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Today it is difficult to surprise with gas heating equipment. Boilers are everywhere installed in houses and apartments. Therefore, one of the main selection criteria is the efficiency of the device. The gas condensing boiler is one of the new developments of manufacturers. For the Russian market, this is a new solution. Before deciding to buy, you need to weigh all the pros and cons of the equipment.
The device and principle of operation of the condensing boiler
For the first time such equipment was produced in Holland. Today, residents of the United States and Canada are subject to preferential taxes when installing gas condensate boilers. And in Europe, units are used in 70% of cases.
What is a condensing device? The principle of operation is similar to a conventional convection apparatus. Gas is used as fuel. The equipment is connected to the line or cylinder of liquefied gas. During the combustion of fuel, carbon dioxide and water are produced. Under normal circumstances, condensation on the surface of parts is undesirable. In this case, it accumulates in a special heat exchanger.
When moisture evaporates, kinetic energy is generated, which is used to heat the coolant.
The coefficient of performance (COP) of a conventional product is ± 90%. It turns out that the remaining 10% of the heat simply “flies out into the chimney” along with the combustion products. The difference between a condensation device and a conventional one is that these 10% are directed to a useful channel. Therefore, the efficiency is almost 100%.
How does the technique work? After the main process of fuel combustion, the condenser cools the gases to the “dew point” (50-60 degrees). Thus, the gas turns into water, while releasing additional energy. The condensate unit transfers this energy to the heat carrier.
This is the principle of the new technology. Now let’s look at the structure.
The design does not differ from a conventional heating heater, except for the additional heat exchanger present in it.
Initially, the primary radiator heats up. As a result, combustion products are produced, which enter the condenser, where they are subject to processing. The condensate is collected in a separate tank, after which it goes to the drain through a pipe.
Interesting! Imagine condensation as pure dew drops? Alas, it is not. It accumulates from exhaust gases, therefore it contains undiluted acids, which become aggressive at high temperatures.
That is why all the components and components of the structure are made of stainless steel, silumin. These are acid resistant materials. Radiators are made cast, without vulnerable seams. The same applies to the chimney. Its pipes are made of plastic or steel. All condensate that has not accumulated in the heat exchanger settles on the outlet pipes.
Varieties of boilers
Mounting options include:
- Floor tank. Large and powerful units that require a separate room. For installation, the floor is necessarily strengthened, the foundation is poured.
- Wall. Due to its compactness, it is used both in houses and apartments.
- Universal. Suitable for wall and floor installation.
Boilers for a private house are:
- Single circuit. It is designed only for providing hot water supply (DHW).
- Dual circuit. Runs on hot water and heating.
- Multiloop. In addition to the above functions, it can be connected to a floor heating system.
By control system:
- Mechanical. Simple and reliable unit. Power controls are located on the panel. The temperature is controlled by a gas valve.
- Electronic. Boilers have advanced functionality, additional modes and the ability to save settings. Can be controlled remotely, some models are even controlled from a distance. Sensitive to power surges.
Types of energy from which heating units can operate:
- Gas. You can use main or liquefied fuel. Such a product is more popular due to the cheapness of gas. Requires permission to install.
- Combined. The main type is solid fuel. In the summer, when the heating is turned off, you can switch to gas.
So, you learned about the structure and principle of operation of heating equipment. Which is better to choose: convection or condensing boiler? What are the advantages of the latter?
Advantages
Let’s start with the pros.
Economical gas consumption. When compared with convection equipment, you can save up to 35% of energy. It all depends on the power of the equipment, as well as the area of u2,85bu250bthe heated room. For example, a condensing appliance will consume 3,25 kWh to heat XNUMX m². With the same area, the convection device consumes XNUMX kW / h.
Environmentally friendly. Due to the reuse of combustion products, the capacity of harmful impurities is reduced. In addition, the temperature of the gases decreases. On the one hand, the convection heater throws waste through the pipe, which contains sulfuric, nitric, phosphoric acid. On the other hand, acids that condensate still flow down the drain. So the question of environmental friendliness is debatable.
Long service life. The heat exchanger and other parts are made of materials resistant to aggressive environments. Therefore, they last longer than usual.
Cheap chimney creation. A fan is used to remove smoke, so the height of the pipe should not be the same as in atmospheric devices.
Disadvantages
Cost. A condensing unit can be 30-80% more expensive than conventional equipment. But the equipment is not bought for one year, so it is realistic to count on the payback.
Boilers are divided into three segments:
- Premium class. Includes well-known brands. The quality complies with environmental standards, the best materials are used. They have a large selection of functions and modes, which facilitates operation. Electronic control, remote.
- Middle class. The equipment belongs to the middle price category, the functionality is moderate. The control is automatic, the work is controlled by electronic sensors.
- Economy class. Korean and Slovak manufacturers are leading. Often these are products with mechanical or semi-mechanical adjustment, a standard set of functions. The huge advantage of the “economy” segment is in adapting to our latitudes: pressure drops in highways, power surges in the network.
The high price is typical not only for the devices as a whole, but also for their heat exchanger. If this unit breaks down, it will not be easy for you, because its cost is equivalent to buying a new unit. In the manufacture, silumin and steel are used, and seamless technology is also used. Therefore, clean the part in time, carry out preventive maintenance.
Installation expediency.
An important point: the boiler is effective only in low-temperature heating systems, where the supply temperature is 50–55 degrees, and the return temperature is 30–35 degrees.
Such equipment is suitable for dwellings with a system of warm floors. In another case, you will have to mount additional radiators or redraw the entire system. And this negates the savings when buying a device. The fact is that only in such conditions can condensate be produced. If you have a high-temperature circuit, you should consider purchasing a convection unit.
Problems with condensate discharge. The difficulty is in the amount of acids that the condensate contains. If you live in an apartment, then the moisture emitted by equipment up to 28 kW will be diluted with drains and go into the sewer (at this capacity, about 70 liters per day). And residents of private homes will have to think.
If drains are drained into the soil, salinization will occur and the area will not be fertile. Every day to take out to the scrap? Pretty problematic. The way out is to install an acid neutralization system.
In the West, the purchase of a catalytic converter is mandatory when using a condensing unit. What does the overall increase in the expense item mean.
The best models
We have selected the most popular models of condensing appliances, having studied user reviews.
Baxi Duo-Tec Compact 24
Technique of the fourth generation from the Compact series. These are compact attachments measuring 700x400x299 mm. Double-circuit equipment with a capacity of 24 kW. The efficiency is 97,7%.
The product is designed for heating 240 m² of area. The work is based on main gas, which is appropriate for apartments, if desired, you can switch to liquefied fuel. Suitable for residents of cottages and private houses with autonomous heating.
A closed combustion chamber and a turbocharged burner require a mains connection. The removal of gases is carried out by the fan forcibly. In the presence of electronic control, LCD display for monitoring performance. Therefore, it is recommended to connect a stabilizer.
Features:
- GAC – the combustion process is controlled automatically.
- Possibility of flame modulation 1:7.
- Stable operation at a pressure of 5 mbar.
- The steel burner automatically mixes the gas and air at the right concentration.
- The pump is equipped with an integrated air outlet.
- Automation reacts to changes in the weather by adjusting the settings.
Operating temperatures 25–80 °С. Maximum performance 13,8 liters.
Price from 50 000 rubles.
Buderus Logamax Plus GB172i-35i
First of all, the Logamax Plus GB172i-35i stands out for its unusual design. This is a non-standard metal structure, a glass facade and a huge touch screen. Black color emphasizes the strict lines of the model. Indeed, not everyone can pay for the purchase of a boiler.
Buderus Logamax has not only a stylish appearance, but also a high power of 30 kW. Therefore, it serves premises up to 300 m². The internal filling has been improved: the WB5 type heat exchanger received a 10-year warranty from the manufacturer. The control system is amazing with its abilities: the device connects to the Internet, scans weather data and adjusts its work for efficient heating.
Features:
- Aluminum alloy radiator.
- Convenient one-hand operation. Large and clear screen.
- An expansion tank of 12 liters is part of the design.
- Remote control. Connect to tablet, computer, smartphone.
- The titanium glass facade is not afraid of damage.
- Burner with modulation 1:8.
Dimensions 840x440x350 mm. The cost is from 70 rubles.
Vaillant ecoVIT VKK INT 476/4
The floor boiler is equipped with a multi-sensor system, for which the company received an award in the gas industry. The load is 47 kW. The flame in the burner is modulated from 20% to 100%. A DHW cylinder can be connected to the main circuit. The efficiency reaches 109%, taking into account the energy of the condensate.
The radiator is made of stainless steel, the burner automatically mixes air with gas. To maintain combustion, air is taken from outside or inside the room. Works even at a pressure of 3 bar in the line.
The “Anti-freeze” mode is on, the flame sensor is on. Electronic ignition. Case size 1257x570x691 mm.
Price from 130 000 rubles.
The brands of condensing units Viessmann, Wolf, Bosch, Daewoo are also popular among users. Here are the reviews they write:
Alexander
When I decided to buy a boiler, I was looking for an economical and modern model. Pay attention to the condensing heating system. However, efficiency indicators of 100-110% did not inspire confidence. Later I figured out that the calculation of efficiency takes into account the energy in the production of condensate. Another point that stopped me from buying was the need to drain water with acids. But after talking with the seller, I realized that not everything is so scary. I have been using the device for two years now, I am absolutely satisfied with the purchase.
Victoria
Having studied the information on websites and forums about condensing boilers, I could not make a decision. Confused by the fact that the moisture that is produced from gases contains acids. Some sites “intimidated” corroding plastic pipes, others, on the contrary, wrote that there was nothing to worry about. Exhausted by speculation, I turned to the manufacturer. It turned out that the content of acids is very small – pH 3-5. Diluted with waste water, the solution does not cause harm.
Moreover, condensation also accumulates in conventional appliances, which leads to corrosion. In a private house, you can organize a separate drain. So everything is solved.
Consumer reviews prove that the advantages and disadvantages of technology are very relative. If you want to buy such equipment to save money, then consider the facts. In Russia, the cost of gas is lower than the world one. Taking into account the installation (plus the arrangement of the drain, neutralizers), the savings on the condenser device will be 15–20%. Therefore, the acquisition will pay off in 10-20 years. The product is very popular in the West, because fuel is much more expensive there. As a result, the difference between convection and condensing equipment pays off in just a couple of years.
We recommend that you consult with a qualified professional before purchasing. Make cost estimates for your home. Then you will understand if the game is worth the candle.