Reliable and economical floor gas boiler. The most economical heating of a private house: the right choice of boiler and wiring diagram
Ecology of consumption. Manor: The desire of any homeowner to save fuel used to heat a private house is quite natural. In particular, this applies natural gas, which continues to grow steadily in value. The first step towards frugality can be taken at the stage of choosing a heat source, that is, purchasing the most economical gas boiler.
It is quite natural for any homeowner to want to save fuel for heating a private house. In particular, this applies to natural gas, which continues to grow steadily in price. The first step towards frugality can be taken at the stage of choosing a heat source, that is, purchasing the most economical gas boiler. How to make such a choice will be explained in our article.
What is the thermal energy of the gas used for?
Before you start choosing, you need to know a few important things about heating equipment. The natural gas that enters our homes through the mains must comply with the regulations and have a certain calorific value. This value shows how much heat is released when a unit volume of gas is burned. The task of the heating installation is to direct this energy as much as possible to heat the building. The better she does this, the higher the efficiency of her work.
For reference. In the post-Soviet space, it is customary to make calculations based on the lower or minimum calorific value of gas, its value is 8000 kcal / m3 (33500 kJ / m3).
The efficiency of the heat generator, or otherwise, - its efficiency is expressed as a percentage of the calorific value of the fuel. In simple words, efficiency value gas boiler shows what part of the heat of combustion of the fuel he manages to transfer to the house. The larger this part, the more fully the energy carrier is used, you pay less for losses, which means that efficiency increases. Between the two terms "efficiency" and "economical" you can put an equal sign.
A little about the process of burning natural gas. It is quite complicated, but we will not go into details, but will highlight the main substances formed as a result of the process. In the case when sufficient oxygen is supplied and created ideal conditions for combustion, carbon dioxide is released ( carbon dioxide CO2) and ordinary water. Now we list what the thermal energy of the fuel is spent on in the boiler plant:
- for heating the coolant;
- for losses with outgoing flue gases;
- for the evaporation of water formed during chemical reaction burning.
The most efficient and reliable gas boilers operate in such a way that the first item of energy consumption is maximized, and the other 2 are minimized.
How to determine the efficiency of the boiler?
Before giving specific recommendations on choosing an economical heat generator, let's clarify some points. efficiency modern installations burning natural gas lies in the range of 90-98%. The lowest rate is for inexpensive non-volatile models with a one- or two-stage burner device. Modulating burners work better with electronic control and forced air injection, where the power is regulated smoothly, and not in steps. But one must understand that the burner only burns fuel, and the transfer of heat is the task of other elements of the boiler.
Initially, the heat released in the furnace directly heats the water jacket of an economical gas boiler. The remaining part of the heat, together with flue gases, enters the steel or cast iron heat exchanger. This is one of milestones, it is here that the combustion products transfer part of the remaining energy to the water, after which they flow into the chimney. The share of heat that got there is irretrievably lost, leaving in the atmosphere.
How large is this proportion, shows the temperature flue gases, indicating the efficiency of the boiler. If the gas temperature at the outlet pipe of the unit is 200 degrees or more, then you have a not very successful design of the heater. It allows too much heat to escape outside. If the temperature of the combustion products is in the range of 100-150 ºС, then this boiler can already be considered as an acceptable option.
Most best performance according to the temperature of the flue gases, gas condensing boilers give out. This is realized by removing the heat of vaporization of water. In the previous section, we talked about how water released as a result of a chemical reaction evaporates, taking away part of the heat of combustion of natural gas. So, the most economical boilers are able to take this energy back by condensing the resulting water vapor.
For this purpose, the unit uses a cylindrical type burner installed inside the heat exchanger made of of stainless steel. The latter is a coil, where the turns are close to one another, and the coolant circulates inside. The steam has no other way but to pass through this coil and condense on its surface, giving off heat. The flue gas temperature of condensing heat generators is record low - from 45 to 70 ºС, and the efficiency reaches 98%.
Recommendations for choosing an economical boiler
Determining which gas boiler is the most economical is actually not difficult. These are the condensing units that are mentioned above. Another thing is that they cost a lot of money, like all high-tech devices. The availability of such an acquisition for many homeowners remains in question, so we take the liberty of giving general recommendations for the successful selection of the heating system. First, let's dispel one myth.
