Condensation in the chimney - what to do? Condensation in the chimney pipe - causes and methods of eliminating the problem. What to do with condensate from a gas boiler

Modern man is very thermophilic. If you, our dear reader, have own house, then the problem of heating it has to be solved independently. But modern heating equipment is different from the fireplaces of the past; Along with an increase in efficiency, the complexity of the design increases and the maintenance of units becomes more complicated.

When modern boilers, stoves and fireplaces operate, condensation inevitably forms in the chimney.

Whatever type of fuel you use, you burn hydrocarbons. Coal, coke, firewood, fuel oil, gas, pellets - everything consists of hydrogen and carbon with small admixtures of sulfur and some others chemical elements. Any fuel also contains a small amount of water - it is impossible to completely remove it. During combustion, they are oxidized by atmospheric oxygen and the output is water, carbon dioxide, other oxides.

Sulfur oxides at high temperatures react with water and form very aggressive acids (sulfuric acid, sulfurous acid, etc.), which also enter the condensate. A few other acids are also formed: hydrochloric, nitric.

Why is condensation dangerous?

There are two immediate dangers when condensation forms:

when condensate freezes in the form of ice at the mouth of a pipe or deflector, the cross-section of the pipe overlaps until it is completely closed - as a result, the draft decreases, the draft may overturn (reverse draft), combustion products (carbon dioxide and carbon monoxide) will enter the living room and cause severe poisoning of people; hot gases may cause a fire.
in very large quantities, the liquid can extinguish the fire, for example, in a fireplace - with a direct-flow pipe).

Consequences of condensation in pipes

Aggressive acidic environment, collecting on the walls chimney, leads to its rapid destruction - acids corrode the steel, corrosion occurs - the metal quickly rusts and “burns out”. are also destroyed by acid condensate.

In addition, condensate flowing into the boiler furnace also destroys the heating unit (and in very large quantities it can extinguish the fire in the furnace).

A large amount of moisture settling on the walls can also lead to unpleasant consequences:

moisture settling at the top brick chimney, leads to its getting wet and constant freezing and heating - this leads to the rapid destruction of such a pipe;
condensate flowing into the boiler furnace also destroys the heating unit;
When a steel pipe “burns out,” moisture gets into the insulation, freezes and thaws—the pipe also collapses very quickly.

The photo below shows the consequences of repeated freezing of a brick pipe.

Reasons for the appearance of condensation in the chimney pipe

The exhaust gases contain water and other liquids in the form of steam. When the gases are cooled, the steam becomes supersaturated, the water collects in droplets and tends downward - this is the most main reason the appearance of condensation. In a flow of hot gases, this process occurs near the colder walls of the chimney - and it is there that drops of liquid settle, forming condensation.

When considering the reasons for the appearance of condensation, it should be borne in mind that there is no smoke without water vapor; the presence of liquid collecting on the walls of the chimney cannot be avoided.

Reasons for the increase in the amount of condensing liquid in chimneys:

, especially from single-layer galvanized pipes;
the pipe is too long - significant cooling of the smoke occurs in the upper part;
low exhaust gas temperature. This is especially true for modern units with a heat exchanger for connecting the heating system. It is desirable that the temperature of the gases leaving the furnace head be at least 100 °C;
a large difference between the temperature of the ambient air and the exiting smoke;
raw fuel (especially firewood);
narrowing of the hog's clearance due to soot deposits and, as a result, a decrease in traction;
low combustion temperature with incomplete combustion of fuel due to insufficient supply of fresh air, which leads to low smoke temperature and low draft;
design flaws of the chimney - the presence of horizontal and inclined sections (over acceptable by standards 2000 mm horizontal projection); discrepancy between the cross-sectional area of the channel and the design area (it is bad to both reduce and increase the cross-section);
the ingress of precipitation in the absence of a deflector or cap increases the amount of liquid in the chimney channel;
Rough walls inhibit exhaust gases more and collect more condensate than smooth ones.

Ways to get rid of condensation

It is impossible to completely eliminate condensation. If you think that “in the past, stoves were heated for centuries and there was no condensation,” then you should keep in mind that now fuel is burned almost completely, the efficiency of heating units is greater than that of more primitive models wood stoves and fireplaces of past centuries, the temperature of the flue gases is lower - hence the greater amount of aggressive liquid in the chimneys.

It is possible to achieve such operation of the equipment and pipe design that almost all the condensate will be carried away into the atmosphere by very hot smoke - but it will also carry away a considerable share of heat and your money.

