Closed heating system (definition)

Closed heating system - is a system in which coolant (water or other working agent) circulates in a sealed circuit without direct contact with the atmosphere. In such a system, water is heated in a boiler or other heat generator and then moves through pipes through radiators, heated floors or other heating devices, giving off heat to the premises. After this, the coolant returns back to the heat generator for reheating.

Closed heating system: features

1. Tightness: A closed heating system is characterized by complete isolation of the coolant from the external environment with no contact with air. This reduces the risk of corrosion in pipelines and radiators and minimizes water evaporation.
2. Pressure: A closed heating system requires pressure regulation, which is controlled by an expansion tank and a pressure reducer. The expansion tank compensates for changes in the volume of the coolant during heating and cooling, preventing excess pressure and leaks.
3. Safety: Due to the tightness and pressure control, closed systems are safer and more resistant to temperature changes. They can also use antifreeze or other specialized heat carriers that do not evaporate or lose their properties at high temperatures.

Advantages:

• No need to add water: Since the system is sealed, the coolant does not evaporate and its level remains stable, which eliminates the need for regular water top-up.
• Efficiency: A closed system allows for better control of temperature and pressure, which increases the efficiency of heat supply. Also, due to the absence of contact with air, the risk of corrosion is reduced, which extends the service life of the equipment.
• Economical: Closed systems can be more economical to operate because the coolant circulates with minimal heat loss.

Installation of a closed system:

1. Expansion tank: A membrane expansion tank is installed, which compensates for the expansion of water during heating. It is usually placed in the boiler room or on the return circuit of the system.
2. Circulation pump: A closed system requires the installation of a circulation pump to ensure the movement of the coolant along the circuit, since natural circulation may be insufficient due to the lack of contact with the atmosphere.
3. Shut-off valves: Check valves, safety valves and other elements are installed in the system to maintain the required pressure and prevent backflow of water.
4. Air vents: Automatic air vents are installed to remove air from the system, which prevents the formation of air locks and ensures stable operation of the system.

Important! A closed heating system depends on the availability of electricity to power the equipment; when deploying it, alternative power supply devices must be installed.

Difference from an open system:

1. Contact with the atmosphere: In an open heating system, water circulates in an open circuit that is in contact with the atmosphere, which leads to evaporation of the coolant and the need for regular topping up.
2. Open expansion tank: Open systems use an open expansion tank, which is installed at the highest point of the system. This allows for changes in water volume, but increases the risk of air entering the system, which can lead to corrosion.
3. Less tightness: Open systems are less airtight, which can lead to an increased risk of leaks and reduced heating efficiency.
4. Differences in editing: Installing a closed system requires the installation of additional equipment such as circulation pumps and membrane expansion tanks, making it more complex and expensive than an open system. However, a closed system is more efficient and durable, making it the preferred choice for modern heating systems.