively intense fire, etc. The minimum permissible technical characteristics of the chimney are ensured even when the smoke exhauster is turned off.
• Passive-active - the deflector creates a small amount of its own thrust in a non-volatile way.
• Passive – there is no deflector’s own draft.

We do not further consider active deflectors as energy-dependent and not optimal for low-power home heating devices. Of the active-passive ones, we will consider one, designed for a low-power 12 V fan and suitable for DIY manufacture.

Aerodynamic designs of chimney deflectors

According to the aerodynamic design of the chimney deflector, it is possible to make a trace. way (above in the figure):

1. Aerodynamically imperfect (incomplete) - in the space occupied by the deflector there is a “pocket” - a weathering area in which accumulation of air, flue gases or a mixture of them is possible;
2. Aerodynamically fully open - there is no wind pocket, but the wind has free access to the working space of the deflector;
3. Aerodynamically perfect closed - there is no wind pocket, the wind does not have free access to the working space;
4. Deflector-vane (see below);
5. Vortex deflector.

An aerodynamically perfect closed deflector is the most complex structurally and technologically, but has a huge advantage: due to heating of the shell, almost all aerodynamically perfect closed deflectors provide their own energy-independent thrust. This is the only passive type of deflector that can increase the natural draft of a chimney in complete calm.

Note: an aerodynamically perfect closed deflector is the TsAGI deflector mentioned above. This aerodynamic design was invented precisely at TsAGI.

Vortex deflectors are easily recognized by their “ragged” design with sharp protrusions. There is still much that is unclear in their aerodynamics, as in vortex aerodynamics in general (the Navier-Stokes equation was solved in general form only 2 years ago). It is absolutely impossible to predict the behavior of a vortex deflector under any external conditions with any chimney. Therefore, vortex deflectors are not considered further. Whether or not to believe their manufacturers is your own business.

Aerodynamics

There are enough diagrams of flue gas flow in deflectors in publicly available sources. But from the point of view of the homeowner and the craftsman, the nature of the interaction of the deflector with the natural draft of the chimney and the wind in the wake is more important. aspects:

• Will the deflector worsen the original draft?
• Is the deflector capable of increasing the initial thrust in calm conditions?
• How much and how does the deflector increase wind loads on the pipe?
• How prone is the deflector of this design to icing/clogging and is it easy to clean?

Then it is better to consider the wind not according to the meteorological scale, but according to the rough gradation of force and the dynamics of the velocity field:

1. calm;
2. weak/medium (moderate) – up to 6 points on the weather scale;
3. strong – 6-8 points;
4. very strong – over 8 points;
5. gusty - the wind of any strength is really gusty, or sharp (strongly sloping up or down), or turbulent.

An idea of ​​the aerodynamic properties of passive smoke deflectors is given in Fig. higher.

Simple cap

An ordinary chimney smoker in the form of an umbrella, if it is made in the form of a Grigorovich cone, is not so bad:

Chimney with a tent-shaped chimney-umbrella.

• With a massive heat-intensive chimney, it keeps the draft within the permissible limits for a wood/coal stove in even winds up to a severe storm (10 points).
• In any wind, up to hurricane force, it does not create destructive loads on the pipe; It's more likely to break loose and fly away.
• Structurally simple.
• It is slightly coked and clogged, and is easy to clean as part of the annual inspection and maintenance of the chimney.
• Due to imperfect aerodynamics, it is little sensitive to the configuration of the umbrella. If the house is in the wind, the chimney-umbrella can be made into a tent (see figure on the right), which simplifies the work and provides greater opportunities for its design.
• With a 2-3 channel chimney (see below) it provides technical performance (except for increased draft in calm conditions) no worse than an aerodynamically perfect closed deflector.

The disadvantages of an imperfect smoke deflector are also quite serious:

1. In calm conditions, the initial draft decreases the more strongly, the more intensively the stove is heated. What is especially dangerous in the harsh, quiet winter: the stove can choke and puff out fumes.
2. In strong winds it can create excess draft, which sharply reduces the efficiency of compact channel stoves (for example, Dutch ones with 2.5-3.5 bricks) and fireplaces.
3. In very strong/gusty winds, blowing into the pipe and causing reverse draft cannot be ruled out.