But all is not lost - measures can be taken to reduce the amount of condensed liquid

Insulation of the chimney channel

Alpha and omega chimney devices. Any chimney must be insulated all the way to the top. It is also recommended to additionally insulate old brick pipes above the roof and in the attic.

An uninsulated chimney has no right to exist at all.

Pre-drying of fuel

Firewood needs to be dried! First - under a canopy or in a spacious, ventilated barn, optimal time drying - one and a half to two years. Finely chopped firewood dries faster. Before use, let them sit for a week or more in a warm, dry room. Constantly burning wet wood will result in large amounts of moisture entering the smoke, wasteful wood consumption, incomplete combustion and the release of large amounts of soot (and the need for more frequent cleaning of the smoke duct).

Coal, peat - do not wet. Bring it into the room in advance, let it warm up and dry out the moisture that has settled on it. Pellets, briquettes - protect from getting wet, store in a dry, warm room.

Choosing the right fuel

Firewood, pellets, briquettes (especially firewood) initially have higher moisture content than firewood or fuel oil. But it is more reasonable to choose the type of fuel for a heating unit, based on the parameters of fuel cost, availability in your area, and the need to automate the heating system.

Chimney cleaning

The smoother the internal surface of the smoke channel, the better the draft and the more moisture will “fly into the chimney”. Therefore, the chimney should be cleaned of soot regularly, without waiting for the draft to deteriorate - at least twice a year. Cleaning methods - mechanical or chemical - are not of fundamental importance.

At different types fuel is formed different quantities soot For example, for gas boiler the amount of soot formed is minimal, for a coal furnace it is maximum.

- a completely affordable activity to do yourself. In our video you will see all the intricacies of chimney cleaning.

Using a steam trap

What to do if condensation flows along the walls of the chimney? Install a container to collect condensate. This is an absolutely necessary event in modern heating systems. Condensate drain - a container made of of stainless steel for collecting condensate, mounted in the lower part of the vertical channel, below the outlet channel or pipe of the heating unit, with access for emptying it. Sometimes a permanent drainage of condensate from the tank into the sewer is arranged. In modern metal “sandwich systems” and ceramic pipes The range includes ready-made sections for mounting such containers.

Old chimneys should also be modernized by integrating them into bottom part condensate drain glass.

Preventing condensation

Basic preventive measures to reduce the amount of condensate:

even at the design stage - compliance with all standards for the installation of a chimney system;
installation of a chimney without deviations from the project;
modernization existing pipes(you can protect the channel by inserting stainless steel liners; insulation);
increased traction by all accessible ways– installation of deflectors, smoke exhausters, rotary turbines; reliable air supply to the heating unit;
regular pipe cleaning;
use of dry fuel.

Chimney design requirements

Requirements for the design of chimneys are determined by SNiP 41-01-2003.

Primary requirements:

the height of the channel should not be less than 5 m;
the height of the pipe above the roof is at least 1 m for a flat roof;
pipe height at pitched roof determined depending on the ridge (at a distance from the ridge to the tip (horizontally) of 1.5 m - at least 0.5 mm; at a distance from 1.5 m to 3 m - flush with the ridge; at a distance of more than 3 m - angle between the horizontal and the line passing through the top of the pipe and the ridge should not exceed 10°);
the length of the horizontal hog should not exceed 1 m;
the sum of projections onto the horizontal of horizontal and inclined sections should not exceed 2 m, while the length of the vertical section increases by the same length.

Conclusion

We hope, our dear reader, that this article will help you understand the operating features of modern chimneys and choose one for your home. optimal design smoke removal systems, protect equipment from aggressive condensate. Subscribe to our newsletter - and you won't miss a new one useful information about construction and repairs and you can discuss it with friends on social networks.

Why does condensation form in the boiler and chimneys? This phenomenon is often accompanied by a pungent, disgusting odor. Where does this come from?

In general, any hydrocarbon fuel, which includes gas, coal, firewood, as well as oil and all its derivatives - all these types of fuel contain hydrogen, which is clear even from the name: hydrocarbons. When they are burned, water is also synthesized, which is in a vapor state as part of the flue gases.

In addition to the synthesized water, there is also moisture from the air, which is supplied to the firebox. In addition, there is moisture in the fuel itself. For example, greatest number contain firewood, and the least amount of water in coal.

All this water is in the flue gases in a vapor state with high temperature. At the exit from the furnace wood boiler The flue gas temperature can range from 600 to 800 degrees.

