Gas condensing boilers: the price is compensated by the efficiency of the equipment. A condensing boiler is the best solution for heating a private home. What does a condensing boiler mean?

They create a comfortable indoor microclimate and are a highly efficient heating system. Compared to traditional boilers, condensing wall-mounted boilers have an indisputable advantage - saving gas consumption by approximately 11-15%.

A double-circuit condensing gas boiler, like a single-circuit condensing boiler, works to heat the room using thermal energy released after complete combustion of the energy carrier has occurred. Inside the economizer there are combustion products that do not disappear, but turn into condensate and are used in the process of heat release.

A gas wall-mounted condensing boiler uses fuel energy to the maximum, resulting in real savings on space heating.

Operating principle, types of condensing boilers. Main Components

The essence of the operation of condensing boilers is that they take heat from both gas and combustion products. In an ordinary gas boiler, very hot combustion products go into the chimney, which are released into the atmosphere through the chimney. A certain percentage of heat is lost because steam leaves along with the gases.

First of all, this is a tank for collecting condensate, into which the condensate enters through a separate drain.
Burner – regulates the supply of air and gas.
Management control system.
The heat exchanger is a part of the boiler that is made of acid- and corrosion-resistant materials (acid-resistant steel, aluminum-silicon alloy), because condensate is a light acid. Some models use main and condensing heat exchangers.

Performance Benefits of Condensing Boilers

A gas wall-mounted condensing boiler, like a floor-standing one, has a number of positive properties:

almost silent operation. The design features of the boiler help eliminate noise effects, which is very convenient when using it inside a living space;
maximum power is achieved at low heating temperatures;
environmental friendliness and long service life. Thanks to high-quality materials, the service life of such boilers is 2 or more times longer than the service life of conventional gas boilers. And new burner design technologies significantly reduce the amount of harmful emissions;
efficiency due to the possibility of modulating the boiler power. The savings compared to traditional analogues are approximately 10%.

This is not all the advantages of condensing gas boilers, however, these are its main positive characteristics who will guide you and help you make your choice.

Wall-mounted condensing double-circuit gas boilers, like single-circuit ones, are used either in conjunction with a heated floor system, or for radiator heating.

Disadvantages of condensing boilers. Main Components

Naturally, like any other technology, they have condensation disadvantages. Condensing boilers, disadvantages:

price. Condensing gas boilers are on average 50% more expensive than conventional gas boilers;
the need to install a separate condensate tank. In these boilers, condensate cannot be drained into a septic tank, because it will immediately kill all bacteria in the septic tank. Therefore, you will have to install a special tank of a certain volume;
ineffective at very low temperatures.

These disadvantages of condensing gas boilers should definitely be taken into account before purchasing and installing them. Before purchasing, you need to find out what a condensing gas boiler is, the principles of operation, and, already knowing all the pros and cons, you can make your choice either in the direction of efficiency or in the direction of quality and efficiency.

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Everyone strives to save energy: car manufacturers, household appliances, windows and doors. Engineers are working on technologies that can keep the house warm...

Operation of traditional gas boiler entails some loss of thermal energy along with combustion products. To others negative point the formation of chemically aggressive condensate occurs, which causes corrosion in the system.

A condensing boiler cools the combustion products below the condensation point. The result is condensation of water vapor with the release of latent energy to the coolant, which is heated in the boiler.

Operating principle of condensing boilers

When gas is burned in condensation-type boilers, the effect of the formation of high-temperature water vapor occurs. The released vapors are concentrated in the form of a liquid on a heat exchanger made of of stainless steel. Standard types of gas heating equipment steam is removed along with other waste combustion products through the chimney.

When steam accumulations form on the primary heat exchanger, heat is released which is returned back to the heating system. This principle of operation of condensing boilers ensures high efficiency and operational efficiency of the entire heating system.

Features of operation

Condensing-type boilers are devices with closed combustion chambers. Waste products are discharged outside by force. Moreover, they all have minimum temperature. The presence of an additional heat exchanger makes it possible to increase the resistance to the passage of substances formed during the combustion of fuel. This operating principle makes the effect of natural draft impossible. That is why a condensing gas boiler operates on the principle of forced draft.

