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. The standard indicator of 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 - an autonomous device that will heat the coolant in the return.
It is desirable that the model can work both on the main and on 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 consider 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, a separate room is required for 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 must be well ventilated, the boiler requires a well-designed 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 floor model- 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 a large amount of hot water is needed, boiler units are selected or an additional drive is attached to the column.
Double circuit or single circuit
More convenient, of course, double-circuit: it not only works for heating, but also provides a house 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 - single-circuit: fuel is consumed economically, the system works without interruption. For hot water 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. It is worth having an autonomous source of energy on the farm (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.
One of the most milestones building a private house is the choice of heating. To create a heating system, first of all, you need to decide on a boiler. On the this moment The market offers a huge range of domestic and foreign manufacturers. Therefore, in order to buy a boiler that will best fit into your home, you need to correctly navigate the huge variety of products.
Since the price of heating increases every year, people began to seriously think about the possibility of using alternative ways heating.
Economical wood-fired boilers for heating a private house today have taken a leading position in the market heating appliances, because such boilers produce a large number of heat with minimal use of wood.
Wood is not the only fuel.
Boilers using solid fuels work not only on wood, but also on peat briquettes, coke, coal or brown coal.
Economic boiler long burning has many advantages:
- High level of efficiency;
- Complete independence of the boiler from external communications;
- Inexpensive fuel (when compared with gas);
- Possibility to choose fuel.
How solid-state long-burning boilers are arranged
The operation of the boiler begins with smoldering processes. In boilers of this type, the oxygen supply can be regulated. With a small amount of air, smoldering processes can last a very long time.
The need to refuel such a boiler does not arise so often. Another plus controlled process smoldering is fuel economy, which burns as slowly as possible, while releasing a sufficient amount of heat.
The operating time of the boiler from one filling depends on the selected model of equipment. On average, the boiler can work up to two days, although there are such models whose operating time reaches 3 days.
Technical characteristics of solid fuel boilers
Of course, each boiler has its own technical features, but there are also average values:
- Power about 100 kW;
- Main types of fuel: wood, coal, peat;
- Efficiency about 89%;
- Outlet water temperature from 50 degrees;
- Pressure 1 atmosphere;
- The duration of continuous operation without reloading is 10-12 hours.
An economical solid fuel boiler for heating a private house has an increased protection system. This boiler is perfect for absolutely any room.
Most often, boilers of this type are used in places where it is impossible to operate gas or electric boilers. Solid fuel boilers are not afraid external factors or, for example, lack of electricity.
Service life of cast iron solid fuel boiler is about 20 years
The main competitor of wood burning boilers are electric heating boilers. This type of boiler is also quite often installed in private homes. The undoubted advantage of electric boilers is their high safety.
How to choose an electric boiler and save
The first thing you should pay attention to when choosing an electric boiler is power. The most economical boilers for heating a private house have no more than 3 kW of power per 30 sq.m of space.
Highly important point is the choice of boiler power for rational energy consumption.
Economical electric boilers can have a power of 6 to 30 kW and are perfect for any room.
Advantages of electric boilers
Boilers for heating a private house of an electric type can often be seen in country-type buildings. This type boilers have the following advantages:
- Simple external design;
- Easy to install;
- Occupied space;
- No chimney;
- Fire safety system.
Disadvantages of electric boilers
Despite their advantages, electric boilers have a number of disadvantages.
- High power consumption
If you want to minimize the disadvantages presented above, you seriously need to think about buying an expensive boiler that comes with savings programs.
These programs are able to support user-installed temperature regime. Some boilers have temperature sensors and independently regulate the heat of the room.
Which boiler is best for a private house
As you could understand from this article, economical boilers for heating a house - perfect solution if you want to go from central to autonomous heating or simply do not have the opportunity to heat your room in a different way.
Modern boilers do not need constant monitoring, are easy to operate and have the highest possible efficiency. Unfortunately does not exist one-stop solution. For someone the most good boilers heating for a private house is gas, for some it is electric boilers, someone prefers classic solid fuel boilers.
