Mainly gas boilers low power 5-7 kW is used for heating small country houses or small apartments up to 50 m². But, if you decide to purchase such a unit, you should take into account that the adjustment for heat loss can range from 10 to 30%.
A 5 kW gas boiler is designed for heating buildings that do not have a chimney. Therefore, all known models of such heating devices are equipped with a firebox closed type. They do not require a full smoke exhaust system. To remove combustion products, a coaxial type pipe will be sufficient. In most cases, it comes complete with the boiler. Such a chimney is carried out through a hole in the wall and out into the street. Best option, if it is located horizontally.
When choosing low-power devices, you should accurately calculate whether such a boiler can sufficiently heat the available area. If the structure is poorly insulated and the doors and windows are ventilated, the device’s performance of 5 kW may not be enough.
In addition, it should be taken into account that the manufacturer indicates the maximum power of the unit in the passport. And if the gas boiler constantly operates at its maximum capacity, this will quickly lead to wear and tear. Therefore, in this case, it is important to accurately determine whether the specified performance is sufficient to heat your room.
Gas boilers 5 kW power are equipped with a standard set of necessary functions and are quite easy to use. They don't have modern systems management, control and safety of operation, which are equipped with many units with higher productivity. Also, low-power devices do not have a display, control panel or the ability to connect other heating systems, for example, “warm floors”.
Favorable operating conditions for 5 kW heating boilers
Gas boilers with a capacity of 5 kW will efficiently heat a house or apartment if certain operating conditions are met:
- good wall insulation;
- no gaps in window and door openings;
- ceiling height no more than 2.7 m;
- absence of severe prolonged frosts.
Advantages and disadvantages of low-power units
The advantages of low-power units include:
- small dimensions;
- low fuel consumption with fairly high efficiency;
- affordable price;
- ease of operation;
- ease of installation.
Disadvantages of gas boilers with low productivity:
- limited functionality;
- small selection of models;
- difficult to find components;
- limited operating conditions.
Models of gas boilers with a power of 5 kW
ATEM ZHITOMIR-M AOGV 5 SN
This wall-mounted single-circuit parapet-type gas boiler has a heat exchanger made of steel. Ignition is carried out using electricity by pressing a button. The unit is equipped gas burner Italian made Polidoro. Safety is ensured using the gas valve 630 EUROSIT (Italy). The kit includes a coaxial pipe.
The boiler has the following characteristics:
- Efficiency – 90%;
- weight – 30 kg;
- warranty – 12 months;
THERMOBAR KS-GS-5 s
The presented single-circuit floor-standing model is characterized by efficiency and silent operation. If a failure occurs, the Italian EUROSIT safety system blocks the fuel supply.
The gas boiler is equipped with a stacked sectional burner made of of stainless steel, which ensures the environmental friendliness of the smoke produced and the absence of soot accumulation in the combustion chamber. The heat exchanger of the unit is made of steel. The coolant temperature ranges from 40-90ºC. The kit includes a coaxial type chimney. This boiler has connections for connecting to heating system located on both sides.
The gas unit has the following characteristics:
- Efficiency – 90%;
- weight – 40 kg;
- fuel consumption – up to 0.56 m³/hour;
- warranty – 12 months;
- country of origin: Ukraine.
The boilers are equipped with a microprocessor modulation power control system (57-100%), pre-mix burners, which guarantees minimal NOx (less than 25 ppm), CO and CO2. The boilers are equipped with a full range of interlocks and security systems, a built-in circulation pump, and a built-in storage tank (for dual-circuit models). The heat exchangers of Indurance boilers are guaranteed for 5 years.
Low-power gas boilers are often used in residential buildings. Due to the installation features, they are divided into floor-mounted and wall-mounted. To provide housing hot water and a domestic double-circuit gas boiler is used to heat the premises. In such a device, the boiler, the boiler itself, the burner and the automation system are connected. This is almost a miniature boiler room in the house.
Low-power gas boilers are installed quickly, they do not require a separate room, and are mounted on the floor or wall. Floor standing boilers more powerful, better suited as heating devices. When choosing which floor-standing double-circuit gas boiler to buy, it is recommended to focus on the heat exchanger material: cast iron, copper or steel. The best thermal conductor is copper, but it is more expensive. A household double-circuit gas boiler with a built-in boiler is suitable for country house. This model has a larger quantity in stock hot water, can operate at low pressure and produces less scale.
Dual-circuit domestic boilers They also differ in the type of gas burner, which can be atmospheric with air supply by gravity or can be pressurized. With this option, air is forced into the combustion chamber using an electric fan. The second option is more economical, as it has greater efficiency.
