Among many heating schemes, a system with forced circulation of the coolant is distinguished by its versatility and wide functional capabilities. It can be used in the heat supply of a small private cottage or apartment, as well as in a large multi-storey building. Is it difficult to do it yourself, without the involvement of specialists? We will find out what the heating of a house with forced do-it-yourself circulation is, the schemes and the optimal equipment for a particular system.
Features of forced circulation heating
Modern forced-circulation water heating has replaced the gravity circuit. In the second, the movement of the coolant is due to the thermal expansion of the water when it is heated. This principle significantly reduced the efficiency of heat supply.
One of the determining factors in the feasibility of installing a water heating system with forced circulation is the relatively fast movement of the coolant along the highway. Due to this, a uniform distribution of heat occurs across all radiators in the circuit.
In addition, it should be noted such features of heating by pumping groups:
- The ability to install pipes of a small section: 20, 25 mm. This reduces the total volume of warm water in the system, which affects the consumption of energy;
- The choice of several piping installation schemesat. The forced heating system of a private house can be single-pipe, two-pipe or collector;
- Temperature adjustment both for individual elements, and in the whole system as a whole. Best of all, collector heating manages this task;
- Increased operating comfort.
However, along with this, it should be noted the disadvantages that a two-pipe or one-pipe heating system with forced circulation has. First of all, this is the installation of a pump group to increase the flow rate of the coolant. This entails an increase in primary costs, and also makes the operation of the entire system dependent on the supply of electricity. But these disadvantages are offset by the above advantages.
You can upgrade existing gravity heating. To do this, just install the pump. However, first you need to calculate the parameters of the system - large pipes are not always suitable for circuits with forced circulation.
Types of heating circuits with forced circulation
The main principle of operation of a forced circulation heating system is to install pumps to increase the flow rate of the coolant. The place of their installation directly depends on the selected piping layout.
In addition, the heating system of a private house with forced circulation should include security groups. This is necessary for timely stabilization of pressure in the pipes due to possible overheating of the coolant. Each type of heating with forced circulation has a number of features that directly affect the choice in a particular case. But regardless of this, a self-forced circulation heating system in addition to the pump should include the following components:
- Security group: air vent and bleed valve. Installed immediately after the boiler;
- Expansion tank. It is best to choose a membrane type design with the ability to replace an elastic valve;
- In the binding of each radiator should be balancing valve, Mayevsky crane. It is advisable to install a thermostat;
- Stop valves. It is necessary for partial or complete blocking of the flow of coolant in a particular section of the system.
Each of the above components must have operational characteristics that meet the parameters of a particular heating system. Otherwise, they will not fulfill the functions assigned to them.
The selection of certain components of the system is carried out according to a pre-made scheme for heating a house with forced circulation. The calculation should be as accurate as possible - using specialized programs or performed by professionals.
Single pipe system
This is an outdated scheme, which is practically not used for individual heating of a house. In a forced-circulation single-pipe heating system, there is only one supply line, in which radiators and batteries are connected in series.
The only advantage of this scheme is the small footage of the pipelines. However, in addition to this, the single-tube system has several significant drawbacks:
- Uneven distribution of coolant. The farther the radiator is located from the boiler, the lower the degree of heating of the hot water entering it;
- To carry out repair work, it is necessary to stop the heating boiler and wait until the coolant temperature drops to a normal level.
The pump power for single-pipe heating with forced circulation will be much less than for two-pipe. This is due to the lower volume of coolant in the system. Also, for laying pipelines less space is needed - they can be installed under the floor, skirting boards.
For a single pipe heating system with forced circulation, it is necessary to provide for the installation of a bypass for each radiator. This will make it possible to turn off the device without completely stopping the heat supply to the house.
Double pipe system
The scheme of a two-pipe heating system with forced circulation differs from a single-pipe heating system by the presence of another pipe for a cooled coolant. It runs parallel to the main one and chilled water from the radiators enters it.
During the design of the system, it is necessary to correctly draw up the layout of pipelines. The direct and return lines should be installed in close proximity to each other, but not more than 15 cm, in addition, the system can be with the same direction of movement of the coolant, with different vectors, and also a dead end. Most often, a one-way scheme is selected.
Forced-circulation water heating has several important features:
- The small diameter of the pipes is from 15 to 24 mm. This will be enough to create the required pressure indicators;
- Possibility to install both horizontal and vertical piping;
- A large number of rotary elements will affect the hydrodynamic performance of the system for the worse. Therefore, they need to be done as little as possible;
- When choosing flush mounting, inspection hatches are installed at the pipe joints.