Condensing boilers have closed camera combustion with exhaust gas removal using special turbines. This has its advantages, since combustion products can be discharged to any place outside the heated building, moving along the supply and exhaust channels.

A condensing boiler can be installed in houses without a chimney. This solution is safer than the operation of traditional gas boilers, since the combustion process is completely isolated from the room where the heating unit is installed.

Application

Wall-mounted condensing gas boilers, like floor models They are used mainly in radiator heating systems or when it is necessary to install heated floors.

A prerequisite for creating the condensation effect is maintaining a certain water temperature in the return line. It is important that the coolant remains colder temperature, at which condensation forms. Subject to this condition the condensing gas boiler will produce maximum power work throughout the year.

Efficiency

How to achieve the highest efficiency levels when operating a condensing boiler? Compared to conventional gas units, condensing units are designed to utilize heat from condensation. Thanks to this, it becomes possible to achieve the coefficient indicators useful action at a level above 100%.

In the case of natural gas combustion in standard heating boilers, the wasteful consumption of thermal energy, which could be used beneficially, is about 11%. Assuming that thermal power boiler as a result of fuel combustion is 100% and adding 11% latent heat to this indicator, you can achieve a thermal power output of 111%.

To obtain high efficiency values when operating a condensing boiler, it is recommended to connect the heating unit to an external ambient temperature sensor. This makes it possible to maintain a stable level of return water temperature at the required level for effective application condensation effect.

Safety

Due to the effect of preliminary connection of gases and air in the corresponding burners, the wall-mounted condensing boiler produces minimal amount harmful substances from waste combustion products.

If we draw a parallel with traditional boilers, then the reduction in the amount of CO and NOx is from 80 to 90%. It is for this reason that recently in highly developed countries, as heating devices Condensing units are increasingly being used.

Advantages

Condensing heating boilers are newest word in the field of development innovative technologies. A profitable solution For the consumer, such devices become available due to a noticeable reduction in fuel consumption. Currently this technology It is considered one of the most economical for heating premises. Reduced gas consumption throughout heating season here it is about 35%.

Achieving such impressive results is possible thanks to the following factors:

the occurrence of the process of heat transfer from condensation both in heating mode and in heating water for domestic needs;
high efficiency indicators;
the ability to achieve a comfortable temperature for living in the absence of significant heat loss;
availability wide possibilities for flame modulation.

Today, gas burner equipment is represented by a large number of units. There are several types of heating boilers, each of which has its own advantages and disadvantages.

Electric boilers are easy-to-install structures, for the operation of which there is no need to supply gas to the house. At the same time, the cost of operating such equipment is higher than gas-powered models.

Liquid fuel boilers – great alternative electric models. They are ideal for heating rooms without gas supply. However, most models of this type are equipped with two burners for liquid fuel and for natural gas, which makes them universal equipment.

Today, condensing boilers, the operating principle of which is distinguished by innovation and technical advancement, are gaining increasing popularity. They appeared on the market relatively recently, but managed to conquer their niche, in which their sales volume is steadily growing. Let's take a closer look at what the peculiarity of condensing boilers is.

The operating principle of traditional heating equipment is quite simple. Heat exchange surfaces allow hot smoke to pass through, thereby transferring some of the energy to the coolant. Through the smoke exhaust unit, combustion products are discharged to the street. The efficiency of such systems is not high enough, since the water vapor that is formed during fuel combustion is removed along with the gases. A standard boiler is not able to transfer this energy to the coolant, while condensing technology is capable of doing this. Smoke is emitted through a special coaxial chimney.

Such units are equipped with a fan that blows air at a variable speed. This allows automation to select necessary conditions to create the most effective mixture air and gas. Condensation individual boilers Most of them are able to operate on liquefied gas, which is very important for regions with undeveloped infrastructure.

Condensation technology does not always work with maximum efficiency. To minimize heat loss, steam condenses in the boiler. The efficiency of such a unit increases with decreasing temperature regime heating system. This is why condensing boilers are best choice for floor heating. In this case, the coolant temperature will be about forty-five degrees.

The purchase of such an innovative boiler is advisable to increase the ease of use of the heating system, since the equipment is capable of operating at low temperatures. In addition, such units can reduce fuel consumption by 20%. To understand their advantages in comparison with traditional equipment, it makes sense to compare specifications conventional and condensing boilers, the operating principles of which are very different.

