Which gas boiler is economical? Which wall-mounted gas boiler is the most economical? Design features affecting efficiency

When choosing an economical gas boiler at home, every consumer is absolutely right to look at its passport with technical characteristics. But high efficiency, and even more so the power of the device, will not always guarantee that heating costs will decrease and conditions will become more comfortable. It is imperative to take into account the heated area, but not only in order to calculate the boiler power, although this is also important. If you choose a powerful and economical boiler for a small house, it is unlikely that it will actually turn out to be so, since in order to maintain the set temperature, it will turn on and off more often, which will lead to the loss of some heat.

The next point concerns the operation of double-circuit boilers, which provide the house not only with heat, but also hot water. In this case, there are no objective losses for gas, but there are for heat. Due to the nature of the operation of such devices, when selecting hot water Heat production stops and, accordingly, cooling of the coolant begins. In this case, residents of houses with a large heating system will feel the inconvenience less noticeably, since the coolant travels a longer path before returning to the boiler. If the heating system is short, then the coolant returning to the heat exchanger will not receive heat, which means the room will become cooler.

When choosing a boiler, it is important to pay attention to the type of firebox: open or closed. The former are mainly represented by floor-standing models. Closed boilers use a forced convection air supply system that can be adjusted. In open fireboxes, the atmospheric supply principle is used. But the opportunity automatic regulation significantly increases the efficiency of the latter, especially if sensors are connected to them that monitor the temperature outside and indoors.

In models with a closed chamber of a turbocharged type, the principle of regulating the intensity of combustion or its smooth switching to lower power is used. Consumers also appreciated another advantage of these boilers - the ability to install a coaxial chimney. It differs from a traditional device for removing combustion products in that it is discharged horizontally, through outer wall, and not vertically, onto the roof.

A type of turbocharged boilers are condensing boilers, with a closed circuit heat exchanger, which is located cylindrically around the burner. In these models, it is possible to return to the system the energy that is lost through the evaporation of water vapor, that is, in this case, the steam itself works for the benefit of the heating system of the house, allowing the boiler to achieve 96-98% efficiency.

How to choose the right economical gas boilers

Of course, receiving any information from friends, from the Internet and magazines helps to form an opinion among a consumer who is busy purchasing a gas boiler for heating a home. But it is best to turn to professionals.

Our company “Alfatep” presents models from all leading manufacturers of gas boilers: European, Russian and Korean. Therefore, choosing equipment with characteristics that are ideally suited to the conditions of each home is not difficult. There is a choice of both wall-mounted compact models and floor-mounted ones, with which you can heat large houses. Widely represented and double-circuit boilers, especially relevant for use in houses without hot water supply.

German boilers are represented by well-known brands Vaillant, Bosch, Buderus, Viessmann, characterized by reliability and functionality

Among the Italian Baxi models, you can choose not only a device that can provide heat to your home, but also one that is as convenient as possible to manage and operate. Many models are equipped with remote control panels with temperature sensors built into them.

You can give your choice to other “Europeans”, for example, the French brand DeDietrich or boilers from Slovakia - Protherm, represented by the widest possible range of models.

We also have Korean developments, represented by the brands Navien, Rinnai and Kiturami, with automatic control and compactness.

The domestic manufacturer offers boiler models under the Lemax brand, represented by models in several series. For noticeable savings you can choose a model from the “Premium” series for your home, in which, in addition to using modern technologies for gas combustion, care is taken for the consumer in terms of ease of use of the equipment.

By contacting us, any branch of the Alfatep company, or going to the online store website, you can get any advice on choosing a gas boiler for heating your home. When purchasing, we provide an additional service for delivery of goods to the site, as well as installation and connection of equipment, which is carried out by our specialists quickly and efficiently.

Fewer and fewer people are willing to pay extra money for the increased energy consumed when heating a private house or apartment. Hence the demand for economical gas boilers designed to replace the old ones heating units or take place in the boiler rooms of new buildings.