In any case, each of the boilers presented above will allow you to easily survive even the harshest winters.
Most buyers are trying to purchase an economical floor-standing gas boiler for their home, since gas is not cheap today. But, in addition to fuel consumption, there are many criteria by which the unit is considered economical. This is the service life, and the operation of the weather-dependent system, and the efficiency of the unit.
The efficiency of a gas unit directly depends on its service life. Boilers with cast-iron heat exchangers are able to work the longest - their service life is 30-40 years. However, they can "live" for so long only with careful handling. Cast iron is brittle and must be handled with extreme care. It is also necessary to avoid getting cool water on the surface of the hot heat exchanger, as the temperature difference will lead to cracks.
Floor-standing units with steel contours are not as capricious as cast-iron ones, but they are much more susceptible to corrosion. Because of this steel elements fail faster.
The service life also depends on the availability of spare parts and the quality of the heating equipment. Therefore, when buying a unit of a certain brand, you should ask if it is easy to find accessories for it. As for the manufacturer, German and Slovak units work the longest. Domestic analogues fail faster, but they are better adapted to the difficult Russian operating conditions and will cost less.
Note! Many manufacturers recommend installing for their gas boiler Voltage regulator. This is a condition for continued warranty service.
Some owners of outdoor gas boilers are trying to save on after-sales service and do not call a specialist for scheduled repairs. However, during operation, the focus of the burner may shift, soot may appear and other minor malfunctions may occur. If they are not eliminated in time, then fuel consumption will increase, and the performance of the unit will decrease. Therefore, it is better not to save on service.
How does automation make a gas boiler more economical?
The efficiency of a gas unit is also affected by the ability to reduce and increase productivity during operation. Modern weather-dependent systems are able to reduce the intensity of combustion depending on the temperature outside or in the room. This significantly reduces gas consumption and, accordingly, the cost of it.
Some modern systems automation can be set to work for a day or a week. You can set the operation of the gas unit so that at night the temperature in the room is lower.
There are floor gas boilers with these types of burners:
- single-stage - has one power level;
- two-stage - two power levels;
- modulating - several power levels.
The last type of burner is considered the most economical, as it has the ability to smoothly switch to different power levels.
Efficiency of outdoor gas units
The main indicator when choosing an economical gas boiler for organizing home heating is the coefficient of performance - efficiency. Its value for outdoor gas units lies in the range of 84-99%. Low-cost devices equipped with a one- or two-stage burner have a low rate. Boilers work more efficiently, in which the power can change smoothly, depending on weather conditions.
The heat that is obtained as a result of gas combustion heats the heat exchanger with the heat carrier. After that, the remaining heat passes into the chimney and irrevocably goes into the atmosphere. The amount of heat lost is shown by the flue gas temperature. If the smoke is heated to 200°C or more at the outlet of the nozzle, then this unit is not considered economical. The best option- flue gas temperature within 100-150 °C.
Condensing gas boilers
The condensing unit is considered the most economical floor gas boiler for the home. This is possible thanks to a special technology for extracting heat from the resulting moisture. To do this, a floor-standing gas boiler is equipped with a cylindrical burner, which is located inside a stainless steel heat exchanger. It is made in the form of a coil with tightly packed coils. Water vapor condenses on the heat exchanger, the heat from which also heats the coolant. Due to this, thermal energy is maximally spent on heating the heat exchanger. The efficiency of such units is 97-99%.
Note! If, due to problems with electricity, you decide to purchase a non-volatile gas boiler, then keep in mind that it will not be economical. For such boilers, the efficiency rarely exceeds 91%.
The cost of floor gas boilers
Another important selection criterion is the price of the device. Condensing models are much more expensive than convection models. It is better to purchase a boiler that can work on both natural and liquefied fuels.
Mainly to devices available price category include models with low efficiency. More efficient units, especially foreign-made ones, are more expensive.
If you cannot afford condensing-type heating devices, you can purchase a cheap domestic boiler with low fuel consumption.