Standard gas unit It functions as follows: fuel combustion occurs in a special chamber, gases pass through a special heat exchanger, giving off energy to water, which plays the role of a coolant. Then the gases go outside through the exhaust circuit. Energy is lost along with water vapor, which is always formed during gas combustion.

In turn, a condensing boiler is able to extract additional energy from this steam and leave it in the system, thereby increasing its efficiency.

The main difference between a conventional and a condensing boiler is that the second is equipped with a special heat exchanger large area. Due to this, the smoke is cooled more efficiently, and its temperature can drop to forty degrees. Of course, this is not possible in a traditional boiler. The vapor contained in the smoke becomes liquid coolant. Some of the energy that is lost in a standard boiler remains in the system, increasing its efficiency.

Today there are many design variations of condensing boilers. In particular, there are models that are mounted on the floor or fixed to the wall. Single- and double-circuit units are also distinguished. This variety allows the buyer to choose the ideal technical solution to meet their specific needs.

Condensing boilers: operating principle

The steam cools in the unit, causing it to condense and at the same time transfers part of the thermal energy to the coolant. If in a traditional boiler a change in the state of aggregation of steam is undesirable, then in a condensing boiler this phenomenon is the most important stage heating the room.

Speaking about such a gas burner, it is worth highlighting its main advantages:

The efficiency of a condensing heating boiler reaches 108-109%. In this parameter, they are significantly superior to traditional gas burner equipment.
The amount of fuel consumed is twenty percent less compared to a traditional unit with comparable technical parameters. Modern innovative burners play an important role in fuel economy, as they create optimal ratio gas and air in a mixture.
Savings on the chimney are achieved through the use of more affordable plastic structures. This became possible because the temperature of the gases discharged from the boiler is quite low and is about 40 degrees.

The efficiency of using additional thermal energy of condensate depends on the temperature of the coolant at the entrance to the system - the lower it is, the greater the condensation effect can be obtained. Today, manufacturers of such equipment strive to ensure maximum condensation at any coolant temperature. To solve this problem, engineers focus on the dew point temperature.

When is it advisable to purchase a condensing boiler?

Today, condensing boilers are combined with both a floor heating system and conventional radiators. The degree of condensation and the temperature of the coolant in the return line are inversely proportional quantities. By installing a condensing boiler with underfloor heating, you can count on even more efficient operation equipment. The return water temperature will be noticeably lower than the dew point, which has a positive effect on the efficiency of the heater.

It is obvious that condensing boilers today are a worthy alternative to standard gas-burning equipment. Correct calculation of all indicators and correct approach to equipment installation guarantees high system efficiency and comfortable conditions accommodation in the cold season.

Regular heating boilers taken from combustion products most thermal energy and reduce their temperature (which averages 200 degrees) to 150-160 degrees. They do not cool below this mark, because this can not only reduce draft, but also initiate the appearance of chemically aggressive condensate, which sooner or later will lead to corrosion of heating equipment elements. But a gas condensing boiler is different in that the combustion products here are cooled below the dew point (that is, the indicator at which steam turns into dew - for those inherent in gas combustion, this is about 58 degrees).

Because of this, the steam condenses and gets rid of the so-called latent energy (heat released/absorbed during a phase change) in favor of water heated in the heating device. Consequently, in condensing-type boilers, heat is recovered (the energy that was wasted is returned for another use) and is released in the process of steam condensation. And if compared with conventional boilers, then in them this energy disappears along with the steam

Manufacturers and prices of condensing boilers

Before choosing a particular gas condensing boiler, check out the range presented on modern market. It is also important to know whether there are service centers for a particular company in your region. Despite the fact that there are most German models on the market, in fairness we will take a look at the most popular brands.

