In the process of designing low-rise private houses, it is necessary to solve one of the main tasks - the issue of heating. Recently, more and more people prefer standalone devices. This is primarily due to the two main advantages of these systems over centralized ones. Firstly, the installation of stand-alone equipment provides transparency in utility bills. Secondly, houses equipped with such systems do not depend on planned long-term shutdowns of hot water supply during the summer months. There are a large number of different types of equipment and components on the market.
The main criteria for choosing the optimal heating system is the relationship between such indicators as price and quality. With a thoughtful approach to selection, installation and ensuring proper functioning, you can get an uninterrupted supply of hot water and heat to your home at any time of the year at minimal cost. In this case, it also increasesdurability and reliability of the heating system. Properly installed and functioning equipment helps to solve one of the most important tasks that are unattainable, for example, with stove heating - maintaining a certain temperature over a long period of time. At the same time, the system itself can work offline, without the need for constant human control.
Modern low-rise house (cottage) implies a heating system and hot water. However, during the construction of almost every structure, there are many problems associated with the installation and start-up of equipment. Installation of heating systems in each building begins at the time of designing the building. The task of the architect is to plan the optimal installation of equipment with the determination of the location of all elements. What does the heating system of a private house consist of? The scheme includes three parts:
1. Boiler. He is responsible for generating heat.
2. Wiring diagrams for heating systems. These are, in particular, connecting pipes through which heat is transferred.
3. The heating system itself. Most often these are radiators. Rarely used is a heating system of a fundamentally different type, based on underfloor heating (underfloor heating).
The power of the boiler, which provides the most efficient operation, is determined by a certain ratio when designing a cottage for domestic needs. It looks like this: for 10 m2 of areashould account for 1 kW. At the same time, already at the design stage, they are determined with the final power of the boiler. This, in turn, allows you to immediately select its make and model. However, it is worth noting that the total footage of the constructed building is not the only criterion for choosing equipment. Proper professional selection should be carried out taking into account a number of key factors. These include, in particular:
- the material from which the house is made;
- the thickness of the walls of the structure;
- number of floors;
- material used as insulation for walls, floors, ceilings;
- size and number of windows, their appearance and properties, etc.
The combination of all factors, taking into account the possibilities of installation, allows you to choose the optimal mode of hot water supply and heat supply in each specific building. Currently, one of the most popular and practical is the heating system of a private house, the scheme of which is based on the use of forced and natural circulation of the coolant. Other types are also widely used. In particular, one- or two-pipe (beam) systems are popular.
Basic concepts used when installing stand-alone equipment
To better understand the difference between the schemes, it is necessary to define several key terms used by specialists.
A water heating device is a device with which heat is extracted from the system for further transfer to the room. Most oftenvarious types of radiators and batteries, recuperators, fan coil units and heated floors are used. In everyday life, as a rule, all devices are simply called “battery”.
Heat carrier is a liquid that is heated by the boiler. It transfers heat to the room through various types of batteries. The most common coolants are water and antifreeze. The latter consists of ethylene glycol and H2O. The main difference between antifreeze and water is the lower freezing point. This prevents the liquid circulating in the heating system from freezing during the cold season.
The common heating circuit is a closed system through which the coolant circulates. In the process of its movement, as noted above, the liquid is repeatedly heated by the boiler and gives off the heat received with the help of batteries. The heating circuit, in addition to the main elements (boiler, radiators, connecting pipes), includes a number of additional equipment. Its elements include: pumps, pressure sensors, valves, expansion tanks and others.
Forward stroke (current) - a certain part of the overall circuit. Through it, the movement of the heat-receiving liquid to the water heating devices occurs. Reverse stroke (current) is part of the overall structure of the circuit. It originates from water heating devices to the place of heating (boiler).
Scheme of the heating system. Classification
Depending on the way the coolant circulates, the scheme of the home heating system can be forced and natural. The latter (in somegravity or gravitational sources) acts due to the movement of the coolant due to the physical properties of the liquid. In this case, we mean the change in the density of water with an increase in its temperature. This scheme of the heating system assumes that the coolant heated by the boiler has a whiter low density than the cold one. As a result, the process of displacement by a liquid with a lower temperature, brought by the reverse stroke, warmer into the direct current, takes place. In this case, the hot coolant rises up the riser and spreads along the heating circuit. To ensure better fluid movement, the equipment elements are located at a slight slope. Such a home heating scheme is easy to implement. Its advantage can be considered a small dependence on other communications. However, the use of such a scheme is very limited. It becomes ineffective when the length of the common heating circuit is more than 30 m. This is due to the fact that with a footage of more than 30, the coolant has time to cool before it goes full circle. As a result, the general circulation is disturbed. The scheme of the heating system, based on forced movement (pumping), works due to a special element - a pump. It provides a pressure difference in the forward and reverse strokes. The properties of this system depend only on the characteristics of the pump that is used for its operation. The disadvantage in this case is the dependence of the unit that ensures the operation of the power supply.
Installationheating systems can be carried out in two ways. There are the following types, depending on the method of connecting devices with a heat source:
1. Single pipe. It is based on serial connection.
2. Two-pipe (beam or collector). It is based on a parallel connection.
Heated coolant circulating through a single-pipe heating system is supplied in turn to all heating devices. At the same time, a part of thermal energy is given to each element. This scheme is the simplest among all. Its implementation is the least expensive compared to the others. However, it should be said about the shortcomings that a single-pipe heating system has:
- the scheme does not make it possible to separately regulate the level of heat transfer for each heating device;
- as you move away from the source, there is a decrease in the amount of thermal energy.
The scheme of a two-pipe heating system involves the use of a supply of 2 connections to each battery. On one of them (upper) a direct move is carried out. On the second pipe (lower) - reverse current. With this connection, it is possible to control the level of heat transfer for each battery. This happens through the regulation of the coolant passing through it. A significant drawback of this scheme is the installation of additional elements of the heating system (pipes, valves, sensors, etc.). This significantly affects the final cost of the entire installation.
Beam (collector) connection
This scheme of the heating system is one of the varieties of parallel connection. A significant difference should be considered the convergence of the stretched elements of the forward and reverse strokes on special combs located in the immediate vicinity of the heater. The advantage of this scheme is the absence of various connections. The disadvantage of the connection is the high length of the pipes used. Before commissioning, this connection must be balanced, that is, the supply and flow of coolant in each loop must be adjusted. Only in this case is achieved a uniform distribution of heat over the batteries.
General recommendations for installation
1. To increase the heat supply to the farthest radiators, a pump should be used. This is true even with connections for natural circulation.
2. It should be remembered that the diameter of the pipes directly depends on the use of the pump in the system. The more powerful the unit, the smaller the cross section. When using the pump, it is allowed not to use slopes. However, when installing the unit, it is recommended to have an independent backup power source (battery).
3. Plastic and metal-plastic pipes have the best thermal insulation properties. When using metal elements, more energy is lost in the process of transferring the coolant from the source to the battery.
4. The forced circulation circuit allows you to reduce the volume of coolant in the system forby reducing the diameter of the connected pipes and using batteries with a smaller internal volume. In this case, not so much fuel is spent on the overall heating of the system, while heat transfer increases.