Air heating of a private country house: device principles, equipment selection and calculation

How to make air heating in a private house with your own hands

Design and calculation of an air heating system

Before installing air heating with your own hands, you need to consider its scheme and design for a particular private house. To do this, an approximate draft of such a system is drawn up on paper.

Then, depending on the heating requirements in a particular building, parameters such as:

• intensity of heated air injection;
• optimal power of the heat generating installation to heat the premises of the corresponding area to the required temperature;
• section of air ducts;
• aerodynamic features;
• the amount of heat loss on the surfaces of the premises.

It is advisable to coordinate a preliminary scheme with a full set of components that meets all requirements with a specialist in order to avoid any errors and shortcomings that can lead to drafts, noise or vibration in the room.

Professionals can also help you choose the optimal model of a heat generator so that it provides a comfortable temperature and does not overheat.

It is best to mount the equipment in a separate, pre-designated room.

Air heating systems

There are several types of air heating structures depending on their parameters.

According to air circulation, they are:

• with the natural flow of air masses;
• with forced air movement under the influence of pressure created by the fan.

Size and scale:

• local, designed to heat one or two rooms in a small private house;
• central - for heating multi-storey buildings and large warehouse or factory hangars.

According to the heat transfer implementation scheme:

• supply air, which draws into the room and heats the outdoor air;
• recirculation, that is, the same air moves, cooling and heating inside the room;
• with combined recirculation, when indoor air and fresh air from the street are combined.

By location in the room:

• suspended;
• outdoor units.
• Choice of heat source.

The source of thermal energy is always the heart of the entire heating system, therefore, the comfortable temperature of the premises of a private house depends on its type, power and design. There are two types of heat generators: mobile and stationary.

The first are represented by gas mobile heat generators, which are large in size. They are used for heating large industrial premises, for example, factory floors.

The second ones have an isolated combustion chamber and are designed for installation in special rooms with a smoke exhaust system. They are produced by manufacturers in two versions: as floor or suspended equipment. The second type of construction is called a heater, that is, it performs the function of heating only one room.

They are installed in country country houses, since such a device can warm up a small rear area in just a few hours.

The suspended structure is compact and produces a minimum of noise during operation. It is made of materials that conduct heat poorly, so it is safe to use even next to wooden walls.

The floor unit is much more powerful and larger, so with it you can even heat a wooden cottage with several floors.

Air source heat pumps for heating

Today, the use of heat pumps instead of boilers as sources of heat in the house is becoming more and more important. The cost of such installations extracting thermal energy from the environment is becoming more affordable, although it is still very far from ideal.

The principle of this kind of heating devices is similar to the operation of heating Split systems.Air having a temperature above absolute zero, in any case, has thermal energy, which such a pump takes from it, making it even colder outside.

The heat thus obtained is transferred to the internal air of the room, being distributed over its entire area.

This is a fairly efficient system because the electricity costs for the operation of the fans and the compressor are only 1/3 of the heat received from the air. Therefore, a heat pump is one of the best options for heating a private house, although the most expensive.

Mounting equipment

Self-installation of an air heating system in a private house requires the purchase of equipment included in it: air ducts boxes or tin pipes, heat generating installation, fan, sleeves for outdoor air intake and decorative grilles.

The choice of pipes for wiring

The final result depends on the quality of each system part, which is to save and save heat, so the longest elements - pipes - must also be given some attention.

From a technological point of view, pipes and fittings must have the following qualities:

• strength;
• ease;
• suitability for repair;
• tightness;
• low noise level.

Low cost is also an important component when choosing, because heating system equipment requires a large number of products for various purposes. Polypropylene pipes - the best option for self-assembly of the heating system

You can learn how to use a soldering machine for sewing pipes in 10 minutes

Polypropylene pipes - the best option for self-assembly of the heating system.You can learn how to use a soldering machine for sewing pipes in 10 minutes

Now it is unlikely that anyone will undertake the installation of wiring from metal pipes. Steel, copper and galvanized products are becoming a thing of the past, giving way to cheaper and more functional counterparts.

The best alternative are polymer products. which can be divided into three groups:

• polypropylene;
• metal-plastic.

The advantages of polypropylene pipes are low cost, ease of welding, long service life. Minus - lack of elasticity. When replacing a pipe, you will have to change the whole fragment from connection to connection.

On a long section of the pipeline, polypropylene pipes sag, as they have an expansion of 6 mm / 5 m. Strong fixation is provided with brackets or clips mounted in the wall at intervals of 1-1.1 m

Durable metal-plastic pipes are resistant to sudden changes in temperature. Able to serve without major repairs up to 30 years. The weak point is the connecting elements - fittings with an unreasonably narrowed flow area. In the event of freezing of the coolant, a breakthrough is likely.