Table - Comparing popular manufacturers

Name	Manufacturer country	Characteristics	Average market value, in rubles
		For a house up to 350 sq.m. A model with a power of 31 kilowatts is quite sufficient. The equipment is designed for low gas pressure - no more than 5 mBar.
	Germany	Compact and productive equipment. So, to heat water at a rate of 14 liters per minute, you will need a boiler with a capacity of 32 kilowatts.	From 110 to 160 thousand
	Germany	Boilers and boilers in one shell. Cost-effective, ability to operate in several modes, compact (to install the device you only need 50-100 centimeters of free space).	Over 150 thousand
	Germany	Good economy class boilers. Built-in electrical modulation of the flame; heating and hot water supply.	From 90 thousand

As you can see, there is a choice. But in the end, the winner will be the manufacturer who presents efficient equipment at an affordable price. Yes, condensing boilers are still expensive, but this is just the beginning. And their savings today are quite good - from 15 percent.

Gas condensing boilers Buderus Logamax plus GB072

Name	Power, kWt	Description	DHW at T=30C	Dimensions HxWxD, mm	Price
Logamax GB072-14	2.9-14.0	single-circuit	—	840x440x350	RUB 78,480
Logamax GB072-24	6.6-22.5	single-circuit	—	840x440x350	RUB 82,730
Logamax GB072-24K	6.6-22.5	double-circuit	12	840x440x350	RUB 87,120

Features and principle of operation

The described devices are capable of providing thermal energy to auxiliary branches - for example, a “warm floor”. Moreover, their service life is twice as long as that of conventional models, and their configuration and performance ranges are many times wider. The power of boilers directly depends on the type of installation:

if the device is floor-standing, then up to 35 kilowatts;
if mounted, then up to 100 kilowatts.

We have already found out why the efficiency of traditional heating devices is quite low, as well as the reasons for the appearance of condensation inside the housings. But it is worth noting that if we talk about individual components of any boiler, then the main element in any case is the heat exchanger. In traditional models there is one, while in condensing models there are two. Moreover, they can be:

combined (two stages);
separate.

In this case, the first heat exchanger functions in the same way as in conventional heating devices. The thermal energy generated by burning gas heats the surface of the exchanger, passing through it, and the working fluid moving through its internal cavities. By the way, the temperature of this first heat exchanger never drops below that same dew point. But the second heat exchanger is heated by the same gases, but the working fluid flowing through it comes from the “return”.

Now pay attention! Temperature working fluid on the “return” branch lower than on the supply branch. Consequently, steam will necessarily condense on the walls of the heat exchanger. Well, here, as noted above, hidden energy “comes into play.”

In other words, when a substance changes its state from vapor to liquid, thermal energy is always produced. A physical law, to say the least. For this reason, the efficiency indicator of condensing devices exceeds that of traditional ones.

But don't forget one thing important point: what to do with negative impact moisture formed on the surfaces of the second heat exchanger? According to experts, there are two possible options here.

If the exchanger is made of cast iron or steel, then it should be coated with silumin (this is a special silicon + aluminum alloy).
Another option is to make a heat exchanger from stainless steel.

Video – Vitodens condensing boiler

What happens to the condensate?

This question is asked by many people planning to buy a gas condensing boiler. The body of this device is equipped with a small reservoir, where, in fact, condensation accumulates. From this reservoir it enters sewer system. By the way, in the European Union it is prohibited to pour such liquid into the sewer. There, each consumer is obliged to dispose of condensation moisture at his own expense.

And how much condensed moisture appears, for example, in 24 hours? If, say, we are talking about a floor-standing boiler with a capacity of 30 kilowatts, then it will produce about 30 liters per day. The volume is quite large, which is why in Europe it is prohibited to drain this water into the sewer. But note that some modern models are equipped with a built-in neutralizer - another tank filled with potassium and magnesium granulator (these are known to be alkali metals). And when condensate (and there are acids in it) passes through this medium, then chemical reaction. As a result, by-products (water and carbon dioxide) appear, and even in Europe such water can be poured into the sewer system.

Now let's briefly talk about the maximum performance of condensing boilers. If you purchased one such model, but at the same time left the old heating network without radial wiring, then do not say later that there is no saving. The fact is that the device will function effectively only when warmed up, but in the future everything will happen “as before.” For this reason, experts recommend changing the system wiring. This is the first point.

The second is the difference in temperature indicators at the input/output of the device (it should be at least 55 degrees). At the same time, the optimal temperature of the working fluid at the outlet should be 82 degrees. And this is when we are talking about the natural circulation of fluid in the system.