In general, an imperfect deflector-umbrella is the optimal smoke vent for a brick chimney of a properly built and well-maintained solid fuel house stove, operated in places where hurricanes and storms are extremely rare. There are ways to make a smoke umbrella uninflated (see below), but they complicate it to the point that most often you have to choose an aerodynamically complete or perfect deflector.

Open

The aerodynamically open deflector does not reduce the initial draft and, in any wind, keeps it within the limits acceptable for stoves and boilers using solid, liquid fuel and gas. It freezes quite heavily, becomes coked and littered, but is easily accessible for cleaning. Its disadvantages are:

• A streamlined body of rotation instead of a cap is a technologically complex unit.
• The resulting vector of wind loads is such that an aerodynamically open deflector tends to collapse the pipe, while an umbrella tends to fly off it.
• In winds stronger than force 8, the lateral load on the pipe increases sharply and then grows according to a power law.
• It does not absorb dynamic loads from gusts of wind well, so an open deflector cannot be installed on a brick pipe.
• Unsuitable for pyrolysis heat-generating devices: in a strong wind it immediately sucks out the pyrolysis gases and the stove/boiler goes out.
• Not very suitable for design: blotches and figures spoil the overall aerodynamics. The only places where it is possible to place decorations are the upper pole of the body of rotation and the lower edge of the diffuser (see below).

Note: at one time, we and the USA conducted experiments on the use of open deflectors on steam locomotives to increase efficiency at low speed. The result was disastrous - at mid-speed a tongue of flame appeared from the pipe, and none of them could accelerate to the design speed.

In general, an aerodynamically open deflector is suitable for all types of heating devices, except pyrolysis ones. Provided that the deflector is inspected and cleaned at least once every 2 months, and the draft is checked before each firebox. Very well suited for chimneys with insufficient draft and, especially, for sauna stoves: there have been no cases of fires in saunas due to an open deflector. Properly heating a bathhouse is not an easy task, and checking the deflector will not significantly complicate it.

Note: there are types of open deflectors that create virtually no lateral loads on the pipe and are suitable for fragile ceramic and glass chimneys, see fig. on right. However, dust, debris and soot accumulate in the open rotating body, which spoils the aerodynamics of the device and makes it difficult to clean. Therefore, manufacturers recommend such products only for gas boilers in places with not very dusty air.

Perfect

The advantages of an aerodynamically perfect closed deflector are partially indicated above. Besides:

• The aerodynamically perfect closed deflector ensures stable draft in any external conditions, sufficient for any household stoves and boilers.
• It does not clog or freeze inside, and ice and dust outside have little effect on its operation.
• With minor modifications it is suitable for use as both smoke and ventilation non-volatile, see below.
• It perfectly absorbs dynamic loads from wind gusts and is therefore suitable for installation on pipes made of any materials.
• 2-3-4 chimneys can converge into one oval, triangular or square shell in a bundle.

The disadvantages of a closed deflector are not so significant:

1. The lateral force on the pipe in a strong wind gives more than an open one, but then with increasing wind it increases linearly, i.e. the pipe under the open deflector can always be reinforced or reinforced with guy wires.
2. Quite complex structurally and technologically.
3. Unsuitable for design: any blotches and figures spoil the overall aerodynamics, and the coloring only enhances the utilitarian appearance of the deflector.

Grigorovich deflector manufacturing stages

The simplest product is the Grigorovich device, which is easy for most people to make.

Calculations and preparation of drawings

When drawing drawings and sizing this product, the following ratio applies:

• the height of the structure is approximately 1.7d;
• the cap must be made with a width of 2d;
• The diffuser width should be about 1.3d.

The symbol d refers to the diameter of the smoke channel. If a different size ratio is used during manufacturing, this will negatively affect the efficiency of the created device.