Sales representatives of some brands, offering condensing heat generators for heating, use one marketing ploy. Talking about the process of taking heat from water vapor, they declare the efficiency of the unit at the level of 109%. The rationale is this: the efficiency of a standard boiler is 98%, and due to condensation, another 11% is added to it. A simple calculation gives a result of as much as 109%. This shows the picture:
In fact, the efficiency can never be more than 100%, these are the basic laws of physics. After all, when fuel burns, it releases a certain amount of thermal energy. A small proportion of it is spent on the evaporation of water, and the boiler simply returns it back, preventing it from flying into the pipe. Ideally, its efficiency would be 100%, but no more. In practice, even the most expensive and economical gas boilers for a private house can give 98% on the strength.
When choosing a heat generator, you should ask for its technical passport and pay attention to:
- the efficiency value specified in the documentation;
- the temperature of the flue gases at different operating modes of the unit;
- heat exchanger design. The more moves inside it make the products of combustion of fuel, the better;
- quality and thickness of the heat-insulating layer of the water jacket.
If, due to the nature of operation, you need a simple non-volatile unit, then you need to understand that its efficiency cannot be as high as that of a condensing boiler. You will have to rely entirely on the efficiency of the heating system and good insulation building. And in order to additionally remove heat from flue gases, you can purchase a water economizer. It is installed on the chimney and heats the water flowing through the return pipeline.
Conclusion
Modern gas boilers are quite effective devices, in terms of efficiency, they lose only to electric heat generators. But the degree of efficiency of the units is very dependent on the presence of high-tech elements in them, and hence on the cost of the product as a whole. The same condensing boilers are as economical as they are expensive. At the same time, a simple budget unit can fully satisfy you, besides, it is able to work both on natural and on liquefied gas. published
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It is quite logical that every owner of a private house wants to save fuel that 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.
Boiler efficiency principle
Ideally, the heating boiler must first efficiently burn liquefied or natural gas, and then redirect the resulting heat to heat the heat carrier. But in reality, everything does not always go so smoothly, and here are the reasons:
Thus, one part of the energy contained in the fuel is lost during the combustion stage, and the second part is lost during heat transfer. The lower these losses, the more productive the energy is spent and the gas boiler is more economical. The operating efficiency of the heater 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 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%. More inflated power figures, which are indicated by manufacturers of thermal appliances, do not correspond to reality.
Choice of gas equipment
During the selection, the main task is much broader than simply determining which gas boiler is the most economical and reliable. It is necessary that the equipment correspond to the conditions of a private house and fit the heating system. The solution to this problem requires an understanding of what types of heat generators are today and what is their difference from each other. On the this moment There are three types of gas-using equipment on the market:
- pressurized condensing boilers;
- pressurized (turbocharged) with a closed firebox;
- atmospheric with an open firebox.
The above types are made in wall and floor versions. Only in models of atmospheric boilers can you pick up wall-mounted (parapet) products with a side chimney that goes horizontally to the street through the wall. There are double-circuit varieties of boilers used as a boiler to provide hot water.
Execution in wall or floor version does not affect the power and practicality of the boiler. The main thing is only the principle of operation and design heat generator.
Atmospheric aggregates
This gas equipment is not one of the most economical devices, since the efficiency does not often exceed 83%, and the temperature of the burnt gas at the outlet to the pipe is about 160 ° C. The reason is the usual version combustion of fuel with free supply of oxygen from the boiler room. During an excessive amount of air in the air-fuel mixture, not the most favorable conditions for fuel combustion, which adversely affects the efficiency of the heater. The increased temperature of the combustion products indicates inefficient heat transfer and loss of thermal energy.
There is one more important point. Many burners that are installed in cheap atmospheric boilers, can only work in one mode. In other words, to maintain the temperature of the heat carrier, the burner is regularly switched on and off. This is the simplest principle of operation, 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 non-volatile. There are a large number of models from various manufacturers that are equipped with automation and control devices that consume electricity. However, their presence does not increase the efficiency of boiler equipment.