You can buy a floor-standing double-circuit gas boiler from a specialized organization, where specialists will help you choose the most suitable suitable model and install a water heating device in the house.
Model range of gas boilers “Indurance”
| Distinctive features of Indurance boilers: | Indurance boilers contain as standard: |
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At high efficiency Indurance boilers, operating costs are minimal. Ideal design, ease of operation and low costs guarantee savings! All equipment is certified by Gosstandart, Gosgortekhnadzor of the Russian Federation and is permitted for use in Russia
Boiler production is certified to ISO9002 standard
Gas boiler for heating a private house– this is not only a necessity, but one of the main elements comfortable stay, therefore, the choice must be approached consciously at the stage of designing the entire system as a whole. The heating equipment market does not stand still and is constantly evolving and the result of fierce competition is the availability of the widest selection of boilers various brands, configurations and modifications. Unlike owners of city apartments, who most often receive a boiler after the fact, the owner of a private house has the opportunity to choose a unit at almost any stage of designing his home.
From the author: the purpose of this article is to get acquainted with modern heating equipment, its main differences, variety and applicability. We are not representatives of any boiler manufacturer, but are engaged in diagnostics and repair of electronics of gas units and will try to make this review as practical and unbiased as possible.
Criteria for choosing a gas boiler
One of the main selection criteria gas boiler is the required power and the home's need for hot water. Ideally, the required boiler power is selected based on the thermal calculation of the building that will be heated by it. In the process of thermal calculation, heat losses rooms, number of windows, doorways, ceiling heights, wall materials and characteristics of the selected thermal insulation.
There is an opinion that you can select the power of the unit at the rate of 1 kW per 10 square meters area, but this value is quite arbitrary. Modern thermal insulation materials, plastic windows and insulated doors significantly increase class energy efficiency buildings, and this figure can be reduced by 20-30%.
Significantly overestimating the boiler power can lead to a decrease in its operating efficiency. Modern gas boilers allow you to regulate power in a fairly wide range, but it should be borne in mind that the maximum efficiency and economy of the boiler will be achieved when it operates at rated power. Full time job boiler on
the lower power limit reduces the efficiency of the unit by approximately 12-15%. Information on the efficiency value at different modes work is usually indicated in the passport or instructions for the device. Overestimating the boiler power also risks turning the device on and off too frequently, which negatively affects the actuators and electronics.
When choosing power, some experts recommend taking into account the need to prepare hot water and increasing the power by 20%, or even twice. Naturally, when choosing a gas boiler for heating a private house, it is assumed that the residents will also need hot water, but it would be more correct to be guided not by the power, but by the number of hot water supply points and their distance from the boiler room.
Often the final power and type of boiler are selected based on the needs for hot water preparation.
Depending on this criterion, there may be several options:
double-circuit gas boiler
boiler with built-in boiler
single-circuit boiler and boiler indirect heating
Double-circuit gas boiler
Double-circuit gas boilers are designed to heat the coolant in the heating system and, if necessary, prepare hot water, i.e. they implement two independent circuits. Depending on the type of boiler, double-circuit models can have one heat exchanger (primary) and two - an additional plate heat exchanger for preparing hot water. When choosing such a boiler, you should pay attention to the boiler’s performance in DHW mode. On average, the water consumption of one water tap at a comfortable pressure and average pressure will be about 8-10 liters per minute.
Based on this, for example, a 24 kW double-circuit boiler will be able to provide approximately 2 water points, because the performance of the heat exchanger in DHW mode in most cases will be 14-15 liters per minute. And such productivity will be at a temperature delta of 25 degrees; at a temperature delta of 35 degrees, this value will be significantly less - around 10 liters per minute. Delta means temperature difference cold water and the required heating temperature. Comfortable temperature DHW is about 40 degrees, therefore, at a temperature of incoming cold water of about 5 degrees (in winter period) – the delta will be exactly 35. For example, we give these characteristics for some of the most well-known models:
With an increase in boiler power, these figures will not increase significantly. For models 32-36 kW this is approximately 15-16 l/min, and for 38-40 kW 18-19 l/min. Therefore, it is obvious that a double-circuit boiler with secondary heat exchanger can be considered mainly for small private houses or apartments with an area of up to 120 square meters with two, maximum three water collection points. Double-circuit boilers are separate devices and are not intended for collaboration with boilers.
