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 autonomous devices. This is due primarily to two main advantages of these systems over centralized ones. Firstly, the installation of autonomous equipment provides transparency in the payment of utilities. Secondly, houses equipped with such systems do not depend on planned long-term shutdowns of hot water supply in the summer months. A large number of different types of equipment and components are presented on the market.
The choice
The main criteria for selecting the optimal heating system is the relationship of indicators such as price and quality. With a thoughtful approach to the selection, installation and proper functioning, you can get an uninterrupted supply of housing with hot water and heat at any time of the year at minimum cost. In this case, the durability and reliability of the heating system also increases. Properly installed and functioning equipment helps to solve one of the most important tasks, 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 in an autonomous mode, without the need for constant monitoring by a person.
Design phase
A modern low-rise house (cottage) implies the presence of a heating system and hot water supply. However, during the construction of almost every structure, many problems arise associated with the installation and commissioning of equipment. Installation of heating systems in each building begins at the time of designing the building. The architect's tasks include planning the optimal installation of equipment with determining the location of all elements. What does the heating system of a private house consist of? The scheme includes three parts:
1. The boiler. He is responsible for heat generation.
2. Wiring diagrams of heating systems. These are, in particular, connecting pipes through which heat is transferred.
3. The heating system itself. Most often these are radiators. Less commonly used is a heating system of a fundamentally different type, based on floor heating (underfloor heating).
Important points
The boiler power, which ensures the most efficient operation, is determined by a certain ratio when designing a cottage for domestic needs. It looks like this: per 10 m2 of area should be 1 kW. Moreover, already at the design stage they are determined with the final boiler capacity. This, in turn, allows you to immediately select its brand and model. However, it is worth noting that the total footage of the constructed building is not the only criterion for choosing equipment. Correct 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 of walls, floors, ceilings;
- the size and number of windows, their type and properties, etc.
The combination of all factors, taking into account the capabilities of the installation, allows you to choose the optimal mode of hot water supply and heat supply in each specific structure. 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 species are also widely used. In particular, one- or two-pipe (beam) systems are popular.
Basic concepts used when installing stand-alone equipment
For a clearer understanding of the differences between the schemes, it is necessary to define several key terms used by specialists.
Water heating device - a device with which heat is extracted from the system for further transmission to the room. The most commonly used are various types of radiators and batteries, recuperators, fan coil units and underfloor heating. In everyday life, as a rule, all devices are simply called - "battery".
The heat carrier is the fluid 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 a lower freezing point. This prevents freezing of the liquid circulating in the heating system in the cold season.
The general heating circuit is a closed system through which the coolant circulates. In the process of its movement, as was noted above, the liquid is repeatedly heated by the boiler and gives off the received heat 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 travel (current) is a specific part of the overall circuit. On it there is a movement of heat-received liquid to water heating devices . Reverse (current) is part of the overall circuit structure. It originates from water heating appliances to the place of heating (boiler).
Scheme of the heating system. Classification
Depending on the way the coolant circulates, the circuit of the home heating system can be forced and natural. The latter (in some sources gravity or gravity) acts due to the movement of the coolant due to the physical properties of the fluid. In this case, we mean the change in the density of water with increasing temperature. This scheme of the heating system assumes that the coolant heated with the help of the boiler has a lower density than cold. As a result of this, the process of displacement by a liquid with a lower temperature brought back by the warmer in direct current. In this case, the hot fluid rises up the riser and spreads along the heating circuit. To ensure better fluid movement, 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 in the case of a total heating circuit length of more than 30 m. This is due to the fact that with a meter of more than 30, the coolant has time to cool before a full circle passes. As a result, the general circulation is disturbed. The heating system diagram, based on forced movement (pumping), works due to a special element - the pump. It provides a differential pressure in forward and reverse strokes. The properties of this system depend only on the characteristics of the pump, which is used for its operation. The disadvantage in this case is the dependence of the unit operating on the power supply.
Connection Classification
Installation of heating systems can be carried out in two ways. The following types are distinguished, depending on the method of connecting devices with a heat source:
1. One-pipe. It is based on a serial connection.
2. Two-pipe (beam or collector). It is based on parallel connection.
Serial connection
Heated coolant circulating through a single-pipe heating system, in turn enters all heating devices. In this case, each element is given part of the thermal energy. This scheme is the simplest among all. Its implementation is the least expensive compared to the rest. However, it should be said about the disadvantages that a single-pipe heating system has :
- the circuit makes it impossible to separately regulate the level of heat transfer for each heating device;
- as you move away from the source, a decrease in the amount of thermal energy is observed.
Parallel connection
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 course is carried out. The second pipe (lower) is the reverse current. With this connection, it is possible to control the level of heat transfer for each battery. This happens by regulating 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 heating system circuit is one of the types of parallel connection. A significant difference should be considered the convergence of the extended elements of the forward and reverse motion on special combs located in the immediate vicinity of the heater. The advantage of this scheme is the lack of various compounds. The disadvantage of the connection is the high length of the pipes used. Before commissioning, this connection must be balanced, that is, adjust the flow and flow rate of the coolant in each loop. Only in this case a uniform heat distribution is achieved across the batteries.
General installation recommendations
1. Use a pump to increase heat to the farthest radiators. 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 source of its power (battery).
3. The best heat-insulating properties are possessed by plastic and metal-plastic pipes. When using metal elements during the transfer of the coolant from the source to the battery, more energy is lost.
4. The forced circulation circuit allows reducing the volume of coolant in the system by reducing the diameter of the pipes to be connected and using batteries with a smaller internal volume. In this case, not so much fuel is spent on the general heating of the system, while the heat transfer increases.