Sisäkierto

Sisäkierto is a term used in Finnish engineering to describe the circulation of a liquid within a closed piping network. The concept refers to moving heat-bearing fluid, typically water or a water-glycol mixture, through a loop that connects a heat source, piping, and heat emitters such as radiators, underfloor heating, or industrial equipment. The circulation is driven by a pump and is designed to maintain a continuous, controlled flow within the system.

Typical components of a sisäkierto system include a heat source (boiler, heat pump, or solar collector), circulation pump, piping network, heat emitters, an expansion vessel, and various valves and sensors for regulation. Systems may be designed as single- or two-pipe configurations and can include bypasses to control flow and temperature. The main aim is to transfer energy efficiently from the heat source to the places where heat is needed, while maintaining safe pressure and preventing overheating or freezing.

Advantages of sisäkierto include uniform heat distribution, improved energy efficiency through controlled flow, and the ability to integrate multiple heat sources (for example, boiler and solar). Proper design and balancing of the loop are important to prevent temperature stratification, excessive pump energy use, or inadequate heat delivery.

Maintenance considerations involve ensuring leak-free connections, removing air from the circuit, monitoring pressure, and dosing corrosion or inhibitor treatments as recommended. Regular inspection of pumps, expansion vessels, and sensors helps sustain reliable operation and extend system life.