To summarize, we can highlight the following features of dual-circuit models:
versatility (heating and hot water at the same time)
dimensions (can be mounted in kitchen cabinet)
ease of installation and operation
lower value (cost) of initial costs
Boiler with built-in small volume boiler
Such boilers have some advantages over typical double-circuit ones: instead of a flow-through heat exchanger, a small-capacity boiler is installed (usually 40-60 liters) and this means that there is always a small supply of hot water. Firstly, residents practically do not have to wait for the water to heat up for the first time. Secondly, the boiler will turn on less often - it happens that you need to briefly open the tap to rinse the cup. In this case, the double-circuit boiler will turn on and heat the water at full power; the option with a built-in boiler will turn on only when the temperature of the reserve water drops below the set one. Fewer switches mean longer service life of actuators.
For example: the Ariston CLAS B EVO 24 FF model (built-in tank of 40 liters) already has a performance in DHW mode of 16 liters per minute at a delta of 35 degrees and 19 liters per minute at a delta of 30 degrees 10 minutes after switching on!
Obviously, such boilers have a greater degree of comfort, but are significantly more expensive. Also, they do not have problems with scale formation, that is, they are less demanding on water quality. When choosing a boiler for a private home, you should pay attention to performance in DHW mode and ease of maintenance.
Single-circuit boiler and indirect heating boiler
An indirect heating boiler is a container for storing water that does not have its own heating element, and heating occurs due to external sources(for example, a boiler or solar panels). According to many experts, the use of a single-circuit boiler and boiler in a heating scheme is most preferable. This scheme differs from the previous version in the volume of the boiler itself in the direction of increase. The boiler is selected based on the hot water needs of the residents of a private house. There are various methods for choosing, calculators - this is the topic of a separate review. Individually, it is necessary to determine the maximum possible one-time water consumption, for example, in the morning, and select a container of the required volume. The performance of the boiler will depend on the power of the boiler, because the power of the boiler itself is limited by the power of its coil. The boiler volume is selected based on peak water consumption values. If we average, we can give the following recommendations: up to 80 liters for a family of 1-2 people, up to 150 liters for a family of 3-4 people and from 200 liters for families of more than 5 people. In non-standard cases, it is necessary to carry out design calculations.
Thus, we get the following advantages of using a boiler:
constant supply of hot water ( maximum comfort)
lower hydraulic resistance compared to a plate heat exchanger
reducing the number of boiler starts
reducing water consumption (no need to drain water while waiting for heating)
no scale formation (does not interfere with regular maintenance)
Some heating equipment manufacturers have ready-made options boiler + boiler, which are installed in a single system.
So, in the end, we select the boiler according to the heat losses of the house, the boiler according to the needs for the amount of hot water.
In addition to the main performance characteristics boilers have a number of other differences: material of manufacture and type of heat exchanger, type of combustion chamber, installation method.
Based on the installation method, there are floor-standing and wall-mounted boilers. Wall-mounted boilers are characterized by their compact size, light weight and versatility; they are used when there is no separate room for installation of a gas boiler. Floor-standing models are equipped with heat exchangers made of cast iron (therefore, they are heavy) and require certain requirements from the room during installation. Distinctive feature of such boilers is their high reliability. The cast iron heat exchanger is highly resistant to corrosion and has a long service life. The disadvantages are fragility and heavy weight.
Heat exchangers of wall-mounted boilers can be made of steel, copper, aluminum alloy or stainless steel. Steel heat exchangers they are the cheapest and have a number of disadvantages, such as lower efficiency, a tendency to deformation and have a shorter service life. Copper heat exchangers have significantly greater thermal conductivity, corrosion resistance and lower weight.
Bithermic heat exchanger
Worth considering separately design feature gas boilers with bithermic heat exchanger. In “bithermics”, heating of the heating fluid and running water occurs in a single primary bithermic heat exchanger (there is no secondary one). When the boiler needs to heat the heating system, the circulation pump turns on when required DHW heating– the pump is turned off and all power is transferred to the flowing water in the same place tap water. The heat exchanger itself is a pipe-in-pipe structure (one is heating, the other is DHW). The advantage is low price, but water treatment of the water passing through the heat exchanger becomes an important necessity. Limescale, which actively forms on the walls when high temperatures operation can significantly reduce service life.
Atmospheric and turbocharged gas boilers
According to the method of removing combustion products, gas boilers are divided into atmospheric, where smoke is removed from the combustion chamber due to natural draft in the chimney, and turbocharged, in which combustion products are removed forcibly using a fan.
Gas boilers with a fan are more expensive, but more economical and have greater efficiency. To install such a boiler, you do not need a classic chimney; it is enough to use coaxial chimney(pipe in pipe), in which air is supplied and exhausted through one common pipe, which can be removed from the room through the wall.
Modern fans with adjustable speed allow you to achieve significant savings and, in combination with a modulating gas burner, regulate the boiler power over a very wide range, as well as obtain high efficiency in low power modes.