When choosing pipes, be guided by the main technical indicators of the equipment and the type of coolant.

Theoretical horseshoe - how gravity works

The natural circulation of water in heating systems operates due to gravity. How does this happen:

1. We take an open vessel, fill it with water and begin to heat it up. The most primitive option is a pan on a gas stove.
2. The temperature of the lower liquid layer rises, the density decreases. The water becomes lighter.
3. Under the influence of gravity, the upper heavier layer sinks to the bottom, displacing the less dense hot water. The natural circulation of fluid begins, called convection.

Example: if you heat 1 m³ of water from 50 to 70 degrees, it will become 10.26 kg lighter (below, see the table of densities at various temperatures). If heating continues to 90 °C, then the cube of liquid will lose 12.47 kg, although the temperature delta remains the same - 20 °C. Conclusion: the closer water to boiling pointthe more active the circulation.

Similarly, the coolant circulates by gravity through the home heating network. The water heated by the boiler loses weight and is pushed up by the cooled coolant that has returned from the radiators. The flow velocity at a temperature difference of 20–25 °C is only 0.1…0.25 m/s versus 0.7…1 m/s in modern pumping systems.

The low speed of fluid movement along highways and heating devices causes the following consequences:

1. The batteries have time to give off more heat, and the coolant cools down by 20–30 °C. In a conventional heating network with a pump and a membrane expansion tank, the temperature drops by 10–15 degrees.
2. Accordingly, the boiler must produce more heat energy after the burner starts. Keeping the generator at a temperature of 40 ° C is pointless - the current will slow down to the limit, the batteries will become cold.
3. To deliver the required amount of heat to the radiators, it is necessary to increase the flow area of ​​the pipes.
4. Fittings and fittings with high hydraulic resistance can worsen or completely stop gravity flow. These include non-return and three-way valves, sharp 90° turns and pipe constrictions.
5. The roughness of the inner walls of pipelines does not play a big role (within reasonable limits). Low fluid velocity - low resistance from friction.
6. A solid fuel boiler + gravity heating system can work without a heat accumulator and a mixing unit. Due to the slow flow of water, condensate does not form in the firebox.

As you can see, there are positive and negative moments in the convection movement of the coolant. The former should be used, the latter should be minimized.

House types

Price from 1,600 rubles/m2

The main advantages of using this system are:

• High efficiency of air heating. Thermal energy is transferred directly from its source to the premises. Thus, an additional link is eliminated - the coolant, for constant maintenance, the temperature of which requires additional energy
• Possibility of year-round operation of the heating system (in summer - in ventilation or air conditioning mode)
• Independence from outside temperature. At strong negative temperatures in the water heating systems of a country house, the coolant may freeze. With air heating, this situation is excluded.
• The ability to quickly turn on and off the system without complex and lengthy preparatory procedures
• Heating a house in which there is no liquid coolant eliminates the occurrence of emergencies due to leaks or breakage of radiators, pipes
• Small inertia of the system. If the power of the heat generator is calculated correctly, then the air in the room is heated as quickly as possible.

Air heating has no pronounced shortcomings.However, some features should be considered:

• Warm air is displaced upward, so it is desirable to place air ducts under the floor or in the lower part of the room, which is not always possible
• Air ducts have a larger sectional size than pipes, so the task of "hiding" them is not always easy to solve. Accordingly, the holes for them in the walls and ceilings are also much larger.

Maintaining a comfortable temperature in the house while spending a minimum amount of money is the dream of absolutely any homeowner. In this article, we will look at how to perform air heating. private house hands, how such a system works and what are its advantages. It will also highlight some nuances of self-assembly and operation of the air heating system. Let's get started!

Heating, ventilation and air conditioning in one installation

A system of this type includes either a water heater or a heat generator. These devices are responsible for heating the air. In the room, warm air is distributed using a special fan that directs it to the desired areas. by the most in the best way in the organization air space heating are portable heat guns. They quickly and intensively heat the necessary areas. Currently, many have begun to use this method in country houses and in the country.

Pros and cons of air heating in the house

The advantages of this heating method include:

• The efficiency is up to 93%;
• there are no intermediate links during the transfer of warm air, such as radiators and pipes;
• heating and air conditioning systems can be easily combined.Therefore, the temperature in the room is maintained exactly as it was set by the users;
• low passivity of the system, with which you can heat the necessary areas to a high temperature.

But, despite the many positive qualities of heating, there are also disadvantages. They must be remembered by those who want to make air heating of a private house with their own hands. These include:

• installation of the unit can only be carried out during the construction of the premises. It is imperative to develop and calculate all the parameters of the system before carrying out construction work;
• air heating must be constantly maintained;
• this system is not improved;
• electricity consumption is quite large. To save money, it is best to purchase a backup power supply.