Based on the drawn drawings, patterns are prepared that are used when cutting galvanized iron into elements, from which the product is then assembled. To do this, transfer the outline of the elements in expanded form and in full size onto the cardboard, using a ruler, tape measure and pencil. When making a deflector for a chimney pipe designed by Grigorovich, prepare patterns for the outer cylinder, diffuser and cap.

Stages and nuances of making a deflector

Next, the following work with metal is performed:

1. Using prepared patterns, outlines of the necessary parts are applied to sheets of metal, outlining cardboard figures with special chalk. If special chalk is not available, you can use a simple pencil. Add 20 mm to the contour of the parts in places where they overlap, which will allow you to maintain the required configuration of the finished elements during assembly.
2. Using metal shears, the elements necessary for assembly are cut out of galvanized metal, thereby preparing the expanded outer cylinder, diffuser, and both parts of the cap - the umbrella cap along with the reverse cone.
3. Then, using a hacksaw, metal strips or a corner are cut into pieces of the required length, through which all the elements will be connected into the finished product.
4. The parts are given the required shape by folding and bending them in a certain way.
5. The next operation is assembling the product. The elements are placed on top of each other and, using an electric drill, the necessary holes are drilled. Using rivets placed in prepared holes, the parts are fastened together.
6. To install the Grigorovich device on a chimney, you can use two options - in the first case, through holes are drilled at the mounting location, through which the structure is fixed with fasteners on the chimney, and in the second option, a clamp is made from a strip, through which the deflector is fixed to the pipe.

Application of deflectors

The main quality of deflectors for which they are used is the ability to increase traction by diverting external air flows. Regardless of the design, any deflector works on a single principle - the air bypassing the obstacle creates a low-pressure zone, due to which the draft in the chimney increases. A good deflector can increase the efficiency of a smoke exhaust system by 20%.

In addition, the deflector has an additional function that occurs indirectly - an obstacle installed on the chimney pipe prevents precipitation and various debris from entering it.

A simple deflector consists of two cylinders, one at the bottom and one at the top, and a protective cone, also called an umbrella. The bottom cylinder is usually part of a chimney made of metal or asbestos cement. Galvanized metal is used to make the deflectors themselves.

There are several standard options for deflectors:

• TsAGI deflector;
• "Volper" with a round body;
• Grigorovich deflector;
• Open deflector Astato;
• H-shaped;
• Star-shaped "Shenard".

Different types of deflectors are used in the following types of structures:

• Collective and private ventilation shafts;
• Collective and private chimneys;
• Systems for the removal of gases and combustion products;
• Garbage chutes.

Types and characteristics of pipe deflectors: main differences

If you look at the photo of the deflectors, you will notice that they all look different, but nevertheless perform the same functions

Therefore, before giving preference to one of the models, you should pay attention to the following criteria:

• material of manufacture;
• operating principle;
• design features.

Basically, all models are made from the following materials:

• aluminum;
• of stainless steel;
• galvanizing;
• copper;
• plastic;
• ceramics.

Note! Ventilation specialists believe that deflectors made of steel or aluminum are optimal in terms of price/quality ratio. Copper devices are also good, but due to their high cost they are used quite rarely. The deflector can be made of aluminum, stainless steel, galvanized, copper and plastic

Devices are divided into the following types:

• TsAGI, characterized by the presence of a ventacal expansion - diffuser;
• Volper cylindrical ventilation fungus;
• cap-weathervane, in common parlance - “sycophant”;
• H-shaped deflector made of pipes;
• turboreflector, which is a spherical rotary nozzle;
• static-dynamic device of open type Astato.

Some include in this list regular umbrellas installed at the top of the channel. It should be understood that this kind of device only helps to protect the ventilation from rain, but does not in any way affect the draft.

Open structures also differ in shape; the following devices are considered the main ones:

• flat;
• semicircular;
• with opening lid;
• gable.

In addition to the fact that devices are divided according to the type of weather vane, they are also classified according to the principle of operation:

• rotary;
• deflector;
• turbine

The operating principle of the device can be rotary, deflector or turbine.
Chimney deflectors are primarily installed to improve draft, which removes smoke and carbon monoxide outside. In addition, after installing the device, heat transfer increases, and the fuel burns better. Various photos of chimney deflectors also make it clear that with the help of the device the pipe is protected from precipitation and other debris brought from the outside.