For heating a house with an open firebox running natural way, 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 heat generators
The closed furnace and forced air circulation, which is implemented in these devices, improve the conditions for burning liquefied and natural gas. In turbocharged boilers, unlike atmospheric ones, the following types burners:
- modulation;
- two- and multi-stage.
The point is that when the predetermined temperature of the heat carrier is reached, these burners switch to the lowest level of fuel combustion activity (first type) or gradually reduce the intensity of the combustion process to a minimum (second type). I.e, automated system the boiler control itself controls the burner output, taking into account the heat load or a signal from the outside 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 led out into the street through the wall. This allows not to equip the chimney, and also not to connect the heater to the ventilation shaft, which is strictly prohibited by SNiP.
Condensing devices
By and large, these are the same pressurized heat generators with a closed firebox, but with increased efficiency- up to 97%. This is achieved due to the closed design of the heat exchanger, which surrounds the cylindrical burner around the entire perimeter. Yes, you can return thermal energy vaporization lost during combustion. The resulting water begins to evaporate when elevated temperature during combustion, then the steam after contact with the heat exchanger condenses and transfers back the thermal energy.
Condensing gas equipment is the most economical equipment for heating a private house. Provided that electricity is supplied in the area without interruption or alternative source food - diesel or gasoline generator . Like turbocharged heating boilers, condensing equipment cannot work 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 cottages and in private homes. Ease of use, safety and convenience are the main reasons for the popularity of gas heating. Also, boilers have a number of other advantages:
The heat exchanger of floor heating equipment is made of high-quality and durable cast iron, which provides the best thermal insulation, and modern burners make it possible to operate the device simultaneously on both liquefied and natural gas.
Besides, floor standing boilers clearly respond to negative impacts external environment, their body is covered 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 work still needs to be monitored, since even small interruptions disrupt the normal production cycle.
Theoretically, the most practical and economical gas boilers for heating a private house with maximum efficiency are condensing boilers. However, having learned the cost of this equipment, not any homeowner will dare to purchase it. Therefore, you can buy a conventional gravity system that does not require electricity, automation and a pump.
It is also not very cost-effective to purchase condensing equipment for a small building of less than 150 square meters. m for any type of heating. On this area, the savings will not be tangible, in contrast to the purchase of an inexpensive atmospheric boiler.
When choosing gas equipment, it is not necessary to focus only on efficiency, it is also necessary to be guided by considerations of necessity and expediency. If there is no chimney pipe in the house, it is best to choose a pressurized heat generator when there are power outages - a non-volatile atmospheric boiler. If the cottage is more than two floors, it is advisable to install a condensing unit. It is possible to make an economical boiler in other ways, for example, by the usual insulation of a house.
Modern gas boilers are efficient equipment that, in terms of efficiency, lose only 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.
Variety of boiler brands
What criteria should be used to evaluate a gas boiler for a home when purchasing equipment for local system heat supply, you will learn from this article.
Efficiency of gas boilers
First of all, it is necessary to understand how the thermal energy of the burning fuel is distributed. The energy carrier for a gas boiler is natural or liquefied gas, while the calorific value of any of these fuels must be within regulatory requirements- only in this case the heating unit will be able to generate heat in accordance with its passport indicators.
The calorific value of gas is a value indicating how much heat is released during the combustion of a unit volume of fuel. The heating unit directs the bulk of this energy to heat the coolant in the building system, i.e., to heat the house. The greater the percentage of energy will be used to solve this problem, the better.
The efficiency of a heat generator (expressed as a percentage) is an indicator of exactly what part of the heat of combustion of the energy carrier is used to heat the house. The higher the efficiency, the more efficiently the fuel is used, the less it is required to maintain the heating system in normal mode.
Efficiency and economy depend on each other In turn, the more fully the fuel is used and the lower its consumption, the less money is spent on the purchase of an energy carrier. Thus, the efficiency of the boiler is directly related to its efficiency.
In the combustion process gas fuel under normal conditions and with a sufficient supply of oxygen, CO 2 (carbon dioxide, also known as carbon dioxide) and H 2 O (water) are released.