Condensing boilers
Everyone roughly represents the process of heat transfer in a conventional gas boiler: the heat exchanger is located directly above the burner and when the gas is burned, heat is transferred to the coolant. During combustion of the gas-air mixture, formation occurs carbon dioxide, water and heat generation. The remaining heat that the heat exchanger did not have time to accept goes into the chimney, while the temperature of the flue gases can range from 140 to 170 degrees.
With this scheme a large number of the heat simply flies out the pipe. This is due to the fact that combustion products contain approximately 10% water in a gaseous state, i.e. in the form of steam and manufacturers are trying in every possible way to avoid condensation of this steam inside the boiler or chimney. The design of a traditional boiler is designed to prevent the formation of condensation, because condensate is water only in a simplified form. In reality, combustion products contain harmful impurities that form an aggressive mixture of acids (nitric, sulfuric, coal), which lead to rapid wear of boiler elements.
The process of condensation formation begins when the combustion products are cooled to approximately 55-57 degrees. Therefore, the solution to extract additional heat is to cool the combustion products to the point where condensation forms inside the boiler and control this process. For maximum heat transfer to the coolant, it is required big square heat exchanger and creating conditions for the formation of condensate inside this heat exchanger. In addition, the condensate, when cooling, gives additional heat, which, in fact, is transferred to the coolant, flowing down the walls. That is why marketers often indicate the efficiency of such boilers as more than 100%, adding the effect of heat transfer by condensate to the efficiency of a traditional boiler.
Example: Baxi LUNA DUO-TEC 1.24 GA. Maximum power 24.7 kW, and the minimum power is only 3.7 kW!!!
In addition to heat removal efficiency condensing boilers can regulate power over a very wide range. This is especially true in middle lane, where the average annual temperature ranges from 0 to 5 degrees. Therefore, such a boiler will be much more economical than a traditional one in the off-season, when the use of the rated power of the boiler is not required.
In addition to all the advantages, it is worth noting that to get maximum opportunities condensing boiler necessary low temperature mode operation (supply temperature less than 50 degrees), and this is not always possible. Since the boiler, in fact, is additionally a generator of condensate, it must be disposed of in a country house using septic tanks - this will have to be taken care of additionally.
In a country house, insects can also become a real problem for such a boiler. The temperature of the exhaust gases is low and therefore attracts insects, and in the case of a coaxial chimney, x will be continuously sucked into the combustion chamber.
Conclusion
In this review we looked at the main differences gas installations presented on the market, reviewed standard schemes applicability. Choosing a gas boiler can be a difficult task; which one should you choose - Ariston, BAXI, Vaillant or Protherm? Let's give some advice.
Choose boilers popular brands, widely distributed in the market of a particular region. Purchasing products from little-known manufacturers may limit the life of the boiler before the first breakdown.
Pay attention to the materials and manufacturers of the main components of the boiler (hydraulic group, circulation pump, heat exchanger). Preference should be given to well-known global brands and durable materials.
Expansion tank. It is worth seeing whether the volume of the built-in expansion tank will be sufficient for your conditions, because in different boilers of the same power it can differ in the range from 6 to 10 liters. If the heating system provides its own expansion tank, then the recommendation can be ignored.
Be sure to evaluate the cost of boiler ownership and availability service department and spare parts. You can compare prices for the main components: heat exchanger, electronic board, fan and others. IN different regions The availability of spare parts may vary, so you should give preference to the most common brands, which will not cause problems in the event of a breakdown, for example, during the heating season.
When choosing, compare technical equipment different models: the presence of self-diagnosis functions, anti-freezing, post-circulation, power adjustment ranges, the presence of a heated floor mode (if necessary) and the ability to connect programming options and weather-dependent automation.
If you choose a single-circuit boiler for antifreeze as a coolant, check the possibility of its use. Some manufacturers prohibit the use of antifreeze in their boilers.
Be sure to review the product warranty terms. In some cases, the warranty may be calculated from the date of manufacture of the product, and if you are sold a boiler that has been in storage for two years, you will lose the lion's share of the warranty period.
As for reviews, we do not recommend using them as the final truth. Equipment operation histories may be different and depend on specific conditions, region, water hardness, power supply quality, and the competence of the designer and installer. Some people treat things with care, observe intervals Maintenance and operating rules, others believe that you can not approach the boiler for 10 years and everything should work. On the Internet you can often find frankly customized reviews or reviews written for search engines, so they are often biased and have absolutely no value. A gas boiler has not been a luxury for a long time and is used everywhere, therefore, it is better to take advantage of the reviews of the owners who are likely to be found in the immediate vicinity.
We hope that this material will help you in choosing a gas boiler for heating a private home; we also recommend watching a video with recommendations from professionals.