Air conditioner deflectors, which differ in appearance from conventional devices, can be classified as a separate group. This design is a reflective screen that redistributes the air flow. Thanks to this, the beam of cool air is not directed directly, but parallel to the ceiling. Even though the air is dispersed, the pressure does not change.

Errors and problems with the device

With the deflector, as with all devices, troubles can arise. One, the biggest and completely preventable one is incorrect work. This happens if the device was selected the wrong size. It can simply fall inside the chimney pipe, closing the path for combustion products to escape.

To avoid this situation, you need to pay attention that the diameter of the deflector pipe must be equal to the diameter of the internal chimney pipe. If the chimney is brick, and the installed device has a round cross-section, then you cannot do without the appropriate adapters

If the chimney is made of brick, and the installed device has a round cross-section, then you cannot do without the appropriate adapters.

The second mistake when installing a deflector is choosing a rotating model for areas with cold and snowy winters. Such a solution is fraught with icing of the device, and after a few days it will be covered with snow and not only stop rotating, but will also significantly interfere with the normal operation of the chimney.

To clean everything by removing snow and ice, you will have to climb onto the roof, and this is not the most pleasant activity on a cold and snowy day.

The third problem is the ineffectiveness of the deflector.

The problem may arise if the installation location or model is incorrectly selected:

• the body of the device is poorly blown by winds from different directions;
• in areas with gusty winds, an H-shaped deflector will be more effective;
• you should avoid installing the device in the aerodynamic shadow zone of trees and taller structures located nearby;
• the device must be located above the roof ridge and above other structures if they are present near the chimney.

If the deflector turns out to be ineffective, then it is necessary to look for the reasons for the backdraft of the chimney.

The fourth problem is the breakdown of rotating models. The fact is that the mechanisms that ensure rotation require maintenance. More precisely, you must not forget to periodically carry out maintenance on individual parts of the deflector and lubricate the bearings on time.

If the device was made by hand, and the material used turned out to be cheap and of poor quality, then everything can rust very quickly. In this case, you will soon have to replace it with a new deflector.

Another problem is when a simple cap is installed instead of a deflector. It may become icy and covered in snow. This will have to be fixed. It is dangerous if this situation occurs at night and all combustion products remain in the house. This is fraught with death for all household members.

Therefore, you need to install the deflector right away and not experiment with different canopies. If you don’t want to build an amplifier from scrap materials, you can always buy the model you like and install it on the chimney yourself.

It is necessary to take care of the normal operation of the boiler and the effective removal of combustion products at the heating design stage. Useful information on chimney construction is presented in this article.

The nuances of installing wind hoods

When installing the deflector, you should be guided by SNiP standards.

The main attention is paid to the height of the ventilation pipe and hood:

• from 500 mm above the parapet/ridge of the roof, if the air duct is 1.5 m or less from the top of the roof;
• level with the ridge or higher, if the distance from the ventilation duct to the parapet is 1.5-3 m;
• not lower than the deviation line drawn at an angle of 10° from the ridge downwards, provided that the pipe is more than 3 m away.

On a flat roof, the deflector is installed at a height of 50 cm or higher.

When placing a ventilation shaft next to a chimney, it is necessary to maintain the same height of the air ducts. If these requirements are neglected, then stove smoke may enter the room.

Additional installation details:

• installation in the area of ​​the aerodynamic shadow of neighboring buildings is unacceptable;
• the deflector is placed in the free airflow zone, optimally if the cap is the highest part of the roof.

Installation of a round nozzle on a square air duct is carried out through an adapter pipe.

The requirements and method for installing a deflector on a boiler chimney are described in this article.

Installation of a deflector with a wind protection device

The deflector with wind protection is mounted as follows:

• Two bearings and a vertical axis are fixed in the chimney at two levels;
• A semi-cylindrical screen, a weather vane and a roof of the structure are successively installed on the axis.