But try to figure out which boilers are the most economical and how to choose the right model among them. Homeowners often fall for the bait of unscrupulous sellers and buy more expensive body generators. In the publication we will give explanations about the efficiency of gas boilers; study them before going to the store.

What does profitability depend on?

An ideal gas heating boiler must first effectively burn main or liquefied gas, and then use all the resulting heat to heat the coolant for the heating system. In reality, not everything is so smooth, and here's why:

1. For efficient combustion of fuel and production maximum quantity heat, you need to mix gas and air in precise proportions (approximately 1: 10). Not every heat generator can do this.
2. During the combustion reaction, methane is released carbon dioxide and simple water, which immediately evaporates, taking away part of the thermal energy of the burned fuel.
3. A priori, heated combustion products cannot transfer all the energy to the coolant; some of it will still fly out into the chimney. The size of this part depends on the design of the heating unit.

The efficiency of Atem non-volatile double-circuit boilers with an open combustion chamber is in the range of 86...88%

It turns out that one part of the energy contained in the fuel is lost during the combustion stage, and the other part is lost during heat transfer. The smaller these losses are, the more rationally the fuel energy is used and the more economical the gas boiler for the home is. The efficiency of the heater is characterized by its efficiency specified in the technical data sheet for the product. The higher this indicator, the more heat the heat generator directs to heat the coolant and the more economical it uses natural gas.

The efficiency of modern gas boilers depends on their design and ranges from 85 to 96%. The higher efficiency figures announced by heating equipment sellers do not correspond to reality.

Evaluating the efficiency of different heaters

When choosing, the task is somewhat broader than just choosing the most economical gas boiler. It is important that it matches the conditions of your country house or apartment and approached the heating system. Solving the problem is impossible without understanding what types of heat generators exist and how they differ from each other. There are currently 3 types of gas-using units offered on the market:

• atmospheric, with an open combustion chamber;
• supercharged (otherwise turbocharged), with a closed combustion chamber;
• forced condensation.

Wall-mounted (left) and floor-mounted (right) model of a gas heater

The listed varieties are produced in execution. Only among atmospherics can you find so-called parapet (wall) models, with a side chimney opening horizontally through the wall onto the street. There are double-circuit modifications of boilers designed to provide hot water to 2-3 consumers in a private home.

Floor or wall mounting does not in any way affect the power or efficiency of the gas boiler. Only the design and operating principle of the heat generator matters, so each type should be considered separately.

Units with an open combustion chamber

These gas boilers cannot be considered the most economical, since their efficiency rarely exceeds 85%, and the temperature of the gases at the outlet into the pipe reaches 150 ° C. The reason lies in in a simple way combustion of fuel with free air supply from the room where the unit is located. When there is an excess of air in the air-fuel mixture, not the best Better conditions combustion, which negatively affects the efficiency of the heater. A high temperature of combustion products indicates insufficient heat exchange and heat loss.

Scheme of a floor-standing atmospheric boiler with a cast iron heat exchanger

There is another point. Most burners installed in inexpensive aspirated units can operate in one mode. Simply put, to maintain the set coolant temperature, the burner is periodically turned on and off. This simplest algorithm works, but not the most economical. However, these boilers are very popular for the following reasons:

• the lowest price;
• independence from the presence of electricity in the house;
• simplicity and reliability of design, lack of electronics.

Note. Not all atmospheric boilers are energy-independent. There are many models different manufacturers, equipped with controls and operating from the mains. But from the availability of these funds Thermal efficiency the unit does not become higher.

Burners of floor-standing atmospheric boilers work in tandem with non-volatile automation

For a private house with open system no gravity-fed heating best option, how to choose an atmospheric gas boiler that does not require electricity. Even despite the relatively low efficiency. Such systems exist to heat private homes in areas with unreliable electricity supply. No one will think about saving money when a high-tech boiler stops during a power outage and the house begins to freeze.

Turbocharged heat generators

Diagram of a wall-mounted heat generator with forced air injection

The closed combustion chamber and forced air supply implemented in such units clearly improve the conditions for combustion of both natural and liquefied gas. Unlike atmospheric heaters, the following types of burners are used in forced-air heaters:

• two - and multi-stage;
• modulation.