Classification

As noted earlier, according to the installation method they can be of two types:

floor;
wall-mounted

And depending on their functionality, they are divided into two groups:

for one circuit (designed for heating only);
for two circuits (respectively, heating + DHW).

The gas condensing boiler is compact and quite easy to install and operate, but there are certain limitations in terms of power (for most models it is 120 kilowatts). Wall-mounted two-circuit devices can be used not only in private houses, but also in apartments.

But do not forget that many devices are designed more for heating liquids, so if there is a constant need for hot water It is more advisable to install a boiler.

The power of floor-standing devices for one circuit is noticeably higher, so they are used to heat not only private houses, but also various complexes and industrial facilities. We also note that for supply hot water you need to install optional equipment– for the boiler to operate efficiently and smoothly, it should be operated in tandem with a water heater. Such devices are inexpensive, and their performance is quite high.

Note! Some models are equipped with replaceable burners, allowing you to use liquefied gas. Moreover, there are boilers that operate exclusively on liquid fuel - these are best option for non-gasified regions of the country, but the costs will be somewhat higher.

To be fair, we note that since 2004, condensing boilers have been produced that consume solid fuel. They are intended for houses where heat consumption is insignificant, or for heating industrial buildings, since the return temperature should not exceed 30 degrees. To increase power, pair operation of boilers or the combination of more devices was provided. The fuel here is pellets, which we talked about in one of the previous articles.

Fuel combustion safety

In the described boilers, the combustion chamber is closed, and the removal of combustion products is forced. And the temperature of combustion products, as we have already found out, is low, and due to the presence of a second heat exchanger, the resistance to their passage increases. Because of all this, it is impossible to use the usual draft using a chimney; therefore, combustion products are removed forcibly. For this purpose, there is a special turbine for air supply and removal of smoke gases.

A gas condensing boiler has all the advantages that other devices with a closed combustion chamber have:

safety - fuel combustion is completely isolated from the room;
no need for a chimney - smoke gases are removed through a special channel; this allows such boilers to be installed even where there is no chimney or where one cannot be installed.

This channel is output through external wall or above the roof level. According to the manufacturers, the ducts must be of the same brand as the boilers. Although it is quite possible to use products from other manufacturers, if they are selected correctly. If the channel is horizontal, then it should be made with a slight slope towards the heating device. This is the only way the condensate that appears in the channel will drain into the equipped tank, and not out.

Main advantages

The use of the described equipment is becoming increasingly profitable in our country. The heating season is about 200 days a year. And most low temperature air, taken into account when choosing a boiler (this is minus 20 degrees), is present for only 6-10 percent of this period.

Boilers consume approximately 15 percent less fuel than traditional devices. And if compared with old equipment, the savings can even reach 30 percent! But the use of such boilers is not only a material benefit, consisting in a more economical use of gas. They don't harm environment: due to high efficiency, gas consumption is reduced, and as a result, emissions are reduced various kinds gases leading to greenhouse effect. The degree of pollution in this case is even lower than strict European standards regarding the emission of carbon and nitrogen oxides.

Flaws

Yes, condensing boilers are more economical, you can’t argue with that. But you will have to pay dearly for such savings - such devices cost much more than traditional equipment. The payback period is directly related to the thermal energy needs of the building, the type of heating system, area, etc. Therefore, you are obliged to analyze the feasibility of purchasing such a boiler specifically for your case.

Rules for installing and operating a condensing boiler

If the boiler is installed correctly, its use will be in no way inferior to the use of standard gas appliances. But some parameters of condensing gas boilers should be given Special attention. So, the main difference, as we have already found out, is the need for waste disposal and the arrangement of a special drainage channel. Of course, in Russia it can also be poured into the sewer, but only in a diluted form (ratio 25:1). In other cases, neutralization units are used, in which the above reagents neutralize the aggressive liquid. And there are no inconveniences in operation, since the unit will have to be replaced a maximum of two or three times during the entire period of use.

Note! When calculating the heating system, it is necessary to take into account the optimal temperature of the heating device. To make operation extremely efficient, you can use old panel-type radiators as heating devices. A “warm floor” system can also serve as a source of heat.

Of course, a gas condensing boiler produces low-temperature combustion products, which is why the draft will be quite weak. Therefore, naturally, these products will not be able to rise up the chimney channel. In this regard, boilers are equipped with combustion chambers closed type, and the outlet channels are equipped with special turbines.