Scheme and installation device

Below is the components of air heating of a private house with your own hands:

• Bake;
• Filter elements;
• A pipe that takes air from a room;
• Hood;
• A pipe that brings fresh air;
• Supply of warm air to the room;
• A system that removes cooled air from the house;
• Chimney.

In the form of a heat generator, a liquid or gas heater equipped with a programmable controller is perfect. After the house is completely warmed up, the automation immediately works and maintains the temperature according to the specified parameters.

Calculation of the heating system at home

The calculation of heating systems for a private house is the very first thing that begins with the design of such a system.We will talk with you about the air heating system - these are the systems that our company designs and installs both in private homes and in commercial buildings and industrial premises. Air heating has many advantages over traditional water heating systems – you can read more about it here.

System calculation - online calculator

Why is a preliminary calculation of heating in a private house necessary? This is required to select the correct power of the necessary heating equipment, which allows you to implement a heating system that provides heat in a balanced way to the corresponding rooms of a private house. A competent choice of equipment and the correct calculation of the power of the heating system of a private house will rationally compensate for heat loss from building envelopes and the flow of street air for ventilation needs. The formulas themselves for such a calculation are quite complex - therefore, we suggest you use the online calculation (above), or by filling out the questionnaire (below) - in this case, our chief engineer will calculate, and this service is completely free.

How to calculate the heating of a private house?

Where does such a calculation begin? Firstly, it is required to determine the maximum heat loss of the object (in our case, this is a private country house) under the worst weather conditions (such a calculation is carried out taking into account the coldest five-day period for this region). It will not work to calculate the heating system of a private house on the knee - for this they use specialized calculation formulas and programs that allow you to build a calculation based on the initial data on the construction of the house (walls, windows, roofs, etc.).As a result of the data obtained, equipment is selected whose net power must be greater than or equal to the calculated value. During the calculation of the heating system, the desired model of the duct air heater is selected (usually it is a gas air heater, although we can use other types of heaters - water, electric). Then the maximum air performance of the heater is calculated - in other words, how much air is pumped by the fan of this equipment per unit of time. It should be remembered that the performance of the equipment differs depending on the intended mode of use: for example, when air conditioning, the performance is greater than when heating. Therefore, if in the future it is planned to use an air conditioner, then it is necessary to take the air flow in this mode as the initial value of the desired performance - if not, then only the value in the heating mode is sufficient.

At the next stage calculation of air heating systems of a private house comes down to the correct determination of the configuration of the air distribution system and the calculation of the cross sections of the air ducts. For our systems, we use flangeless rectangular air ducts with a rectangular section - they are easy to assemble, reliable and conveniently located in the space between the structural elements of the house. Since air heating is a low-pressure system, certain requirements must be taken into account when building it, for example, to minimize the number of turns of the air duct - both the main and the terminal branches leading to the grates. The static resistance of the route should not exceed 100 Pa.Based on the performance of the equipment and the configuration of the air distribution system, the required section of the main air duct is calculated. The number of terminal branches is determined based on the number of feed grates required for each specific room of the house. In the air heating system of a house, standard supply grates with a size of 250x100 mm are usually used with a fixed throughput - it is calculated taking into account the minimum air speed at the exit. Thanks to this speed, air movement is not felt in the premises of the house, there are no drafts and extraneous noise.

The final cost of heating a private house is calculated after the end of the design stage based on the specification with a list of installed equipment and elements of the air distribution system, as well as additional control and automation devices. To make an initial calculation of the cost of heating, you can use the questionnaire for calculating the cost of the heating system below:

online calculator

Installation Recommendations

The most important point when performing the installation is the order of operations. First of all, it is necessary to install an air heater with a heat exchange chamber. From it comes the wiring and mounting of the air heater. Thermal insulation of channels must be carried out without fail. Branches are made through flexible hoses. Sleeves, in turn, are mounted in the wall.

The heat source is the most important detail. In order to connect it, it is best to use the services of specialists. But if you want to do this work yourself, you should read and understand the instructions very carefully.It is recommended to install the structure in a separate room. A basement would be perfect. The chimney is desirable with a sandwich construction. The heat exchanger itself is connected to the air duct, and the fan is located under the combustion chamber.

Placement of the heat generator in a separate room

Mounting air heating systems - a complex and responsible process, which is preceded by painstaking calculation and selection of equipment. With proper theoretical preparation, it is quite possible to do the work with your own hands. In all other cases, contact a specialist.