Thermal energy obtained as a result of gas combustion is consumed:
- for heating the coolant;
- on the evaporation of water vapor obtained during combustion;
- goes down the chimney along with flue gases.
The most economical gas boilers differ from the rest in that the absolute maximum of thermal energy is directed to heating the house, while losses in the last two items on the list are minimized.
Combustion chambers and burners
The efficiency of a heat generator running on natural or liquefied gas is usually 90-95%, for premium units this figure can reach 98%.
To a certain extent, the efficiency of the device depends on the characteristics gas burner with which the boiler is equipped.
When choosing a heat source, you should pay attention to the type of combustion chamber of the unit - it can be open and closed:
- air enters the open combustion chamber from the room;
- air enters the closed chamber from the street through a coaxial chimney, and is blown by a fan.
Obviously, in the second case, the combustion process takes place at a higher oxygen supply, due to which the fuel burns out almost completely, giving off thermal energy to the maximum. This not only reduces the amount of flue gases, but also increases the efficiency of the boiler.
The burners themselves are of two types - with step and smooth adjustment, thanks to which you can change the power of the unit. The most inexpensive units are equipped with a single-stage or two-stage burner.
If the gas boiler is equipped modulating burner, controlled by electronics, it is able to save energy as much as possible. This is due to the fact that the degree of heating of the coolant is smoothly regulated depending on the real needs of the house for heat. This is one of essential conditions reducing fuel costs during the heating season.
Attention! It makes sense to install an efficient and reliable gas unit with a modular burner and forced air supply to the furnace as part of a heating system with individual microclimate control in each room. This requires serious investments at the stage of purchase and installation of equipment, but in the future the system pays for itself due to serious energy savings.
A little more about the efficiency of boiler plants
This indicator depends not only on the characteristics of the furnace and burner device, but also on how thermal energy is transferred.
At the first stage, the heat received in the combustion chamber heats the water jacket of the unit. Then the flue gases and the remaining thermal energy pass through a heat exchanger made of steel or cast iron, due to which another part of the thermal energy is spent on heating water. The remaining heat, together with flue gases, escapes into the atmosphere through the chimney.
If you measure the flue gas temperature at the outlet of the pipe, you can evaluate the efficiency of boiler equipment. In a heater with low efficiency, the temperature of the gases at the outlet pipe reaches (or even exceeds) 200 degrees - this means that a significant part of the thermal energy is irretrievably lost, that is, a decent percentage of the fuel is wasted. Gas heating boilers can be considered quite efficient if the temperature of the flue gases at the outlet of the pipe does not exceed 150 degrees. For an economical boiler, this figure will be about 100 degrees.
Outgoing flue gas parameters The lowest temperature for combustion products is for condensing gas boilers. This is achieved thanks to design features unit, where a system is provided for the selection of heat obtained during the vaporization of water. As mentioned above, water is released during the combustion of gas fuel, and then evaporates - and part of the received thermal energy is spent on this evaporation. Condensation colas differ from classical gas units in that they take this energy back by condensing water vapor.
The condensing model is equipped with a cylindrical type burner, which is mounted inside a stainless steel heat exchanger, made in the form of a coil with coils located very close to each other. The coolant circulates through the coil. The water vapor formed during the combustion chemical reaction passes through the coil, since it has no other way, and condenses on its surface. In the process of condensation, the steam gives off heat to the coil.
When determining which gas boiler is the most economical, one should pay attention to condensing boilers, since the temperature of the combustion products at the outlet of the pipe is the lowest - only 45-70 degrees, while the efficiency is 98%.
What to choose: condensing or conventional boiler?
As already mentioned, the efficiency and reliability of the condensing boiler is beyond doubt. But it should be noted that sellers of such equipment often mislead buyers by declaring that the efficiency of a condensing heat generator is more than 100%. They to baseline in 98%, “percentage of efficiency” is added, obtained due to the condensation of water vapor - that is, the thermal energy that the unit takes back, initially spending on converting water into steam.