In each forced heating system of a private house, it is necessary to provide a bypass channel in the circulation pump assembly. It is designed for gravitational motion of the coolant in the event of a power outage.
The operation of pumping equipment should ensure normal circulation in the system. To do this, you should correctly calculate its power and performance.
If the forced-circulation water heating system is equipped with polymer pipelines, they must be with a reinforced layer of aluminum foil or polyester.
Collector system
If the area of the house exceeds 150 m² or it has 2 or more floors - it is recommended to make a collector heating system with forced circulation by yourself. It is one of the modifications of the two-pipe scheme and is designed to increase the efficiency of heat supply.
The main element of the collector heating circuit is the distributor. It is a pipe with a round or rectangular cross-section, on which several pipes are installed. They are necessary for the distribution of coolant in individual heat supply circuits of the house.
A distinctive principle of the operation of a heating system with forced circulation of the collector type is the arrangement of pipelines independent of each other. This makes it possible to regulate the heat transfer of each of them, and also stabilizes the pressure in the system.
A circulation pump is installed on each nozzle of the collector to ensure the proper speed of the coolant. Such a heating system of a private house with forced circulation has a number of important features:
- An increase in the number of pipes and fittings. Each circuit is a separate heating system connected via a collector to a single network;
- To adjust the volume of the coolant, special elements are needed - temperature regulators and servos with temperature sensors;
- For the most efficient operation of the system, the installation of a mixing unit is recommended. It connects the direct and return pipes and mixes the flow of water to achieve the optimum temperature of the coolant.
The collector heating circuit of a house with forced circulation can consist of several distribution nodes. It all depends on the total area of the house, as well as the location of the premises in it.
The sum of the diameters of the nozzles on the collector should not exceed its cross section. Otherwise, there will be a destabilization of pressure in the system.
Design of heating with forced circulation
The primary task for self-installation of water heating with a circulation pump is to draw up the correct scheme. To do this, you need a house plan, on which the arrangement of pipes, radiators, valves and safety groups is applied.
System calculation
At the stage of drawing up the diagrams, it is necessary to correctly calculate the pump parameters for the forced heating system of a private house. To do this, you can use special programs or do the calculations yourself. There are a number of simple formulas that will help you make the calculation:
Pn = (p * Q * H) / 367 * efficiency
Where PH - rated power of the pump, kW,R - heat carrier density, for water this indicator is 0.998 g / cm³,Q - coolant flow rate, l,N - required pressure, m.
To calculate the pressure indicator in a forced home heating system, it is necessary to know the total resistance of the pipeline and the heat supply as a whole. Alas, it is almost impossible to do it yourself. To do this, use special software systems.
After calculating the resistance of the pipeline in the water heating system with circulation, you can calculate the required pressure indicator by the following formula:
H = R * L * ZF / 10000
Where N - calculated head, m,R - pipeline resistanceL - the length of the largest straight section of the highway, m,Zf - coefficient, which is usually equal to 2.2.
Based on the results, the optimal model of the circulation pump is selected.
If the calculated power indicators of the pump in the heating system with forced circulation, installed independently, are large, it is recommended to purchase paired models.
Installation of heating with circulation
On the basis of the calculated data, pipes of the desired diameter are selected, and to them - stop valves. However, the diagram does not show how the line is mounted. Pipelines can be installed in a hidden or open way. The first is recommended to be used only with full confidence in the reliability of the entire heating system of a private cottage with forced circulation.
It must be remembered that the quality of the system components will depend on its performance and performance. This is especially true for pipe and stop valves. In addition, for a two-pipe circuit of a heating system with forced circulation, it is recommended to follow the advice of professionals:
- Installation of an emergency power supply source for the circulation pump in the event of a power outage;
- When using antifreeze as a coolant, check its compatibility with materials for the manufacture of pipes, radiators and a boiler;
- According to the heating scheme of a house with forced circulation, the boiler should be located at the lowest point in the system;
- In addition to the power of the pump, it is necessary to calculate the expansion tank.
The technology of the circulation heating installation is no different from the standard. It is important to take into account the features of the contour house - the material of the manufacture of walls, its heat loss. The latter directly affects the power of the entire system.
Analytics of the parameters of heating systems with forced circulation will help to make an objective opinion about it:
