Includes not only heating equipment, but also a set of certain measures for its installation and assembly. Correct and quality installation will undoubtedly affect the operation of the boiler in the future.
There are a number of standards and regulations for the installation of gas condensing boilers. First of all, you need to know that the installation of a condensing boiler requires a permit from a gas inspection. When connecting the boiler, the technical rules for connecting the gas and the necessary safety measures must be observed.
This is a prerequisite to prevent damage to the boiler and possible injury to people.
It is even better if the installation and assembly of the condensing boiler is carried out by qualified specialists.
The best place to install is a non-residential area. If the house does not have such a separate room, then the boiler can be installed in the kitchen. Ideally, the walls of the room where the boiler will be installed should be tiled, but in no case with fire hazardous materials. The floor should be covered with a non-combustible covering, it is desirable that there is a sewerage system in the room. Heating boilers condensing ones provide for the presence of hoods in the room where they are installed.
The wall-mounted condensing boiler is fixed to the wall with special hooks using dowels. Correctly, if the condensing boiler is located in such a way that its lower part protrudes from the wall more than the upper one.
If, on the contrary, it means that the boiler is not secured correctly. The installation of the condensing boiler is done in such a way that there is no tilt, otherwise it may lead to a short circuit.
Therefore, when attaching the boiler to the hooks, it is necessary to very well check the verticality of the boiler so that it does not tilt forward or to the side.
There are many options for connecting a chimney to a condensing boiler. The main requirement for condensing boilers is the tightness of the joints of the chimney elements.
In general, the chimney design of condensing boilers does not differ much from the chimney design of conventional gas boilers.
Features of chimneys for condensing boilers:
The condensing boiler provides for a system of operation in which condensate is formed from the water vapor contained in the combustion products.
Depending on the power and temperature regime, up to 50 liters of condensate of a low acidity level can form per day. This allows it to be drained into a household waste siphon and not harm the environment.
However, there are some errors when:
The condensing boiler provides for the presence of all the above points, and also provides for the observance of all technical regulations and standards for installation and assembly.
Often, private houses do not have access to centralized systems, so the owners have to independently decide how to implement ...
The users of our portal have a unique opportunity - to follow how, within the framework of the project with FORUMHOUSE, we, with our partners, are building a comfortable and energy-efficient Vacation home... For this, when building a cottage, the most modern materials and technology.
The USP was chosen as the foundation, and the heated floor was used for the heating system. In addition, a wall-mounted condensing gas boiler became the boiler room. The technical specialist of the company will tell you in the format of a master class about why this particular equipment was chosen for our project, and what are the advantages of its work.
Before we talk about the nuances of condensing technology, we note that an energy efficient, and therefore comfortable and economical country house is a balanced structure. This means that, in addition to the closed thermal insulation loop, all elements of the cottage, including engineering system, should be optimally matched to each other. Therefore, it is so important to choose a boiler that goes well with the low temperature heating system"Warm floor", and will also reduce the cost of purchasing energy in the long term.
Sergey Bugaev Ariston Technician
In Russia, in contrast to European countries, condensation gas boilers less common. In addition to environmental friendliness and greater comfort, given view equipment allows you to reduce heating costs, because such boilers operate 15-20% more economically than conventional ones.
If you look at the technical characteristics of condensing gas boilers, you can pay attention to the efficiency of the equipment - 108-110%. This is contrary to the law of conservation of energy. While, indicating the efficiency of a conventional convection boiler, manufacturers write that it is 92-95%. Questions arise: where do these numbers come from, and why does a condensing gas boiler work more efficiently than a traditional one?
The fact is that such a result is obtained thanks to the technique heat engineering calculation, used for conventional gas boilers, does not take into account one important point evaporation / condensation. As you know, during the combustion of fuel, for example, main gas (methane CH 4), thermal energy, and also carbon dioxide (CO 2), water (H 2 O) in the form of steam and a number of other chemical elements are formed.
In an ordinary boiler, the temperature flue gas after passing through the heat exchanger, it can reach 175-200 ° C.
And water vapor in a convection (conventional) heat generator actually "flies into the pipe", taking with it into the atmosphere a part of the heat (generated energy). Moreover, the amount of this "lost" energy can reach 11%.
To increase the efficiency of the boiler, it is necessary to use this heat before it leaves, and transfer its energy through a special heat exchanger to the coolant. To do this, you need to cool the flue gases to a temperature of the so-called. “Dew point” (about 55 ° C), at which water vapor condenses with the release of useful heat. Those. - use the energy of the phase transition for maximum use the calorific value of the fuel.
We return to the calculation method. The fuel has a gross and net calorific value.