A photo of a condensing boiler Any literate person who studied physics at school knows that the efficiency of equipment cannot exceed 100%. The condensing unit is able to minimize heat loss, but cannot increase the amount of heat energy obtained by burning gas. Thus, the real efficiency of the condensing heat generator does not exceed 98%.
However, when choosing a gas-fired heating unit, it is important to consider the following:
- condensing boilers are more economical than conventional ones, but are significantly more expensive due to their more complex design;
- maintenance of the traditional gas unit(flushing the heat exchanger, etc.) can be done by hand, technically there is nothing complicated in this, and certified specialists are required to clean the condensing boiler.
If you are looking for an economical gas boiler among conventional units, then it is important to understand that savings when buying equipment in the future can turn into increased costs for repairs and maintenance.
Don't Forget to Estimate Installation Costs.
For example, a floor-standing gas boiler with open cam combustion requires installation in a designated area with a fire-resistant finish. In addition, a foundation and a vertical chimney are mounted for it.
A model with a closed combustion chamber can be installed in any convenient place and lead the chimney through the wall.
Compact gas boilers are hung on the wall and take up a minimum of space - this is the most convenient option.
Please note: it makes sense to opt for a non-volatile boiler only if it is not possible to provide power to the equipment. Such models have a relatively low cost, but do not make it possible to save fuel.
How to make the right choice?
Compare the following indicators:
- Efficiency of the unit (indicated by the manufacturer in the product passport);
- temperature level of combustion products at the outlet;
- design features of the heat exchanger (the more turns, the more heat energy the flue gases will have time to give off);
- the quality of the thermal insulation of the water jacket of the boiler (it is important that there are no unnecessary heat losses);
- type of combustion chamber;
- burner type (smooth adjustment is the ability to switch the boiler to the most economical mode of operation relative to specific conditions).
The installed heating boiler for a private house must be properly adjusted, this must be done by specialists. Practice shows that it is not worth further saving on the invitation of experienced professionals to adjust the heating unit - even the slightest deviation from optimal modes functioning of the nodes lead to the fact that the operation of the boiler becomes less efficient and more fuel is spent.
The choice you made will not disappoint you if you take into account all the recommendations. But it should be understood that an economical boiler will meet expectations only if the house is well insulated, selected best option heating system, fuel with the correct characteristics is used.
Whatever high performance at the boiler unit, it requires regular preventive cleaning - accumulated pollution reduces the power of the boiler and provokes excessive fuel consumption.
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Gas prices are constantly rising, so for homeowners the problem of how to save on gas heating. Hence, it becomes necessary to choose from the range of gas heating units the most economical gas boilers for the home, which allow inexpensive heating of houses.
Features of choosing an economical gas boiler
Before choosing an economical gas heating boiler, each buyer must answer 3 questions that are basic:- what is the required power of the device for high-quality heat supply to housing;
- how economical should the equipment be;
- how to decide on the manufacturers of gas units.
What is the required boiler power
There is a certain procedure for calculating the required power of heating units. To do this, you need to add up the power required for heating the house and hot water. Simultaneous operation of both circuits must be provided with a sufficient amount of energy.In practice, it is customary to use a simpler method: the required power is calculated taking into account the area of \u200b\u200bthe room: for every 10 "squares" 1 kW of thermal energy is required. So you can choose the most economical gas boiler for your home.
By design decision gas appliances are divided into 3 groups:
- hinged;
- floor;
- condensation.
Mounted boilers mounted on the wall, installed on the floor, but condensation can be floor or wall. The main difference of the third group is high efficiency, reaching 100%. Economical gas heating boilers are precisely condensing. Such high efficiency possible due to the use of two sources of thermal energy. The first of them is the combustion of gas, and the second is the energy that is released during the condensation of steam coming from the boiler together with smoke (more: "").
The advantage of floor-standing gas-fired heating units is characterized by increased reliability and ease of maintenance. This difference is explained by the simplicity of the design solution, which is based on a large-sized cast-iron blank.
Mounted boilers, which are shown in the photo, are easy to install, and all important components, such as expansion tank, circulation pump, automation are combined in one building. A chimney is not required for such appliances. The cost of hinged heat units is lower than other models of heaters operating on natural gas.