The operating principle of this type of system is as follows:

1. When the wind direction changes, the weather vane rotates and pulls a curtain behind it, covering the chimney from the wind. As a result, smoke can escape from the leeward side of the chimney at any time.
2. Air flows pass tangentially over the semi-cylindrical screen and pull smoke behind them, increasing draft in the system.

To increase the efficiency of the structure, it is necessary to periodically lubricate the deflector bearings, and in the cold season, also remove ice that forms in the structure due to condensation. Taking into account the last nuance, we can say that such a nozzle on the chimney pipe from the wind can effectively protect only those structures that are located in warm regions.

Video description

We tell you how to protect your chimney from precipitation, which is better: a deflector or an umbrella for the chimney.

What is needed to assemble the Volpert-Grigorovich deflector

This is exactly the material that will be needed to assemble the deflector Source minprom.biz
To assemble the structure you will need:

• one sheet of galvanized sheet 0.32 mm thick (this is the optimal parameter, although you can also use 0.25 or 0.5 mm galvanized sheet);
• short aluminum rivets no more than 4-5 mm long;
• steel strip (it is better to choose a thinner one, but not more than 4-5 mm);
• fastening - everything here depends on the pipe on which the deflector will be mounted.

Stock up on the following tools:

• riveter with any (movable or fixed) head;
• any tool or device for cutting sheet metal;
• a steel ruler, although a short level or building square will also work;
• any compass;
• roulette, scriber;
• drill or screwdriver (preferably the latter) with a set of drills;
• extension cord 220 V.

Types and principles of design and operation of deflectors

Deflectors can be made in several generally accepted configurations and designs:

• TsAGI type deflectors;
• round type deflector (Volper);
• deflector designed by Grigorovich;
• open and H-shaped deflector.

The deflector itself has a design consisting of several separate parts. These parts include the lower type cylinder, diffuser and umbrella. The diffuser has the form of a cylinder located at the top of the element, and the umbrella protects the chimney from rain and snow getting into it. As a rule, deflectors are made from galvanized steel, which eliminates the possibility of metal corrosion by such debris.

The operation of the deflector does not have any features in its concept that even a novice master is not able to master. The wind flow goes around the entire deflector, colliding with it. This allows air to penetrate the upper cylinder of the deflector, increasing the draft in the chimney and drawing out all the smoke stagnant in the system. Due to the intensive movement of air inside the deflector, the traction force increases several times.

The design of this element allows you to increase thrust even when the wind flow moves in a vertical direction. For this purpose, there are special gaps in the upper part of the cylinder through which air penetrates into the ventilation and chimney systems.

It is worth taking into account such a thing as a downwind wind, which can make it difficult to remove smoke and reduce the level of draft in the chimney. Due to this wind flow, multi-directional wind flows are formed under the deflector umbrella, which clog the entire pipe.

Review of popular models

Let's take a closer look at the most common models of deflectors.

Ventilation deflector Tsaga

This model is considered the most popular. This device has a larger diameter than the chimney. Air flows flow around the device from all sides, as a result of which areas of high pressure are formed on the sides, and a vacuum occurs in the rear and front zones, increasing traction.

The design of such a product eliminates the protection of the chimney duct from precipitation. Therefore, after installing this device, additional installation of a protective cap is required.

The Tsaga deflector is suitable for use in both chimney and ventilation systems

Disc-shaped

A simple model that ensures fairly efficient operation of the system and high traction. The two main elements of the device form a protective canopy that prevents snow and rain from entering the chimney channel.

The lower part of the visor is covered with a cap, which is directed towards the chimney. This design allows the device to cope with the tasks assigned to it. The air flow can enter such a deflector from any side and, finding itself between the cones that form a narrowed channel, cause a vacuum.

Ball-shaped "Wolper"

This model has an almost identical device to the TsAGI deflector. However, there is one difference - the canopy, which protects the chimney channel from precipitation and debris, is located above the diffuser.

Grigorovich deflector

A very popular deflector model that increases draft in chimney and ventilation structures. This deflector is easy to assemble with your own hands. The design of this device includes the following components: a lower cylinder with two pipes, an upper cylinder, a cone and two brackets.