The efficiency of the boiler is expressed in the amount of thermal energy received during the combustion of fuel and transferred to the coolant. Moreover, indicating the efficiency of a heat generator, manufacturers can calculate it by default using the method using the lowest calorific value of the fuel. It turns out that real efficiency of the convection heat generator actually is about 82-85% , a condensation(remember about 11% of the additional heat of combustion, which it can "take" from the water vapor) - 93 - 97% .
Hence, the figures for the efficiency of the condensing boiler appear, exceeding 100%. Due to its high efficiency, such a heat generator consumes less gas than a conventional boiler.
Sergey Bugaev
Maximum efficiency condensing boilers ensure, if the temperature of the return line of the coolant is less than 55 ° C, and these are low-temperature heating systems "warm floor", "warm walls" or systems with an increased number of radiator sections. In conventional high temperature systems, the boiler will operate in condensing mode. Only in severe frosts will we have to maintain high fever coolant, the rest of the time, with weather-dependent regulation, the coolant temperature will be lower, and due to this, we will save 5-7% per year.
The maximum possible (theoretical) energy saving when using the heat of condensation is:
So, we have dealt with the theoretical part. Now we will tell you how the design features of a condensing boiler affect its efficiency and durability. At first glance, it seems that it is possible to use the additional energy of water vapor hidden in the flue gases in a conventional boiler, specially "driving" it into a low-temperature mode of operation. For example, by connecting the boiler (this is wrong) directly to the underfloor heating system or by significantly lowering the temperature of the coolant circulating in the radiator heating system. But, we have already written above that during the combustion of the main gas, a whole "bunch" of chemical elements is formed. Water vapor contains: carbon dioxide and carbon monoxide, nitrogen oxides, as well as sulfur impurities. During condensation and the transition of vapor from a gaseous to a liquid state, these impurities appear in water (condensate) and a weak acidic solution is obtained at the exit.
Sergey Bugaev
The heat exchanger of a conventional boiler will not withstand long-term operation in an aggressive chemical environment; over time, it will rust and fail. The heat exchanger of the condensing boiler is made of materials that are resistant to corrosion and acidic environments. The most resistant material is stainless steel.
Only durable and wear-resistant materials are used in the construction of the condensing boiler. This increases the service life and reliability of this equipment, and also reduces the cost of service.
In addition, increased requirements are imposed on other structural elements condensing heat generator, because it is required to cool the flue gases to the required temperature. For this, the boiler is equipped with a high modulation forced draft burner. Such a burner operates in a wide power range, which makes it possible to optimally regulate the heating of water. Condensing boilers are also equipped with automation that ensures accurate maintenance of the combustion mode, temperature of flue gases and water in the return line. Why are they put circulating pumps, smoothly changing the force of the pressure of the flow of the coolant, and not as simple 2-speed and 3-speed ones. With a conventional pump, the heating medium flows through the boiler at a constant speed. This leads to an increase in the temperature in the "return", an increase in the temperature of the flue gases above the dew point, and, consequently, a decrease in the efficiency of the equipment. It is also possible overheating of the heating system (warm floor) and a decrease in thermal comfort.
An important nuance: the burner of a conventional boiler cannot operate at a power lower than 1/3 of the maximum (nominal) power of the heat generator. The burner of the condensing boiler can operate at a power of 1/10 (10%) of the maximum (nominal) power of the heat generator.
Sergey Bugaev
Consider the following situation: the heating season has begun, the outside temperature is -15 ° C. The power of a conventional boiler installed in a house is 25 kW. The minimum power (1/3 of the maximum) at which it can operate is 7.5 kW. Let us assume that the heat loss of the building is 15 kW. Those. the boiler, continuously working, compensates for these heat losses, plus there is a power reserve. A few days later there was a thaw, which, you see, often happens over the winter. Eventually outside temperature now around 0 ° C or slightly lower. The heat loss of the building, due to the increase in temperature outside, has decreased and is now about 5 kW. What happens in this case?
An ordinary boiler cannot, working in continuous mode, to issue 5 kW of power required to compensate for heat loss. As a result, it will go into the so-called cyclical mode of operation. Those. will constantly turn on and off the burner, or the heating system will overheat.
This mode is unfavorable for the operation of the equipment and leads to its accelerated wear.
A condensing boiler, with the same power and in a similar situation, will quietly deliver 2.5 kW of power (10% of 25 kW) in continuous operation, which directly affects the service life of the heat generator and the level of comfort in a country house.
The condensing boiler, supplemented by weather-dependent automation, flexibly adjusts to changes in temperature conditions during the entire heating season.
Modern automation makes it possible to significantly simplify the boiler control process, including remotely, using a special mobile app for smartphones, which improves the usability of the equipment.