The bottom line is that when the set coolant temperature is reached, such burners switch to a lower level of combustion intensity (first type) or gradually reduce power to a minimum (second type). That is, the electronic control unit of the gas boiler independently regulates the power of the burner device depending on the thermal load or the appearance of a request from the outside DHW systems. Hence the higher efficiency of a pressurized double-circuit boiler - 90-92%.

Judging by the reviews on the forums, wall-mounted turbocharged heating units occupy the first position in the field individual heating apartments But not at all because of the high efficiency, but thanks to the coaxial chimney, which is discharged horizontally through the wall to the street. This eliminates the need to install a traditional chimney or connect the boiler to a ventilation shaft, which is strictly prohibited by the rules.

Condensing boilers

Essentially, these are the same turbocharged heat generators with a closed chamber, only with a higher efficiency - up to 96%. It is achieved due to the closed design of the heat exchanger surrounding the cylindrical burner on all sides. In this way, it is possible to return and use the heat of vaporization taken during the combustion process. The released water evaporates when high temperature in the combustion zone, after which the steam condenses from contact with the heat exchanger and returns energy back.

A condensing gas boiler is a clear answer to the question of which is the best heat source to choose in terms of efficiency. Provided that your Vacation home is supplied with electricity without interruption or you have alternative source– block uninterruptible power supply or an electric generator.

Like forced-air heating units, condensing boilers cannot function without electricity.

Since these heat sources are high-tech, their price is quite high. This is the only significant drawback of heat generators; in other respects they are beaten only by electrical installations with an efficiency of 99%. Judge for yourself: the flue gases leaving the condensing boiler have a temperature of no more than 70 ° C, which indicates the lowest losses and best selection heat in favor of a water heating system.

Due to the condensation of water vapor, the heat generator effectively uses the heat of gas combustion

Which gas boiler is better to choose?

This section is intended to tie all previous discussions to real life, because theory and practice are different things. Theoretically, everything is correct, the most economical gas boiler with the highest efficiency is a condensing boiler. But after learning how much this miracle of technology costs, not everyone will dare to buy it. And is there such a need?

Take the same gravity system, which does not require pumps, automation and electricity. It is not advisable to buy an expensive heat source for it, although a turbocharged or condensing heat generator will cope well with such a system. It will simply force the coolant to circulate forcibly from its own pump. The question is the reliability of power supply and the decent price of equipment, which will pay off when it is unknown.

It is also not very reasonable to buy a condensing boiler for small house 100 sq. m of area with any heating system. In such an area, you are unlikely to feel the efficiency compared to an inexpensive aspirated engine. You can see a real difference if country cottage area over 300 sq. First, heat it with a simple boiler, and then change it to a condensing boiler.

Final Conclusion

When choosing a gas boiler, do not focus on efficiency, use common sense. If you don’t have a chimney in your house, take a turbocharged heat generator; if you have problems with electricity, use a non-volatile aspirated one. If you have a cottage on 2-4 floors, definitely install a condensing boiler. Cost-effectiveness can be achieved in other ways, for example, by simply insulating the building.

The cost of gas is less than other coolants, and if it is used efficiently, you can significantly save on heating. Economical wall-mounted gas boilers are popular among consumers, so companies are trying to create such units by reducing natural energy losses.

The main characteristic of any fuel is the amount of heat released during combustion. The most economical gas boilers are those that spend all combustion energy on heating the coolant, and its losses are minimized.

The combustion process involves gas and air. When heated, they react and produce carbon dioxide and water. The released energy goes:

• for heating the coolant;
• into the chimney along with combustion products;
• for water evaporation.

Economical gas boilers are designed so that the second and third components are kept to a minimum. Coefficient useful action of such heating devices varies between 90-99%.

Note! The lowest efficiency is for models with an open firebox, the highest is for condensing type models.