How to make a chimney for a gas boiler

Previously, we talked about how to make a chimney for a gas boiler on your own, and looked at the necessary standards and requirements. In addition to this article, we advise you to read

By the way, it is for these devices that they are installed coaxial pipes, that is, “pipe in pipe.” One of them supplies air from outside, and the other removes combustion products from the system.

Note! Condensation will in any case appear inside the chimney, so the material from which it is made must be acid-resistant steel. This point is mandatory and has no exceptions.

Alternative side of the issue

As we have already noted, an efficiency that is equal to or greater than 100 percent is a marketing ploy. But manufacturers of such equipment are still trying to get as close to this indicator as possible. At the same time, do not forget that it – an indicator – depends on the series important factors, among which:

the ratio of the volume of the room to the power of the heating device;
“age” of the device itself;
what type of ignition is used - modern or one of the old ones.

On this moment Manufacturers produce such boilers in two variations:

with wet heat transfer;
with dry

The first group includes devices used in residential buildings, or, more simply put, ordinary heating boilers. But the devices of the second group are used in commercial boiler houses and are still at the development stage. Their efficiency is higher, but they cost several times more.

What are the benefits of condensation?

In all devices used in private homes, power is adjusted by changing the fuel supply to the burner. And the devices described here are practically in no way inferior to traditional boilers, although their maximum efficiency is noted at lower temperatures. This is the difference, but that's not all.

Does the temperature of the working fluid depend on the power of the heating device? The higher the power, the more gas is consumed and, in turn, the higher the temperature of the working fluid (and vice versa). In most cases, the efficiency, as well as the efficiency of the boiler, depends on the gas supply (the principle “more is better” applies).

In the case of condensing type boilers, everything is somewhat different. Their maximum efficiency is noticeable even when the device is loaded to a third of its capacity. Therefore, here you should not choose among models of higher or lower power, since this parameter has no meaning.

The principle of operation of a gas boiler

That the heating system running on natural gas, is the most economical and effective way space heating, many people know. But what’s strange is that the use of gas seems to suit everyone today, but high and stringent energy consumption requirements set certain restrictions. Therefore, condensing boilers occupy a special place in the heating equipment market. By the way, in some European countries the law prohibits the use of other types of heating gas appliances, except condensing ones. Let's try to understand gas condensing boilers, the principle of their operation, advantages and disadvantages.

Principle of operation

First of all, we will be interested in the operating principle of this type of boiler. To show how it differs from conventional units, it is necessary to understand the operating features of the latter.

What's going on in them?

Gas as fuel is supplied through the burner to the combustion chamber, where it is burned. In this case, the released thermal energy heats the metal heat exchanger in which the coolant moves.
Giving up part of the thermal energy, the flue gases pass into the chimney and are discharged through it to the street.

It would seem that it could be simpler. But there is one very important nuance. In order for the draft in the chimney to be appropriate and condensation not to form or accumulate in it, it is necessary that the temperature of the flue gases drops from 200C to 140C. That is, there should be an intensive release of thermal energy to the heat exchanger. But take into account the fact that the temperature of the exhaust gases should not be lower than this level.

In fact, a temperature of 140C is quite a serious potential, which simply evaporates into the atmosphere. The thermal energy contained in the exhaust gases is not spent for its intended purpose. Moreover, inside the flue gases there are always moist air vapors, which also have a certain temperature potential. That's why condensing boilers were invented, in which all these nuances were collected and used.

Moisture collects inside the gas condensing boiler, which, when condensing, releases part of the energy used to heat the additional heat exchanger.

Device

So, it is clear that the design of a condensing gas boiler has two heat exchangers. The first one works according to the standard principle, that is, it is heated by combustible fuel. It is here that the main selection of thermal energy occurs. The second, which is called condensation, takes away the secondary energy of condensed moist air vapor.

The design of a condensing heat exchanger is quite complex. After all, the temperature of the exhaust gases and condensate is not very high, so care must be taken to remove as much heat as possible.