We add that the heating season in Russia, depending on the region, averages 6-7 months, starting in autumn, when it is not very cold outside, and lasts until spring.
About 60% of this time, the average daily temperatures outside are kept around 0 ° C.
It turns out that the maximum power of the boiler may be required only in a relatively short period of time (December, January), when real frosts were established.
In other months, the boiler is not required to reach the maximum operating mode and increased heat transfer. Consequently, a condensing boiler, unlike a conventional boiler, will work effectively both with temperature drops and with a little frost. At the same time, gas consumption will decrease, which in tandem with low temperature system heating (underfloor heating) will reduce the cost of purchasing energy.
Even when using a condensing boiler together with a high temperature radiator heating this equipment works 5-7% more efficiently than traditional equipment.
Sergey Bugaev
In addition to efficiency, an important advantage of condensing boilers is the ability to obtain high power with a compact size of equipment. Condensing gas boiler in wall-mounted especially relevant for small boiler rooms.
In addition, the condensing boiler has a turbocharged burner, which makes it possible to dispense with the standard expensive chimney and simply lead the coaxial chimney through the hole in the wall. This simplifies the installation of equipment or the installation of a new condensing boiler to replace the old one, when renovating an existing heating system.
Frequent questions from consumers: what to do with condensate obtained during the operation of the boiler, how harmful it is, and how to dispose of it.
The amount of condensate can be calculated as follows: 0.14 kg per 1 kW * h. Therefore, a condensing gas boiler with a capacity of 24 kW when operating at 12 kW of power (since most during the heating period, the boiler works with modulation, and the average load on it, depending on the conditions, can be below 25%) on a rather cold day, it produces 40 liters of condensate at low temperature mode.
The condensate can be discharged into the central sewerage system, provided that it is diluted in a ratio of 10 or better 25 to 1. If the house is equipped with a septic tank or a local treatment plant, neutralization of the condensate is required.
Sergey Bugaev
The neutralizer is a container filled with marble chips. Filler weight - from 5 to 40 kg. It must be changed manually on average once every 1-2 months. Condensate, usually passing through the neutralizer, flows by gravity into the sewer.
This modern equipment is distinguished by its reliability, economy and efficiency of work. Emissions are also reduced harmful substances into the atmosphere, which is especially important when environmental standards are tightened. In addition, the installation of this type of heat generator, by reducing gas consumption, will reduce heating costs in the long term and increase the level of comfort in a country house.
It must be made of materials that are highly resistant to acid corrosion. It is one thing when hot combustion products pass through the pipe, and quite another when condensate forms in it, concentrated acid with a pH of 3 to 5.
This tank (boiler) must be equipped with a siphon water seal filled with water to prevent flue gases from entering the drain line.
Insulated. Photo: Navien
The flue gas temperature is low (about 55 C), three times lower than the flue gas from a conventional boiler (180 C). Because of this, the natural draft of the chimney, as a rule, is not enough, therefore forced draft is used. The boiler fan helps to remove flue gases from the boiler.
Due to the forced draft, the chimney must be sealed along its entire length (for example, lip seals are used). Otherwise, part of the flue gases will enter the room.
Coaxial. Photo: Protherm
For normal operation of the condensing boiler, it is necessary to organize a constant air flow to it. This can be done in several ways, for example, by taking air from the room, if there is a sufficient supply of air in it. If the supply air is insufficient, the air supply is organized through the same chimney, which is usually done in the form of a concentric pipe for this ( coaxial chimney). By inner pipe street air enters inside, and flue gases are discharged outside.
Compact boiler with coaxial chimney. Photo: Boris Bezel
The chimney length cannot be arbitrarily long, it is determined by the fan power of a specific boiler model. For each model of a condensing boiler, it has its own, and is indicated in technical characteristics products. For example, the De Dietrich VIVADENS MCR-P 24 model is recommended to be connected to a coaxial chimney with a horizontal end and an air duct diameter of 60 mm and for flue gases 100 m. And the length of this chimney should not exceed 6 m if it has a horizontal end (outlet the pipe section goes horizontally through the wall of the house) or 20 m if the coaxial chimney has a strictly vertical structure.
The editors would like to thank De Dietrich for their help in preparing the material.
In European countries, traditional (Convection) boilers have long been abandoned. What is the reason for this approach? Europeans are solid people and know how to count the benefits, but if they use condensing boilers, then there is a benefit here. How can it be expressed?
These indicators show why practical Europeans opt for condensing boilers, although they are somewhat more expensive than usual. In Russia, according to the owners of such boilers, their payback due to gas savings comes on 2 – 4 year of operation.