Manufacturers of gas heating boilers
The choice of a manufacturing company is based, first of all, on the ratio between the quality of the equipment produced and its price.The final decision is based on one of three defining points:
- lowest cost;
- the best quality;
- the so-called principle of "golden mean" - the ratio between price and quality.
If necessary, choose an economical gas boiler, best solution will be the first option. But in this case, the savings will be temporary. The fact is that the money saved on the purchase will be required in the future for repairs. In addition, cheap heat units are not distinguished by economical fuel consumption.
Therefore, by spending a large amount, the buyer becomes the owner of better equipment.
When purchasing economical gas boilers for the home, it is necessary to simultaneously resolve all issues related to the installation of units. Installation of devices and their connection to the gas main must be done by highly qualified workers. Otherwise, the risk of accidents increases.
Other types of boilers to save on heating
For space heating, you can use not only economical gas boilers, but also other types of heat units. They can be considered as an alternative heating systems using natural gas. Typically, such devices are used to heat individual rooms, such as a garage or greenhouse.Currently, you can find the following groups of heaters and heat supply systems associated with them:
- Electrical. Economical electric boilers exist and are not fiction, only they are so compared to others heating appliances that require power. This is understandable, because of all the energy sources used for heating, electricity is considered the most expensive pleasure. Even the most economical electric boilers for heating they lose to devices operating on a different type of fuel.
- Solid fuel. They function at the expense of coal, firewood, etc. Economical solid fuel heating units require constant monitoring and care. This is their main drawback. But, in general, such heaters are considered the most economical.
- Liquid fuel. They cannot be used in apartments, as they are very flammable. For their operation, the room should be strengthened with fire protection.
From here, we can conclude: even the most economical gas boilers for the home in many ways lose to heaters that operate on other types of energy carriers.
Saving gas during heating is possible only if modern equipment is installed, and it costs a lot.
The video details about economical gas boilers for the home:
Gas is much cheaper than other energy sources. But with inefficient consumption, a lot of money will be spent on heating for nothing.
Manufacturers are doing everything possible to reduce natural energy losses during the operation of the boiler. What is economical heating for a private house, how can savings be made?
The main characteristic of fuel is its calorific value. It is expressed as the amount of heat released per unit of fuel burned.
Today, the optimal calorific value is defined as 8 thousand kilocalories (or 33.5 thousand joules) per cubic meter minimum. The most economical gas ones are those in which the energy of combustion is almost completely spent on heating, and the losses are negligible.
The combustion process involves two chemical element: the gas itself and oxygen from the air. When heated, these substances begin to interact. The reaction products are carbon dioxide and water.
The energy that is released in this case goes away:
- for heating the coolant;
- into the chimney together with the products of combustion;
- for the evaporation of the escaping water.
The design of economical gas boilers allows minimizing the second and third components. Standard indicator the efficiency of the unit varies between 90-98 percent. The lowest efficiency is for simple convection models with an open firebox, the highest is for condensing boilers ().
In figures, this is expressed as follows: at the boiler, which can be considered as a source of heating, the temperature of the outgoing smoke does not exceed 150 degrees. In the condensation model, this figure is within 70 degrees, the maximum efficiency is 98%.
If the figure is more than 200 ° C, this boiler is not worth buying. Similarly with water vapor: in a simple model with smoke, about 6 percent of steam is lost, in a condensing one - 0.5%.
Sometimes advertising brochures indicate the figure of 110 percent, but this is nothing more than a marketing ploy designed for an inattentive buyer. Efficiency above 100 can not be in principle. 100 is perfect option: it is assumed that the boiler operates without losses at all, which is technically unattainable.
Device Features
The working units of the boiler are a burner (), a heat exchanger, a chimney. The burner heats the water in the heat exchanger, the gases are discharged to the street. Air intake can be natural (directly from the room, in the case of an open firebox) or forced (through a coaxial tube from the street, blown by a built-in fan).
The process is to some extent regulated by automation (). Efficiency depends partly on the adjustment, partly on the design of the nodes themselves.