There are a few technical solutions that help achieve the desired result:

Increasing the temperature sampling area. To do this, fins in the form of spirals are welded to the heat exchanger.
Internal cavities with different sections are used. This allows for intensive selection thermal energy by reducing the volume of coolant flow passed through.
A secondary heat exchanger is installed on the return circuit of the heating system. In this way, rapid condensation of wet vapors from exhaust gases is achieved by reducing the dew point. It turns out that the coolant enters the heating gas boiler already heated. And this affects the reduction of fuel consumption and the efficiency of the unit itself.

If we consider the operating principle of this type of unit from the perspective of a traditional boiler, then a kind of recovery occurs in it, which is usually used in air conditioning systems of buildings.

I would like to add that manufacturers install only high-tech burners in the design of a condensing gas boiler, with the help of which optimal mixing of main gas and air is achieved. This again increases the efficiency of the gas apparatus.

Pros of a condensing unit

Wall-mounted gas condensing boiler Buderus

What does all this lead to when comparing traditional and condensing gas boilers?

The fuel consumption efficiency of a gas condensing boiler is 20% higher than that of a traditional one.
Blowout carbon monoxide and other combustion products are reduced by almost 70%.

That's what's surprising. The principle of operation of the boiler and its design were invented about a century ago. But only now its use has become possible. The fact is that the metal components and structures of the device could not withstand for long the serious loads associated with the process of condensation of wet vapors and high temperatures.

Currently, these problems have been solved through the use of corrosion-resistant materials in boilers. After all, the resulting condensate is a chemically active substance, which short term action disables any durable materials. Therefore, boilers of this model use either stainless steel or silumin - an alloy of aluminum and silicon.

If we talk about the external differences between the two models, then it will be difficult for an inexperienced person to do this. But condensing gas boilers are wall-mounted units with a closed combustion chamber. Anyone who has an idea of what we are talking about will understand how many advantages are added only due to these two indicators.

The real state of affairs

Boiler structure

So, condensing gas boilers are more economical - there is no dispute here. But you will still have to pay at least once for this savings. These models are one and a half times more expensive than traditional ones. This is the first.

Second. I would like to draw your attention to some positions that are not striking at first glance. And even some experts do not always pay attention to them. For example, a condensing boiler is wall option- in terms of power, it is in the range of 20–110 kW. Traditional wall-mounted units have more modest performance - up to a maximum of 36 kW.

Can you imagine that small sizes condenser double-circuit type capable of providing large amounts of heat and hot water for household needs a private house? Eg, with total area 800 m². If you use a traditional heating unit, then only the floor type.

Based on this, you can compare the cost of the two models. It almost levels out. But there are advantages condensation models much more:

Fuel economy.
Reducing harmful emissions into the atmosphere.
Efficiency of equipment operation.
In addition, there is no need to allocate separate room for organizing a boiler room, as is usually the case with floor-standing units.

The most important thing is that the efficiency of the device depends on how intensively it is used. After all, the lower the temperature of the coolant in the return circuit, the more complete the condensation in the secondary heat exchanger, the more thermal energy is released, and the higher the efficiency of the equipment becomes. This is why this type of heating device is more cost-effective in so-called low-temperature heating systems - heated floors as an example.

Gas boiler diagram

But in reality, Russian operating conditions are completely different from those in Europe. For example, when the temperature outside the window is minus 20–50C, it is necessary to increase the temperature of the coolant. This can be done only by increasing fuel consumption, because the main source of thermal energy is burned gas. This means that the temperature of the coolant in the return circuit will not drop below 60C. With this indicator, we cannot talk about condensation of wet vapors. That is, the condensing gas boiler you installed begins to work like a regular one. So is it worth purchasing such an expensive device?

However, we will not diminish the advantages of condensation models. Even when operating in this mode, they are more economical than traditional ones. True, at first glance, the savings are not very large - up to 5%, but if you recalculate the annual gas consumption, the amount will be impressive. In addition, the boiler is designed in such a way that even with a maximum drop in gas pressure in the pipe line, it will continue to operate. Efficiency, if it falls, will be insignificant.

Conclusion on the topic

Someone who considers himself a frugal person and keeps his expenses family budget wearing tight gloves, you should purchase a condensing gas boiler for heating and hot water supply own home. With the help of such a unit, you can save a lot on fuel consumption without reducing such an indicator as efficiency. Moreover, gas prices are rising every year.