For gas boilers, the temperature of the exhaust gases should not exceed 150ºC. For condensing units this indicator is at 70ºC. If the gas temperature rises to 200ºC, then it is better not to purchase such boilers, as they consume a lot of fuel. Also important indicator is the amount of water vapor that comes out along with the smoke: for average boilers it is 6%, for condensing boilers it is 0.5%.

Based on the presented indicators, it is clear that condensing units are the most economical. They have a cylindrical stainless steel burner, around which a heat exchanger is concentrated, made in the form of a coil with closely spaced turns. Drops of steam condense on it, which transfer heat to the coolant. For conventional boilers, the heating circuit has simple form, as a result, the steam does not have time to condense and exits into the chimney along with the exhaust gases.

You can learn more about the design of condensing boilers by watching the video.

What to look for in order to choose the most economical gas boiler?

To choose the most economical gas boiler for your home, you should pay attention to the following characteristics:

1. Type of firebox: open and closed. Boilers with a closed firebox consume less gas.
2. Efficiency specified in the documentation.
3. Temperature of exhaust gases depending on operating mode.
4. The shape of the heat exchanger: the more complex it is, the more steam will condense during the combustion process.
5. Quality and thickness of the thermal insulation layer.

Please note that condensing units are more expensive than conventional ones. It is desirable that the model operate on main gas and liquefied gas. Although the second type of fuel will cost much more.

However, high-tech condensing boilers are not for everyone. In regions where power outages occur frequently, the best economical option is a non-volatile heating device model. After all, if the gas boiler stops working due to a power outage, no one will think about saving in the cold.

Note! Maintenance of a conventional boiler, for example, flushing the heat exchanger, can be done independently, but cleaning the condensing unit will require the help of a specialist.

Selecting burner type

The efficiency of a wall-mounted gas boiler also depends on what type of burner it is equipped with. The following types of burners are installed in closed combustion chambers: two- and multi-stage; modulation. The essence of the modulation element is that when the required temperature is reached, it switches to the minimum level. Electronic system control independently regulates the power of the burner depending on the temperature in the room or outside.

Units with a closed combustion chamber are popular not only because of their economically operating burner, but also because they are equipped with compact coaxial chimneys. They are cheaper than full-fledged classic analogues and are easier to install. Installing a conventional chimney will require more effort and official permission from the relevant services, which will not be needed when installing a coaxial pipe.

Life time

Economical gas boilers cannot have a short service life. They should work for at least 30 years, while conventional inexpensive units last 10-15 years. The period that the boiler can operate without breakdowns is also important. It usually depends on the overall service life.

Service maintenance

Many buyers of wall-mounted gas boilers, installing for the first time autonomous system heating, trying to save on the planned after-sales service. If you do not carry it out, you can save about 12,000 rubles per year, but on the other hand, there is a risk of the burner focus shifting, deviations in the operation of the automation occur, and carbon deposits form. At first glance, these errors are small, but they lead to a decrease in the efficiency of using the heat of the burned fuel, as a result of which the operating costs of the unit will increase.

How to reduce gas consumption in an operating boiler?

You can increase efficiency and reduce fuel consumption in an already purchased gas boiler if you use the following recommendations:

1. High-quality insulation of walls. If the house is insulated with modern thermal insulation materials, then the heat inside the premises will remain longer, and this will help reduce gas consumption.
2. Replace windows and doors or insulate them. Very often, the main sources of heat loss are poorly insulated windows and doors, especially if they have cracks or are installed incorrectly.
3. Some models of units have “auto” or “economy” modes. When they are turned on, the automation system will smoothly change the degree of heating. Using these modes you can save up to 10% fuel.
4. Install a temperature sensor on the gas boiler, which will change the settings depending on the temperature difference between inside and outside.

Models of economical wall-mounted gas boilers

ARISTON GENUS PREMIUM EVO 24 FF

The Italian condensing type model ARISTON GENUS PREMIUM EVO 24 FF has two circuits and has low gas consumption and high efficiency = 108%. It is also small in size and can easily fit in a small room, such as a bathroom or kitchen. The unit is equipped with an innovative 1:10 modulation, which can change the power. This ensures optimal temperature and maximum gas savings. With a power of 22 kW, the boiler consumes only 2.33 cubic meters. m of gas per hour.