The smoke coming from the pipe ends up in the narrowed channel of the diffuser, causing a vacuum to occur. To assemble such a device, as a rule, a tin sheet or galvanized steel plate is used.

The Grigorovich deflector has a very simple design and is often made by hand

H-shaped

This model is used mainly in manufacturing plants or boiler houses that have high power. The installation of an H-shaped deflector occurs as follows: a pipe of a similar size is attached to the mouth of the pipe. In the central part of the pipe there is a special insert, which ensures a tight connection of the device with the chimney pipe. Two more tubes are fixed to the transverse pipe on the right and left, resulting in a device resembling the letter “H” is formed.

This design does not require a protective canopy, since the mouth of the chimney is already protected by horizontal parts. The H-shaped deflector enhances traction in any direction of air flow.

Rotating

Such a device rotates only in one direction. The circular motion provides additional efficiency of the device. In addition, this model provides protection for the pipe from precipitation and debris. Often used for gas-fired boilers.

Deflector "weather vane"

This model includes a rotating body. This device includes the following elements: weather vane, visors, bearing assembly. The rotation of the device is carried out due to the force of the wind acting on the weather vane. The weather vane type chimney deflector works on the principle of a ship's sail.

The weather vane deflector has a part in its design that rotates when the wind blows

The operating features of the device are as follows: air flows pass between the visors, so the air becomes rarefied. This model allows you to increase draft in the chimney, eliminate reverse draft and the formation of sparks.

Types of chimney caps

Before you make a chimney cap with your own hands, you need to decide what shape it will have, and then make a drawing. The most common forms that a chimney cap can have:

Chimney caps differ in design features and the material used in the manufacture of the product, but they all serve to enhance draft and protect the chimney from atmospheric phenomena.

When choosing an option, you should take into account the overall architectural appearance of the house. Thus, a chimney cap with a flat copper top is usually installed on houses in the Art Nouveau style. For a European-style home, it is better to make a canopy over the chimney with semicircular finials. Wind vanes with a gable roof serve for effective ventilation and protect the structure from filling with snow.

In wind vanes with a built-in weather vane, you can place a special damper, which in windy weather allows combustion products to escape unhindered. Chimneys with an opening lid are very practical; they allow you to clean chimney channels without much effort (see).

Protection of deflectors from low winds

Due to the presence of this feature of wind flows, deflectors began to be equipped with special protective devices that help increase the level of draft in the pipe in any weather. To do this, an axis is installed inside the chimney on two bearings located at different levels.

A semi-cylindrical screen, a weathervane and a cover are installed on the axis. It is this design that protects the entire chimney from the effects of the lower wind flow.

After the direction of the wind flow changes, the weather vane rotates, thereby closing the chimney from the wrong wind flow. Thus, any direction and strength of the wind is not able to block the path of the exhaust smoke, and the draft in the chimney remains the same power.

Do not forget that the deflectors are designed for round pipes, which can become a problem if you have an old brick pipe with a square cross-section. In order to solve this problem, special pipes are used that act as adapters.

For chimneys with a large square cross-section, which are built for fireplace heating systems, it is necessary to use adapters in the form of spacer legs that connect the pipe and the deflector itself. These legs are made of metal strips that can be galvanized or high-quality painted.

Brick pipes require an appropriate transition with an inlet in the desired direction, which allows you to connect a round deflector and a square chimney. In other words, it is not difficult to secure this element of the chimney system in the presence of any type and shape of chimney structures.

You don’t have to buy a deflector at a hardware store, because you can make it extremely easily with your own hands. To do this, you need to calculate the size and shape of the element, after which you can begin the manufacturing process.

On galvanized steel sheet it is necessary to draw the upper and lower cylinders of the future deflector, which can be easily done using an ordinary pencil. You can cut out the necessary elements using metal scissors, which can easily cope with this task.

Once these two parts have been cut and filed, which is required to properly join the two edges of one part, you can begin to secure these edges. As a rule, a welding machine, bolts or rivets are used for this.

