Apartment buildings are connected to the central heating network, and private sector buildings are connected to the autonomous one. In both cases, the quality of heating is affected by the life of the house, the condition of the equipment and communications. It is also important dependent or independent heating system, which differ in the type of wiring diagram.
Scheme of dependent heat supply
The dependent heat supply scheme provides for the communication of the heat network and internal communications in the house through the main pipes. Water from the heat distributor is supplied to the objects, that is, it moves from the central boiler room to the apartment.
A feature of the circuit is its dependence on the temperature of the coolant. If it reaches up to 95 degrees, water immediately enters the heating pipes. When the temperature rises to 105 degrees, a mixing unit is needed - an elevator. It mixes cold water from radiators into hot water located in the main.
The advantages of a dependent heating circuit include the reliability of the equipment and the absence of the need for its control. Installation work and the cost of materials are inexpensive, since additional hot water pipes are not laid - hot water is taken directly from the heating main.
Connection according to the dependent scheme is realized through direct connection to the line, with the help of an elevator, pumps on a jumper, a return and supply network, or in a mixed way. In the latter case, an elevator and a pump are installed.
With a dependent connection, mineral and mechanical impurities often remain in the water, shortening the wiring life.
Independent heat supply scheme
An independent heating circuit consists of a primary and secondary circulation circuits separated by a heat exchanger. The coolant is sent from the CHP or boiler room to the central heat point. Then it moves to the heat exchanger (main circuit), and then goes to heat the house (auxiliary circuit). Both circuits are isolated, water does not mix.
In an independent highway, the coolant moves forcibly - due to the circulation pump. Water flows through heating devices constantly. In case of leaks there is an expansion tank.
Advantages and disadvantages of connecting
Dependent circuit
Water is supplied and received for heating and water supply from the heat route, which leads to a number of advantages:
- simplicity of design and low cost of subscriber devices;
- the ability of the system to withstand temperature fluctuations;
- smaller diameter of reinforcement;
- profitability of the coolant flow;
- low operating costs.
Negative factors in the use of a dependent heating system include:
- The formation of dirt, rust and scale in the lines. They enter aluminum and bimetallic devices and cause pipe rupture.
- Frequent pressure fluctuations, water hammer due to reduced water intake. Phenomena can lead to rupture of polymer reinforcement.
- Low quality of the coolant, despite cleaning and desalination in the boiler room.
- The difficulty of adjusting the temperature even with full bore valves.
To remove blockages, an additional sump is mounted on the mixer.
Independent scheme
In the presence of a closed circuit, water from a plate heat exchanger can be supplied to any wiring. The dependent heat supply scheme has several advantages:
- the temperature of the coolant in the pipes is controlled by the user;
- good energy saving indicators;
- compatibility with any heat carrier;
- lack of impurities in the hot water supply line;
- the ability to purify and filter water in the circuits;
- no risk of pressure surges and water hammer.
The disadvantages of independent connection include:
- complicated service;
- the impossibility of self-repair;
- high financial costs for the organization.
An independent type highway saves water consumption by 10-40%.
Dependence of systems on electricity
The energy dependence of systems is defined as the ability to work in the presence or absence of electricity. Non-volatile communications are mounted in conditions of prolonged blackout. For the normal functioning of heating, several methods are used:
- Installation of an electric generator or inverter battery. Devices start the power after the network is de-energized.
- Providing non-volatile heat generation. You will need an automatic boiler - pellet, oil or gas. The equipment works without electricity, but uses the main fuel uneconomically.
- Creation of gravitational pressure. The fluid moves through the difference in densities during heating and cooling. The heated water masses go up, the cooled down go down. Gravity pressure is created by installing the boiler at a lower point, sloping the horizontal pipe along the movement of water.
For gravity heating, pipes with a diameter of 35 to 50 mm are needed.
When implementing a circulation or volatile heat supply, a circulation pump is needed. The system is connected to pipes of any diameter, special convectors and warm floors also work for heating. The water temperature is maintained at a given level. In case of a lack of electricity, generators are installed.
Which system is justified in a private house
An independent gravity system is used for production workshops, houses above 12 floors - it ensures the quality of heating due to the uniform distribution of heat. The costs of equipment and installation activities pay off if there is a large area. Calculations and selection of the scheme are done by specialists. They recommend installing several heat exchangers to heat the primary, secondary coolant and the domestic hot water line.
In the conditions of villages, summer residences, small enterprises, technological features of heat supply are taken into account. There is practically no central heating in such places - an individual is often used, with a separate boiler room. It needs to be equipped taking into account non-volatility. For this purpose, boilers are used:
- Pellet. Special homogeneous granules are laid in them - pellets from pressed chips or husks. The owner loads fuel for several days, electricity is used only to power the screw motor.
- Pyrolysis. They work on the principle of afterburning gases in the secondary chamber. They work on electricity from generators. Air is supplied by special valves.
- With top burning. Fuel is laid down and set on fire.
- With forced air supply. Pellets or firewood are placed in a large single-chamber fire chamber. The fan and the damper blocking air access are located in the cellar.
The best option for a private house is a boiler, but for it you will need 20% more fuel compared to central heating.
Is it possible to make an independent system out of a dependent system
Using several technological methods, the dependent scheme can be converted into an independent system with the implementation of heat supply using:
- Hopper and conveyor belt for solid fuel boiler. When fuel materials burn out, new portions enter the firebox on the conveyor belt. It is powered from the mains.
- Pyrolysis boiler. Combustion takes two stages. On the first, firewood is pyrolyzed with a minimum supply of oxygen, on the second, residual gas is burned. An electric fan is used to create traction.
- Top burning equipment. Due to decay of the upper layer, the device works for 5 days on one tab of fuel. Air masses are pumped by an electric fan.
The best option for non-volatility is a gas boiler with manual ignition and an adjusting thermostat for flame.
In a dependent scheme, water enters the system through an elevator and mixes with the return masses. An independent system eliminates this process - heating occurs through a heat exchanger. Heat supply can work in conjunction with electricity or autonomously. It is necessary to select the connection method according to the heating area and the type of object.