Along with the increase in demand for natural gas, its prices are also increasing. And this is not surprising, it is thanks to him that in winter it becomes warm in our homes. But as you know, in order to warm the room well, you need a lot of gas, which can hit your wallet hard. Therefore, many began to switch to economical models gas boilers, their advantages are low gas consumption and low cost.
Wall-mounted gas heating boiler
But unfortunately, not everything is so simple, having bought cheaper, you can overpay at exorbitant prices. Why? The fact is that the reliability of these models is low, and gas and equipment associated with it does not tolerate frivolity. Therefore, the most economical gas boiler for the home is not always the right choice. Although there are exceptions that clearly show that there are still high-quality and not expensive boilers.
Economical gas boilers
Economical gas boilers are called equipment, the efficiency of which is as close as possible to one hundred percent. Here it is worth noting that these devices have a class: premium, middle and other classes. Naturally, their efficiency varies and for medium ones it is in the range of 70-90%, while for premium these figures are at the level of +/- 95%.
The difference in the cost of classes of gas boilers is also quite significant, and can be over 50%.
An important aspect when choosing a heating system, the country of origin is the country of origin, many experts note that it is cheap, but unreliable domestic manufacturers. Maintenance such units can "eat" all, it would seem, a significant difference when buying. Therefore, choosing such important element think about the future, because one of the most important criteria in this matter is reliability.
Fuel for boilers
Stylish gas boiler model
It is no secret that at the moment gas is one of the cheapest types of fuel, despite the systematic increase in prices for it. An important aspect of choosing a fuel is availability, even now not all homes have gas, which means that something else must be used instead, for example, diesel fuel.
But the question arises, what to do if the gas will soon be carried out, but now it's cold? The answer to this is simple, there are special ones that can successfully operate on both one and the other type of fuel. One of these instances is a double-circuit. It is unpretentious and quite economical. There are also models in which it is enough to change gas burner to diesel, and behold, your boiler runs on gas. Of course, if the gas has already been brought to the house, then such problems and questions will not arise, and nothing will prevent you from immediately installing the most reliable and economical model.
Life time
The service life of heating equipment operating on gas fuel, this is one of the most important parameters for these units and for different boilers, it is different. This parameter varies due to parameters such as manufacturer class and others. For example, an economical premium gas boiler will “live” longer than its counterpart from the middle class, which will last a maximum of 15 years. It is just as important how your boiler works, constantly or intermittently. Here ACS can play an important role ( Automatic Systems Controls), which regulate the operation of the boiler, we will talk about them in more detail a little later.
It is also worth noting a point that indirectly affects the topic of saving. As you know, burners in gas boilers are divided into two types:
- Fan or inflatable, which operate on the principle of mixing gas with air before this mixture enters the combustion chamber.
- Atmospheric, in which this process occurs in a natural way.
Inflatable gas boiler system with burner
It is in fan burners that the gas-air mixture burns completely, which guarantees an increased efficiency compared to atmospheric ones. It is also worth noting the comparative cheapness in the case of repair of equipment with a fan-type burner. Maintaining them will save you 25-35%.
Automatic control systems
This is one of the most useful innovations, and it has affected heating systems relatively recently, and is already gaining well-deserved popularity. These systems themselves regulate the temperature in the room, according to your presets. Moreover, some allow you to do this while in the room, by placing a special sensor in the room, on which you can set the temperature. But that's not all, there can be several such sensors, and different rooms will heat up differently.
Inexpensive model of a gas boiler with ACS
More advanced systems independently check the temperature outside to correct the temperature regime.
Thus, with a sharp warming, the system itself will lower the temperature in the house. It is also worth noting the latest innovations that can be controlled from a cell phone, and in case any unforeseen event occurs, such as a power outage, you will immediately receive an SMS alert. The presence of automated control systems can reduce fuel consumption by 10-20%.
Knowing the main characteristics and points that you should pay special attention to, you can easily choose and purchase a high-quality, efficient, but most economical gas boiler for your home.
What is economical heating? The one that was cheap to purchase equipment and install? Or where the cost of each received kilocalorie of heat is low? As a rule, they mean the second. However, in addition to the cost of fuel, there is also the cost of maintaining equipment and it is often preferred to hush it up. Is it possible to call an economical heating system in which the specific cost of a unit of thermal energy is unprecedentedly low, but investments in equipment are so high that their payback period exceeds the service life?
Which house has the most economical heating
Answer: in the house that is best insulated. No matter how much effort and money we invest in engineering communications, if the building is poorly insulated, we will still incur unreasonably high heating costs. First of all, you should pay attention to the thermal insulation of enclosing structures: external walls, roof, floor of the lower floor, windows and doors.
The ratio of heat loss through various building envelopes of an average individual residential building
In addition to the minimum requirements for thermal insulation, the current Russian standards also contain recommended parameters. The minimum allowable characteristics of enclosing structures are determined by calculation and depend on climatic conditions terrain. Example: thickness is enough for the climate of the Moscow region outer wall from gas silicate blocks with a density of 500 kg / m2 in 40 cm, but additional external thermal insulation mineral wool at least 8 cm thick.
When insulating a house Special attention give "cold bridges": concrete lintels, the ends of floor slabs, reinforced belts, window slopes etc.
How much does comfort and personal time cost
Oddly enough, the efficiency of heating is a somewhat relative concept. For example, the owner of a private house lives in a non-gasified, but wooded area and has the opportunity to harvest firewood very cheaply in the volumes he needs. Fuel costs, even with a primitive heating system with an ancient, monstrously voracious CFM and registers instead of batteries, will be extremely low. However, the owner will have to work hard to prepare firewood, do not forget to periodically load it into the furnace, clean the boiler, take out the ashes, put up with uneven heating, the impossibility of fine adjustment. The homeowner can invest in the modernization of heating, purchase an automatic pellet boiler, and make modern wiring. Wood fuel consumption in kilograms (tons) will decrease by three times, but the cost of each kilocalorie will seriously increase. In this case, what is the most economical heating - wood or pellet? At a specific price, kcal is undoubtedly the first. In terms of quantitative fuel consumption - the second. How to evaluate free time, which the owner of the house will have after switching to pellets? In addition, a more advanced system will create high thermal comfort in the premises, and this, after all, is also worth something.
The cheaper it is to heat a house
If we discard the possibility of harvesting firewood for free and focus on the average prices of Central Russia, natural gas has been the cheapest fuel for many years. It also allows you to fully automate heating, modern gas boilers require only preventive maintenance once a year. Only electric heating, but it costs many times more. Even for Western Europe, where the price of gas relative to other types of fuel is much higher than in the Russian Federation, the most economical home heating is gas.
The table reflects the comparative cost of thermal energy for prices in the Moscow region. And if for gas, diesel fuel and electricity in other regions the cost ratio will be similar, then the prices for pellets, firewood and coal can vary greatly depending on local conditions.
There is no alternative to heating with natural gas for gasified areas. If there is no gas pipeline nearby, you need to calculate what is ultimately more profitable. Laying the highway is not a cheap pleasure. The initial investment in equipment also matters.
The ratio of costs for the purchase and installation of heating equipment.
As you can see, the initial costs of electric heating, especially direct heating, are the lowest. The level of comfort and safety is maximum, it is easier to solve issues with electricity than with gas, there is no need for a chimney. The main thing is that there is enough electric power. It is precisely because of the low start-up costs and ease of installation that buildings built on the principle of a “passive house” (there are such in our area) are increasingly heated with electricity. Based on the combination of initial and operating costs, it turns out that in this case the most economical - electric heating. We repeat that this applies only to modern, well-insulated buildings with low specific heat loss in the absence of a gas pipeline.
Heat from alternative sources
The statement that the most economical heating is from alternative sources, is not true. Fluid pumps in geothermal and solar systems consume electricity. And it costs a lot of money. Today, heating with gas at our prices is still more profitable than installing a heat pump. And there is no need to talk about any serious use of solar collectors in the domestic climate. Today, a more justified solution is the creation of a combined heating system: a heat pump designed for 70% of the required power, and an additional solid fuel (pellet, electric) boiler or fireplace, which gets the missing 30% during severe frosts. Solar collectors, as a rule, are used only for heating hot tap water. Recall that the cost of "alternative" equipment is still so high that in the conditions of the Russian Federation it often does not even pay off during its service life, if we compare its performance with wood heating.
Using the temperature difference between the two media, the heat pump draws energy from environment. However, for the constant circulation of the refrigerant and the selection of energy from it, rather powerful pumps operate that consume electricity.
The most economical heating scheme
In water heating systems, in addition to the type of heat generator (boiler), efficiency also determines the type heating appliances, heating scheme, the nature of the wiring, the presence of automation:
- Among heating devices, heated floors are the most economical.
Underfloor heating is more economical than radiators due to a more even distribution of temperature in the room
- The most economical and comfortable water heating scheme is collector (radiation). Not cheap, but extremely comfortable. It is followed by a two-pipe, it can be considered the golden mean. At a moderate cost, it is quite effective. A simple one-pipe circuit does not allow adequate regulation of the heat transfer of devices.
Collector wiring allows you to best balance the hydraulic resistance of the circuits, adjust heat flows
- Automatic control heat flows at all levels (boiler, distributors, appliances) also significantly reduces fuel consumption.
Due to the low fuel prices so far, we are used to squandering thermal energy. And in rich, but very economical Germany, it is hardly possible today to find a radiator without a thermostat.
- The most economical heating of a private house is the one that is correctly calculated and competently, professionally designed, installed and configured.
How harder equipment, the more you can save by setting it correctly. This is not an easy task and requires specialized knowledge.
Economic heating with electricity - myth or reality
The Internet is full of commercials and articles about "innovative most economical electric heating boiler" and "super electric batteries for economical heating and similar miracles. All this is nothing more than cunning marketing barkers that have nothing to do with reality. In fact, the efficiency of all electric heaters, regardless of their type, approaches 100%. Treasured savings simply nowhere to take. There are only two real ways to reduce the cost of heating with electricity:
- Install a two-tariff meter and heat mainly at night. From 11 pm to 7 am on weekdays and all weekends, depending on the region, electricity costs 1.4-2.1 times cheaper. Having invested in a heat accumulator of sufficient volume, you can stock up on cheap night energy for the day.
- Use underfloor heating to the maximum: water, with heating from a boiler, and direct heating - cable, film. The savings are relatively small, 4-6%, but in the end, a round sum will come up.
The most economical heating boiler
- Gas. The least fuel is consumed by modern condensing boilers with modulating burners. Savings compared to standard counterparts without condensation - 11%, this is a lot. However, it should be borne in mind that the advantages of such boilers can be fully realized only in a low-temperature heating system, this will correspond optimal mode boiler operation. Initially, underfloor heating is low-temperature, but the number of sections in the radiators will have to be almost doubled. We can safely say that the most economical heating of a private house is gas, low-temperature, based on condensing boiler, built according to the ray scheme.
Condensing boilers utilize the potential energy of flue gases, in particular steam
- solid fuel. Pellet and wood pyrolysis boilers consume the least wood fuel.
- Electricity. As already mentioned, "most economical electric boiler for heating "- this is a myth, the efficiency is the same for everyone.
- Liquid fuel. The most economical liquid fuel boiler - on used engine oil. The only question is where to find a permanent source of this almost free type of fuel.
Universal oil burners capable of operating on diesel fuel, biofuel, heating oil (petroleum heating oil) and mining
In conclusion, we emphasize that the creation of efficient and comfortable heating requires a professional approach. You can try to do everything with your own hands, but for this you will have to at least learn the basics of heat engineering and hydraulics. If it is possible to devote some of your personal time to these sciences, the selection of equipment and installation work no, we advise you to entrust the design and installation engineering communications experienced professionals.
Video: economical home heating
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