It’s worth noting right away that connecting a galvanized steel workpiece using a welding machine is extremely difficult, because it burns through thin metal quite quickly. It is for this reason that rivets or small bolts are most often used.

The finished cone cap must be secured to the upper cylinder of the deflector. This is done using small brackets made of the same sheet steel. The brackets are secured to the pipe using rivets. Do not forget that the brackets should be attached only to the outer side of the deflector, so as not to create additional interference in the internal part for proper air flow and smoke extraction.

A reverse type cone must be attached to the element umbrella. In addition, the assembly of all parts of the deflector must be carried out directly on the pipe itself, which will allow for high-quality installation and fastening of each individual part of the structure.

Otherwise, it is possible to connect two elements of the system poorly, which will subsequently cause a malfunction of the structure and the entire chimney as a whole. In some cases, it is simply impossible to make this design on your own.

As a rule, this happens with brick chimneys, which require high-quality adapters or stands. From this we can conclude that it is much easier, more profitable and faster to buy this inexpensive element of the system than to try to make it yourself.

It is worth recalling that only galvanized steel can be used to make the deflector, which successfully resists the formation of rust, which negatively affects the life and quality of service of such a system element.

DIY ventilation deflector

Knowing about the structure and operating principle of the device, many owners decide to make a ventilation deflector with their own hands. From the point of view of hand-made implementation, the version of Grigorovich’s product is unrivaled, so we will consider the implementation of this particular option. The main advantage is that this ventilation works without electricity, all year round.

You should first prepare:

• stainless steel sheet type, can be replaced with galvanized steel;
• electric drill;
• fixing clamps, bolts, rivets and nuts;
• drawing tool for metal surfaces;
• compass;
• sheet cardboard;
• ruler;
• scissors for metal and paper.

Calculation of device parameters (Grigorovich)

We give you the simplest calculation option, without any formulas:

• The height of the deflector is 1.6 times the diameter of the chimney.
• the width of the diffuser is 1.2 times greater than the diameter of the chimney.
• The width of the cover is equal to two diameters of the chimney.

Based on the available dimensions and drawings, individual deflector elements are cut out of cardboard. Creating a rotating device requires certain skills, so it is better to practice on mock-ups and only then proceed to a metal analogue.

Manufacturing of the structure

The patterns must be attached to metal sheets, and then traced with a scriber. Next, the algorithm is simple - we use metal scissors to cut out the elements and details of the future design. The individual parts are connected to each other with rivets and bolts. If the mechanism is active, then it is better to fix the parts by welding.

Models of deflectors for ventilation systems made of cardboard

To securely fasten the rotating hood, you should prepare several curved metal strips that will act as brackets.

We fasten the brackets with rivets or bolts

As for the reverse cone, it makes sense to fix it at the umbrella.

Deflector

Installation work

The lower of the 2 glasses is installed on the exhaust chimney. The top glass is attached to it. For greater stability of the structure, the 2 parts are clamped with a clamp, and the same is done with the exhaust holes. The cap is pressed against the prepared brackets. If we are talking about a region where the wind direction often changes, it makes sense to equip the installation with a reverse cone, which will allow the unit to fully operate in any wind direction.

So, in this article we looked at what a deflector is in ventilation. To summarize, we can say that this is a simple and effective device that improves the ventilation of objects of any complexity, be it public buildings or residential buildings. A small element increases the performance of the ventilation system by 15-20%, reliably protecting the interior space from precipitation, small particles, debris and dust.

Possible problems associated with system smoke

Most often, smoke in the chimney system occurs for the following reasons:

• strong wind gusts, as a result of which air under strong pressure penetrates into the pipe, which causes a decrease in traction force and smoke in the living room;
• the smoke passage is too narrow, which is not able to provide the system with the required level of draft;
• insufficient lifting height of the chimney pipe, which does not allow the formation of the required pressure and draft force in the pipe.

Statistical type deflectors are designed specifically to solve all these problems, allowing the chimney to work extremely correctly and efficiently. The use of this element of the system is relevant for private or collective ventilation and chimney systems. As a rule, there are no restrictions on the use of this auxiliary device if its location does not interfere with other functions of the chimney.