Types of air heating

There are two fundamentally different schemes of this type of heating

Air heating combined with ventilation

The transfer of heated air is carried out using elements of supply and exhaust ventilation. In this case, the operating parameter is not only the temperature in the room, but also the set air exchange rate.

Heat is generated by boilers or gas heat generators. A duct system is connected to them, through which warm air is distributed for all areas of heated premises. The system can be supplemented with filtration, humidifier, recuperator.

Oil boilers

It is possible to heat a dwelling with the help of equipment that runs on liquid fuel. Solar oil is used as fuel. Such boilers are equipped with fan burners.

This device atomizes the fuel and delivers it to the combustion chamber.

The device is equipped with a special regulator. It controls the appliances that are connected to the boiler. it could be a burner or a pump.

An important parameter of a liquid fuel boiler is power. This option requires a preliminary calculation. This takes into account the number of window and door openings, the thickness of walls and ceilings.

For mounting boiler for liquid fuel is selected a separate room. It should have a hood and a place to store fuel.

To make heating houses without gas and electricity, it is necessary to equip the device with a special filter. This will prevent the injectors from getting dirty.

If the fuel needs to be replaced, the burner is reset.

Solar equipment is characterized by noiselessness and performance.

Liquid-fuel structures have high efficiency and can heat large rooms.

This system is completely autonomous, which allows heating without gas and wood. Permits are not required for the installation of such a system. Similar designs work for various types of fuel and with any coolants.

When arranging equipment, it is worth considering the following features:

1. Fuel costs increase compared to gas appliances.
2. A container for storing fuel raw materials is installed in the room.
3. A separate boiler room is being set up, as the heating system is characterized by unpleasant odors.
4. Electricity will be required, as a backup generator must be started when the power goes out. In this case, you can heat the house without gas.

If we compare performance and characteristics, a liquid fuel boiler is on the same level as a gas boiler, it differs only in the price of fuel and its types.

Service: main features

In order to minimize the number of breakdowns during the service life, it is necessary to provide the system with timely maintenance. The frequency of conducting depends on its complexity, intensity of use, and other factors.

Maintenance is best left to professionals.

Air heating of a country house requires the following regular actions:

• Visual inspection of equipment, diagnostics of individual units.
• Filter cleaning and replacement, humidifier pad cleaning and replacement, heat exchanger cleaning.
• Automation check.

Timely maintenance will help to avoid power loss, equipment breakdowns, repairs. Some work can be carried out independently, such as replacing and cleaning the filter or cleaning the heat exchanger. Other jobs require qualifications and it is better to leave them to specialized companies.

Video description

In this video we will discuss whether it is possible to install air heating yourself:

In order for the procedure to be successful and fast, it is recommended to order a regular check of the system in a trusted company. Many users enter into a service contract with one company, and specialists perform work every season or at other established intervals.

A properly designed and maintained system will last a long time

Video description

Air-to-air heating or air heating + its pros and cons in this video:

Conclusion

The creation of an air heating system is a profitable solution, since it is distinguished by practicality, a high level of comfort and economy.It is recommended to carry out the design at the construction stage of the building: this will help to take into account all the nuances of the layout, calculate the efficiency and prevent such errors as installing insufficient power equipment or uneven heating. Since installation requires special knowledge and experience, arrangement of air heating needs to be entrusted to experts.

DIY installation recommendations

For laying the main lines of natural circulation, it is better to use polypropylene or steel pipes. The reason is the large diameter, polyethylene Ø40 mm and more is too expensive. We make radiator eyeliners from any convenient material.

An example of installing a two-pipe wiring in a garage

How to make the wiring correctly and withstand all the slopes:

1. Start with markup. Designate the battery installation locations, connection points for connections and highway routes.
2. Mark the tracks on the walls with a pencil, starting from the distant batteries. Adjust the slope with a long building level.
3. Move from the extreme radiators to the boiler room. When you draw all the tracks, you will understand at what level to put the heat generator. The inlet pipe of the unit (for the cooled coolant) must be located at the same level or below the return line.
4. If the floor level of the firebox is too high, try moving all the heaters up. Horizontal pipelines will rise next. In extreme cases, make a recess under the boiler.

Laying a return line in a furnace with a parallel connection to two boilers

After marking, punch holes in the partitions, cut grooves for the hidden gasket. Then check the traces again, make adjustments and proceed with the installation.Follow the same order: first fix the batteries, then lay the pipes towards the furnace. Install expansion tank with drain pipe.

The gravity pipeline network is filled without problems, Mayevsky's cranes do not need to be touched. Just slowly pump water through the make-up tap at the lowest point, all the air will go into the open tank. If any radiator remains cold after warming up, use the manual air vent.