Passing further through the boiler heat exchanger registers and smoke channels, these gases give off heat and are cooled. When their temperature reaches the condensation temperature (dew point), then this phenomenon occurs. That is, water from a vaporous state is deposited on the colder surfaces of registers and walls of chimneys.

The dew point is far from a constant value. The condensation temperature depends on many factors, such as parameters such as absolute and relative humidity of gases, their temperature and even the content of excess air in them.

In practice, for wood-burning solid fuel boilers, the dew point temperature is considered to be approximately 40 degrees. That is, condensation will form on any surfaces below this temperature along the flue gases.

At the very beginning of the boiler fire, condensation forms on almost all surfaces until they warm up to a temperature above the dew point. And this point moves further and further from the firebox over time towards the head of the pipe.

When, finally, this entire system is warmed up, moisture will no longer condense on the surfaces of the system, but in the air outside the system in the form of white smoke from the chimney. And the moisture that condensed on the walls will now evaporate and move along with the flue gases to the exit.

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Dealing with condensation is not difficult. Of course, it is impossible to defeat the laws of physics and prevent it altogether, but it is possible to ensure that there are no cold surfaces in the path of gases or that they are cold minimum time from the beginning of the fire.

The first measure is mandatory insulation pipes, whatever it may be, brick, steel or whatever. The second measure directly related to boilers is to prevent the supply of water with a temperature below the dew point (40 degrees) to the heat exchange registers. We read about this topic in the article

When starting and warming up gas or solid fuel boiler Many owners notice a strange hissing in the boiler furnace, as if it were raining over the burner flame, and in some cases even the formation of a puddle of sweat in the boiler. Negative thoughts immediately pop into your head that you were sold a faulty boiler, what should you do now?

Let's go in order; firstly, before the boiler is ignited, the heating system is filled with coolant, and the leak should have appeared earlier; secondly, all boilers of our production undergo strict control before sale and pressure testing at high pressure for several hours; and thirdly, the reason for this is the appearance of condensation on the walls of the heat exchanger.

Condensate is a product of the transition of a substance during cooling from gaseous to liquid form. In other words, condensate is a liquid formed by the condensation of steam or gas. At the heart of all this is physical phenomenon dew point, for gas boilers The dew point is 30 0 C. For solid fuel boilers 35 0 - 40 0 C due to the larger volume of the heat exchanger, and the use of fuel, the combustion of which produces flue gases with high content moisture.

In practice, everything happens as follows: on one side the walls of the heat exchanger are washed cold water, on the other hand, hot gases from fuel combustion. The gases give off heat to the coolant, which means they cool, and at a temperature of about 30 0 C, moisture falls out of them, covering the walls of the heat exchanger with a thin layer. Then drops and streaks of condensate form, which causes corrosion of the steel firebox, leading to the adhesion of soot and ash into the solid fuel boilers, and consequently to a decrease in efficiency and service life of the boiler.

To avoid excessive release of condensate, it is recommended when starting the boiler to reduce the circulation in the system, let the boiler warm up the coolant in its heat exchanger to 60 0 C, and only then turn on the pump at low speeds. During operation of the heating boiler, do not allow the coolant temperature at the boiler return to drop below 30 0 C, which is achieved by installing mixing and recirculation circuits in the heating system.

Well installed and configured heating system plus economical And reliable boiler, will give you warmth and comfort in your home.

Comments

Sergey
#1 date: 25.11.2015, 11:54

Good afternoon. When burning wood in a solid fuel boiler long burning Swag 10 stands out a lot
condensate on the bottom door. Combustion temperature, supply 65 degrees. return 63 degrees. There is a three-way valve. Tell me what is the reason?

Valentina Vavrenyuk
#2 date: 26.09.2019, 13:24

Good afternoon. When the boiler heats up, water appears underneath it. What could be the reason!????

Condensation in the chimney - what to do?

5 (100%) votes: 2

During the combustion of fuel in a stove or fireplace, flue gases saturated with water vapor and soot appear. As they move through the chimney, they cool and steam begins to condense on its walls, and soot settles there. As a result, if too much condensate forms in the chimney, a black tarry liquid appears, which has bad smell and seeping through the masonry, and also creates dampness. All these factors lead to the stove getting wet and destroying it.

Why does condensation appear?