The use of a condensing boiler in the heating system must be considered in the project. Since it differs significantly from the usual wiring, the diameter of the pipes and the peculiarity of the chimney.
As a rule, for heating private houses they use wall-mounted boilers... Their power is sufficient to heat a house, and their compact size allows it to be located in any convenient place; no separate boiler room is required. For example, a boiler with dimensions of only 589x368x364 is able to heat a house with an area of up to 240 m².
Installation of condensing heating boilers is possible on any reliable base. For this, either the fasteners that come with the kit are used, or a mounting frame is made. The use of such a frame allows you to organically fit this boiler into any interior.
Having fixed the boiler on the wall, proceed to the connection of communications in accordance with the corresponding diagrams. Carbon monoxide emissions are carried out through the chimney, the branch pipe must be insulated and there must be no flammable surfaces nearby.
It is more reasonable to use such a highly efficient boiler with systems that also have high performance. For example, with radiators Kermi that have the most high level heat transfer and heating system known as the Tichelmann loop.
Heating installation with a loop has a number of advantages:
Balance of the system. No additional regulators required.
High efficiency due to equal water flow throughout the system.
Uniform heating of radiators.
These effects are achieved due to the fact that the return heating line starts from the first radiator, reaches the final one, and from there is fed to the boiler. As a result, all radiators function as a single one and, regardless of the distance from the boiler, they warm up in the same way.
From the planning instructions for condensing boilers Buderus(Germany).
Complies with SNiP 41-01-2003 clause 6.4.1 PIPELINES
: "...Polymer pipes used in heating systems together with metal pipes (including in external heat supply systems) or with devices and equipment that have restrictions on the content of dissolved oxygen in the coolant, must have an oxygen permeability of no more than 0.1 g / (m3
∙ day)..."
VITODENS Gas condensing boilers
Design Instruction
Bosch Condens 3000 W
- Possibility of direct connection to the underfloor heating system
Other model
BoschCondens 5000 W Maxx
Possibility of direct connection to the underfloor heating system
Without the required minimum flow rate of circulating water
High quality components such as plasma polymerised aluminum heat exchanger and robust design make the Condens 5000 W Maxx not only extremely reliable but also extremely robust. Thanks to the innovative Flow Plus technology No minimum value water pressure through the heat exchanger ... For this reason, complete hydraulic system not required.
About anti-diffusion layer (oxygen barrier):
"... This result once again confirms erroneousness of the widespread statement: "Pipes of small diameters do not have to be reinforced or protected from oxygen ingress into the coolant, since the flow of oxygen through the wall of such pipes can be neglected." Proponents of this point of view urge not to reinforce with aluminum and not to cover with an AVOH layer (anti-diffusion layer for PEX pipes)
and PPR small diameter pipes. However, it is precisely such pipes that stand, for example, in front of steel panel radiators (the thickness of the steel wall is 1.2 mm). Therefore, it is necessary to reinforce small and large diameter pipes with aluminum for heating systems. Moreover, for small-diameter pipes, this rule is more important than for large-diameter pipes, where calculation and reference to a specific application scheme is required.
For example, at D = 2x10-11 m2 / s (oxygen permeability of polypropylene) and ∆сО2 MAX = 270 g / m3 (approximate oxygen content in the atmosphere)
Q / V = 1.9٠10-8 / DN2 (g / s٠m3) or 1.6٠10-3 / DN2 (g / day٠m3)
for DN20mm, we get 4 g / m3 of oxygen per day - in other words, the formation of 30 g of rust is possible. One meter of DN20 PN20 pipe (SDR = 6) contains 2.2x10-4 m3; accordingly, a maximum of 8.8x10-4 g / day will pass through this running meter of the pipe into the coolant. oxygen.
For example, if the heating system is made of polypropylene pipe PN20 (unreinforced or reinforced with fiberglass), the volume of the heating system is 100 liters, there is a wall-mounted boiler with an aluminum-copper heat exchanger and a heating temperature of 80 C ° and steel panel radiators, and the pipe capacity is 50 liters, then per day for a typical set of pipes of different diameters with SDR = 6 will pass into the coolant about 0.1 g of oxygen; in terms of a year, this is 37 g of oxygen, or 250 g of rust obtained in steel panel radiators(which are very likely to flow after a year or two of operation).
The objectives of this article do not include an accurate quantitative analysis of oxygen permeability, but the example given allows you to solve the frequently asked question: “How much oxygen does plastic pipe? Is it a lot or a little? " It seems that we have given a very specific answer. In conclusion, we note that a lot of substantive works have been written on this topic, but the conclusions of readers or companies supplying similar products to the market do not always correspond to the analysis carried out in these articles...."