Bosch Gaz 6000 WBN-24CRN

The double-circuit boiler of the German company Bosch Gaz 6000 WBN-24CRN is very popular among consumers. Although it is not a condensing unit, the unit has a fairly high efficiency = 93.5%. It only requires 2.7 cubic meters to operate. m of gas per hour at maximum power. This model is equipped with a closed combustion chamber and is suitable not only for heating a house, but also for an apartment.

Protherm Panther 12 KTZ

For heating small rooms up to 80 m², the Protherm Panther 12 KTZ wall-mounted gas boiler is ideal. Its power is 11.5 kW, which is enough to maintain heat even at very low temperatures. This model is equipped with a closed combustion chamber and has a record low gas consumption of 1.3 cubic meters. m per hour. It is compact in size and highly reliable.

To choose the most economical gas boiler for your home, you should carefully analyze the operating conditions of the future unit. Then you need to think about what characteristics it should have in order to use fuel economically in the current realities.

It is quite logical that every owner of a private home wants to save fuel, which is spent on heating the home. This also applies to natural gas, which is constantly becoming more expensive. The first step towards savings can be taken at the heating design stage, that is, choosing the most economical floor-standing gas boilers.

The principle of boiler efficiency

Ideally, a heating boiler must first effectively burn liquefied or natural gas, and then redirect the resulting heat to heat the coolant. But in reality, everything does not always go so smoothly, and for these reasons:

Thus, one part of the energy contained in the fuel is lost during the combustion stage, and the second part is lost during thermal transfer. The lower these losses, the more productively energy is consumed and the more economical the gas boiler is. The operating efficiency of a heating device is expressed in its efficiency, which is indicated in the manufacturer's instructions. The higher this characteristic, the more thermal energy is directed to heating the coolant and the gas is burned more economically.

Efficiency of modern gas equipment depends on the design of the boiler and is in the range of 80−95%. The more inflated power ratings indicated by manufacturers of heating appliances do not correspond to reality.

Selection of gas equipment

When choosing, the main task is much broader than simply determining which gas boiler is the most economical and reliable. It is necessary that the equipment meets the conditions of a private home and is suitable for the heating system. Solving this problem requires understanding what types of heat generators there are today and how they differ from each other. There are currently three types on the market gas-using equipment:

• pressurized condensing boilers;
• supercharged (turbocharged) with a closed firebox;
• atmospheric with open firebox.

The above types are manufactured in wall and floor versions. Only in atmospheric boiler models can you choose wall-mounted (parapet) products with a side chimney outlet that goes horizontally to the street through the wall. There are double-circuit varieties of boilers that are used as a boiler to provide hot water.

Execution in wall or floor-standing version does not affect the power and practicality of the boiler. The main importance is only the operating principle and design of the heat generator.

Atmospheric units

This gas equipment is not one of the most economical devices, since the efficiency does not often exceed 83%, and the temperature of the burned gas at the exit into the pipe is about 160 °C. The reason is the usual version of fuel combustion with a free supply of oxygen from the boiler room. When there is an excessive amount of air in the air-fuel mixture, bad conditions begin to be created. favorable conditions for fuel combustion, which negatively affects the efficiency of the heater. An increased temperature of combustion products indicates ineffective heat exchange and loss of thermal energy.

There is one more important point. Many burners that are installed in cheap atmospheric boilers can only operate in one mode. In other words, to maintain the temperature of the coolant, the burner is regularly turned on and off. This is the simplest operating principle, but not the most economical. But one way or another, this equipment is very popular for several reasons:

• reliability and simplicity of the device;
• lack of electrical components;
• independence from the availability of electricity;
• low cost.

Not all atmospheric equipment is energy independent. Exists a large number of models from various manufacturers that are equipped with automation and control equipment that consume electricity. However, their presence does not increase the efficiency of boiler equipment.