Condensation in the chimney pipe can form for the following reasons:

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Chimney pipe contamination. The accumulation of debris inevitably leads to the fact that the draft is reduced, because of this the heated gas does not pass through the pipe quickly enough. Ultimately, it comes into contact with air, and this causes condensation to appear.
Temperature difference when gas exits. During the cold season (winter and autumn) temperature regime inside the chimney is quite low. When heated gases enter it, wet precipitation is formed.
Fuel too wet. For heating private houses, it is best to choose well-dried firewood or other types of fuel. If this requirement is neglected, then when exposed to fire, internal moisture will begin to evaporate, which leads to its settling on the internal walls of the chimney.
External influences. This mainly happens due to precipitation if it has the opportunity to get inside the chimney.

Condensation formation in a brick chimney

It is very important to know how to get rid of condensation in a chimney pipe. Such problems can be solved by cleaning it, insulating it or protecting it from precipitation. You can choose any method based on the reason that led to this negative phenomenon.

Ways to solve the problem

Let's look at the main ways to get rid of condensation in a chimney:

Chimney cleaning

If condensation in chimney formed due to contamination, the product should be thoroughly cleaned.

To clean the chimney you can use several methods:

with the help of special chemicals, as a result of combustion of which soot deposits begin to decompose. These include the “Chimney Sweep” product;
through mechanical cleaning;
You can also use folk remedies.

Manual cleaning is performed using a cable (rope) of a certain length, a weight (it acts as a weighting agent) and a special brush. This device must be lowered slowly and smoothly inside the smoke channel from above.

As folk remedies usually use ordinary salt or potato peelings, which are poured into the combustion chamber during the combustion process.

No matter which cleaning method you choose, you must strictly follow safety rules.

Chimney insulation

What to do if the chimney pipe leaks mainly in the cold season? Often home owners have to deal with this negative phenomenon precisely because they did not pay enough attention to the insulation of the chimney.

The problem needs to be solved and mineral wool, any fibrous insulation, polystyrene foam boards, plaster.

Mineral wool and fiber materials are usually chosen for finishing metal or asbestos cement pipes. In order to insulate a chimney made of brick, it is best to resort to plastering.

Finishing the chimney with fiber insulation or mineral wool are carried out as follows:

Initially, it is necessary to cut the material into several parts so that it is convenient to wrap the pipe with them.
The prepared sections need to be fixed on the surface of the pipe; for this you will need metal wire or clamps.
For external protection of the laid thermal insulation, a metal box or foil is usually used.

To plaster a brick chimney, you need to perform a number of measures:

The wall of the brick pipe must be pre-equipped plaster mesh, for this purpose special bolts with an enlarged head are used. This is done in order to increase the adhesion of the solution to the surface to be finished.
The mixture of the first applied layer consists of the following components: cement, lime, water and fine slag. The thickness of the first layer should be approximately 35-40 mm.
When the starting layer is dry, you can proceed to the rest, 3-5 pieces.
After the plaster is finished, you need to wait until the material is completely dry, and then you should paint it decoratively in any color at your discretion.

It is believed that the plaster insulating a pipe should consist of at least 7 layers.

Protection of the smoke channel from precipitation

This procedure is carried out using caps specially designed for this purpose, which are usually present at the top of chimneys.

Some head models have built-in deflectors inside: due to this, the product not only performs protective functions, but has a positive effect on increasing traction. In the same way, you can reduce the amount of condensate in the chimney pipe of a gas boiler.

How to remove condensation in a brick chimney

Very often, the chimney for stoves is made of brick. If technology is followed during the construction process and all work is carried out in accordance with the requirements, then such a structure will successfully serve for a long time. for long years Moreover, this is a completely budget option.

If brickwork darkens, becomes damp, and streaks appear on it, this indicates the appearance of condensation. There are several ways to solve this problem. The first one is the essence this method lies in the fact that a steel pipe is placed inside the chimney, thanks to the smooth walls of which smoke does not linger for a long time, and accordingly, soot and condensation do not accumulate.

Another method involves a thorough inspection of the chimney. If you find cracks, irregularities, or cavities in it, then the deformed areas should be repaired or the chimney should be completely reconstructed.

How to get rid of condensation in a steel chimney

Chimneys made of steel. in popularity they are not inferior to brick products. They are universal, easy to assemble and operate. But it is precisely this type of pipe, due to the high thermal conductivity of steel and due to the thinness of the walls, that is most susceptible to the formation and accumulation of moisture.

There are several ways to solve the problem. Firstly, do-it-yourself insulation of the walls of the chimney. For this purpose they use thermal insulation materials. You can also buy ready-made insulated steel pipes() with a built-in layer of thermal insulation.

The next method is structural. The chimney layout provides areas with special devices for condensate removal - condensate collectors.

This device is steel element various shapes, which catches the flowing condensate into a special drain, which is highly resistant to corrosion.

A plug with a condensate drain can be installed in the pipe design, which is mounted on a tee located at the turn of the drainage system from an inclined position to a horizontal one.

If a tee is used in the chimney structure, then this installation principle is called “smoke”, if there is no tee - “condensate”.

Condensate collector- this is very important element, which, if possible, should be installed on the chimney for gas ovens and boilers.

This is due to the fact that the temperature of the flammable gases leaving them is very low, condensation forms quickly, water reacts with the gas combustion products, and as a result, the formation of acidic substances (sulfuric, hydrochloric acid) corrodes the pipe walls.

Therefore, acid-resistant stainless steel materials should be used, which will last longer. To prevent moisture from flowing down and destroying the oven, a condensate collector is installed in some areas with liquid drainage, for example, to the street or into a special container.

Condensate collector on a pipe

Prevention

To ensure that condensate forms in the chimney as little as possible, the following rules must be followed:

Place in a chimney duct made of brick metal pipe(i.e. they perform the “sleeving” procedure). This will make it much easier for you to clear soot from the channel. In addition, it is sealed and insulated: in this case, much less condensate is formed and it is removed faster.
A special device designed to collect condensate should be installed. It is best to place it in the area where the vertical and horizontal parts of the channel intersect: this is where it is most convenient to remove moisture from the gas flow. During maintenance of the condensate collector, it will be necessary to periodically remove accumulated liquid from it.
The fuel must be of high quality and well dried.
The chimney must be cleaned regularly. It is best to do this in mid-autumn, ahead of the start of the heating season.
If necessary, the chimney must be repaired immediately.

To summarize all of the above, it is worth saying that the appearance of condensation in the chimney pipe is an inevitable phenomenon. However, it is in your power to prevent this negative process in time. And regular preventative procedures will help reduce the amount of condensation formed.

Condensation is a physical phenomenon that occurs when there is a temperature difference between the environment and the walls of the smoke channel. As a result, moisture is produced, which adversely affects the condition of the chimney and gas boiler, forming puddles when working with it and reducing efficiency.

Moisture on the walls of the chimney

Causes

Condensation is intensely formed due to:

season and climatic factors;
fuel quality;
inappropriate material for combustion products exhaust pipe;
improperly designed chimney.

In winter, moisture on inner tube the chimney freezes, because its walls are cold, turns into ice plugs, and on top of the head - into icicles. Over time, the gas boiler operates, the pipe gradually heats up, the ice thaws, moisture flows to the pipe, disrupts the operation of the burner and negatively affects the general state chimney.

Increases condensation formation chemical composition fuel. When it burns, water vapor is released, which remains on the walls of the smoke exhaust channel and combines with moisture and salts of the flue gases. Thus, aggressive acids are formed that corrode the surface of the pipes.

The very principle of operation and design of the boiler promotes the formation of condensate. The flue duct system for gas heating appliances is cold. The temperature of the exhaust gases is insignificant (up to 120 °C) and does not have time to warm up the chimney, so moisture always forms on its pipe.

Due to the settings mode, the device operates periodically and turns off when the system has reached the specified temperature values, which also excludes optimal heating of the outlet channel.

Rust is a sign of condensation

The appearance of moisture in double-circuit boilers

In addition to the chimney, condensation also appears on water pipe 2-circuit gas boiler. It occurs due to the difference in water temperature in the supply channel and environment. As a result, the pipe becomes covered with rust and damages the equipment.

There are several reasons for this:

ventilation malfunction, check this by leaving the door in the room open at night, if the next morning top part the pipes are dry, the reason is poor exhaust;
unfavorable microclimate in the room, which is normalized by ventilation, air conditioning or installing a moisture absorber;
incorrectly set operating mode of the device.

Due to the peculiarities of the operation of a 2-circuit boiler, it is impossible to completely get rid of condensate, but a number of techniques will help, thanks to which the formation of moisture will decrease. These include:

thermal insulation of circuit pipes;
chimney insulation.

The following are used as heat insulators for the contour pipe: foamed polyethylene, polyurethane foam, mineral wool boards, liquid ceramic compositions and others. They are purchased in the store and selected based on the features and brand of equipment.

Features of pipe insulation:

Before installing the heat insulator, the pipe is sanded, treated with acetone and phosphoric acid, and epoxy putty or primer is applied;
thermal insulator diameter by 2-3 mm larger diameter pipes;
Before installation, the material is cut into pieces, the number of which depends on the length of the pipes;
when making a cut on a pipe, the technical cut is located at the bottom and is wrapped with a strong thread on top;
The space between the pipe and the insulation is filled with polyurethane foam.

Pipe insulation

The influence of pipe material on the occurrence of excess moisture

In a gas boiler, unlike an electric or solid fuel one, condensate is constantly formed, so the material and thermal insulation of the pipes for the chimney arrangement are very important and affect the safe and trouble-free operation of the device.

The optimal types of pipes for a gas boiler are:

made of stainless steel, resistant to aggressive acids, smooth, assembled according to the “sandwich” principle - a pipe of a smaller diameter is located in a pipe of a larger one;
sandwich pipes consist of internal and external contours, between which a thick layer of insulation (stone wool) is placed;
ceramic, the most expensive, are strong and durable, fireproof, heat up quickly and cool slowly, resistant to chemical compounds, easy to maintain, insulated with mineral slabs and expanded clay shell;
coaxial, do not form condensation, built on the “pipe-in-pipe” principle, where combustion products are discharged through one of them, and combustion products are supplied through the other Fresh air outside the room to ensure the process of maintaining the flame in the boiler, with high efficiency, is safe.

The shape of pipes is allowed only oval or round. A square chimney promotes increased soot accumulation. It is better not to use a brick or asbestos-cement channel to remove combustion products - they are destroyed by acid compounds, are not sufficiently sealed and thermally insulated, and absorb moisture.

Brick chimney affected by condensation

Is it possible to calculate the probability of condensation occurring?

Condensation forms when the thermal power of a gas boiler is unreasonably exceeded and causes burnout of the chimney walls. To ensure that the power of the equipment does not affect the formation of excess moisture, the optimal value is calculated.

For standard premises, the normal figure is 1 kW per 10 m2 of room. In rooms whose ceiling height does not reach 3 meters, the basis for calculating the power formula (MK, kW) are the following indicators:

UMC – specific power of the boiler associated with climatic zone residence and per every 10 m2 of premises;
S – area of the room in which the boiler is installed (m2).

The formula itself looks like SXUMK/10= MK. The WMC indicator is standard and equal to:

7-0.9 in the southern zones;
1-1.2 for mid-latitudes;
2-1.5 for the Moscow region;
5-2.0 for northern regions.

Burnt out chimney walls

If the boiler is 2-circuit, then to prevent condensation from forming, multiply the result obtained by 25%. For ceilings higher than 3 meters and a non-standard room layout, the boiler power (MK) is calculated using the formula:

Qt*Kzap, WhereQt– coefficient of predicted heat loss, Kzap – safety factor (1.15 for single-circuit and 1.2 for 2-circuit boilers).

V– room volume (m3);

Рt– difference between internal and external temperatures (°C) ;

K– dissipation coefficient, depending on the presence of thermal insulation of the room (from 3.0-4.0 in the absence of insulation to 0.6-0.9 for well-insulated rooms (with insulation of the floor, roof, walls and windows).

The final formula looks like V*Pt*k/860 = Qt.

Dew point

The process by which water vapor in the chimney begins to precipitate and form condensation is called “dew point.” It depends on the indicators of absolute, maximum possible, humidity, depending on the air temperature on that day, the actual air humidity in this moment and the differences between these indicators. You can find out at what temperature the dew point appears in the table below.

Dew point determination table

It shows that if the air temperature is 5 degrees Celsius and the air humidity does not exceed 70%, then the dew point appears at a temperature of -5 °C and moisture will begin to appear on the walls of the chimney.

Installation rules

To prevent condensation from accumulating, the chimney system must be:

waterproof;
hermetic;
protected from corrosion;
insulated.

These conditions can only be ensured correct installation chimney, the choice of its materials, insulation and sealing during the assembly process. A description of the nuances of these processes can be found in the video below, with a brief overview types of chimneys and requirements for their installation.

Key points:

the lower pipe is positioned with a socket towards the outlet;
all joints are treated with sealant;
vertical deviations within 30% are allowed;
the horizontal distance does not exceed 1 meter;
The cross-section of the pipes throughout the channel is the same.

T-shaped condensate trap

Forbidden:

use of a brick chimney;
the use of mushrooms and umbrellas at the head of the outlet.

To prevent condensate from collecting, it is necessary to have a condensate collector and a drain, ensuring good draft. It is important not to forget about routine cleaning of the gas boiler and preventive maintenance of the condition of the internal walls of the chimney.

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