For a simple burner with piezo ignition, the power is regulated in steps, one or two options. Modulating electronic allows the same to perform smoothly. In a simple igniter, it burns constantly, only the gas supply is regulated. The electronic igniter fires as needed.
The condensing boiler has a cylindrical stainless steel burner placed inside the heat exchanger. The heat exchanger is made as a coil with closely spaced coils.
As it travels through the spiral, the steam condenses on the surface of the water chamber. The process proceeds with the release of heat. The conventional model has a simple-shaped heat exchanger, the process is carried out quickly, the steam does not have time to condense and flies into the chimney.
That is, when choosing a model, you need to pay attention to the following things:
- type of furnace - open, closed;
- Efficiency specified in the description of the model;
- outlet gas temperature depending on the operating mode of the boiler;
- the shape of the heat exchanger: the more complex the geometry, the more steam will condense during combustion;
- the quality of thermal insulation and the thickness of the heat insulator layer of the water jacket. The purpose is to reduce heat loss.
Another criterion is the price of the unit. Condensing models are significantly more expensive. You can buy a simple non-volatile boiler and install a water economizer on the chimney - standalone device, which will heat the coolant in the return.
It is desirable that the model can work on both main and liquefied gas. Tapping into the highway is not possible everywhere, but this is the cheapest and easiest option to manage.
When buying a condensation model, you need to take into account that it is optimal for working with low initial temperatures and a slight delta between supply and return (on the return - within 40 degrees).
Wall or floor
The wall-mounted boiler is more compact, it can be hung in any room.
The floor has more dimensions, power, required separate room under the boiler room. Consider what is more profitable in your case.
floor boiler
They are usually installed in houses with an area of 200 square meters. Most of models - single-circuit with an open firebox and simple automation. Due to the simplicity of the device, it is easy to choose a boiler with a budget cost.
The disadvantages include large dimensions and weight. The boiler room should be well ventilated, the boiler needs to be properly arranged chimney: it provides efficient removal of combustion products and draft inside the chamber.
For installation, it is desirable to involve professionals. Be sure to arrange a platform under the boiler made of non-combustible material and a sufficient distance from walls and other flammable surfaces.
Another feature of the floor model is that it cannot work at low pressure, because. the intensity of the burner flame is reduced. And in severe frost, the pressure in the line usually decreases.
Wall
It is hung on the wall on special brackets. The surface of the wall section near which the boiler is located is equipped with fireproof material (metal, asbestos).
The dimensions of the boiler are small, the weight is also (within 50 kg). The boiler room is not needed, you can hang it in the kitchen, bathroom, living room. The variety is greater: many models with a closed firebox, condensing, double-circuit.
The complete set of the unit may include all necessary elements systems: pump, expansion tank, coaxial chimney, automation. In the presence of coaxial chimney the requirements for ventilation of the room are lower than with a simple system with an open firebox and a standard pipe.
A feature of such boilers is more complex automation. It is more difficult to regulate and debug it with your own hands; for repairs, you need to call a professional master.
Wall-mounted boilers are divided into flow and boiler. If necessary a large number hot water choose boiler units or attach an additional drive to the column.
Double circuit or single circuit
More convenient, of course, double-circuit: it not only works for heating, but also provides the house with hot water. It costs more, and this is not the only negative: the boiler cannot work on and hot water at the same time. When you open a hot faucet, the heating will automatically turn off.
This is not fatal if the house is large and the circuit is long: the system does not have time to cool down while the hot tap is open. Moreover, it is not scary in the summer when the heating is turned off. For small houses that are operated all year round, this feature is critical: as long as hot water, the circuit has time to cool down.
Then it takes a lot of additional energy to warm up. In this case, the most economical gas boilers for a private house are single-circuit: fuel is consumed economically, the system works without interruption. For DHW needs It is better to buy a separate heater.
Conclusion
It is also worth mentioning that even when using a non-volatile boiler, you will need electricity: a circulation pump works on it.
Therefore, it is not advisable to save on automation just for the sake of independence from the network. Worth having on the farm offline source energy (for example, a generator).
If interruptions in the power supply are short-term, you can limit yourself to purchasing an uninterruptible power supply.
Video how to choose a gas heating boiler.