To heat a house with an open firebox that works naturally, it is best to install an atmospheric boiler that does not require electricity. Even despite the relatively low power of this equipment. These units are designed to heat buildings in areas with unstable electricity supply. In this case, we are not talking about savings if during a power outage the boiler stops working and the rooms in the house begin to cool.

Pressurized thermal generators

The closed combustion chamber and forced air circulation, which is implemented in these devices, improve the combustion conditions of liquefied and natural gas. In turbocharged boilers, unlike atmospheric ones, the following types of burners are used:

• modulation;
• two- and multi-stage.

The idea is that when the specified coolant temperature is reached, these burners switch to a lower level of fuel combustion activity (first type) or smoothly reduce the intensity of the combustion process to a minimum (second type). That is, the automated boiler control system itself controls the burner power, taking into account the thermal load or the signal from the DHW operation. It is for this reason that the efficiency of turbocharged boilers is 91-95%.

According to reviews, turbocharged wall-mounted gas boilers are in first place for individual heating of apartments. However, not at all because of the increased efficiency, but due to the coaxial chimney, which is horizontally discharged to the street through the wall. This allows you not to equip the chimney pipe, and also not to connect heating device to the ventilation shaft, which is strictly prohibited by SNiP.

Condensing devices

By and large, these are the same forced-air heat generators with a closed firebox, but with increased efficiency - up to 97%. This is achieved thanks to the closed design of the heat exchanger, which surrounds the cylindrical burner around the entire perimeter. Yes, we manage to return thermal energy vapor formation lost during combustion. The resulting water begins to evaporate at elevated temperatures during combustion, then the steam, after contact with the heat exchanger, condenses and transfers back thermal energy.

Condensing gas equipment is the most economical equipment for heating a private home. Provided that electricity is supplied to the area without interruption or there is an alternative power source - diesel or gasoline generator. Like turbocharged heating boilers, condensing equipment cannot operate without electricity.

Since these devices are more technologically advanced, their cost is quite high. This can be attributed to the only significant drawback; according to other characteristics, only electrical installations with an efficiency of 98% are more economical.

Installation benefits

Today, gas heating equipment is widely used in country dachas and in private homes. Ease of use, safety and convenience are the main reasons for its popularity gas heating. The boilers also have a number of other advantages:

The heat exchanger of floor heating equipment is made of high-quality and durable cast iron, providing best thermal insulation, and modern burners make it possible to operate the device simultaneously on liquefied and natural gas.

Besides, floor standing boilers react clearly to negative impacts external environment, their body is coated with special anti-corrosion compounds that prevent metal oxidation.

Main disadvantages

However, a gas heating boiler also has certain disadvantages. The main ones are the following:

In addition, despite the high safety of gas installations, their operation still needs to be monitored, since even minor interruptions disrupt the normal production cycle.

Theoretically, the most practical and economical gas boilers for heating a private home with maximum efficiency are condensing boilers. However, after learning the cost of this equipment, not every homeowner will dare to purchase it. Therefore, you can buy a conventional gravity system, which does not require electricity, automation or a pump.

It is also not very cost-effective to purchase condensing equipment for a small building with an area of ​​less than 150 square meters. m with any type of heating. In this area, the savings will not be noticeable, unlike the purchase of an inexpensive atmospheric boiler.

When choosing gas equipment, you do not need to focus only on efficiency; you must also be guided by considerations of necessity and expediency. If there is no chimney pipe in the house, it is best to choose a forced-air heat generator when there are power outages - a non-volatile atmospheric boiler. If the cottage has more than two floors, it is advisable to install a condensing unit. You can make a boiler economical in other ways, for example, by conventional insulation of the house.

Modern gas boilers are efficient equipment, in terms of efficiency it is inferior only to electric generators. But the level of efficiency depends on the presence of high-tech elements in their mechanism, and, accordingly, on the cost of the device as a whole. The same condensing units are as economical as they are expensive. At the same time, an ordinary inexpensive boiler can fully satisfy the needs of the homeowner.