Through a district heating network, the heat-producing plant pumps heated supply water to consumers where it is used as room floor heating and to generate domestic hot water. The domestic hot water gets heated in a heat exchanger in which the heated supply water transfers its heat to the water coming out of the taps.

For room heating, the supply water might be used directly. Alternatively, a heat exchanger could also transfer the heat to an internal circulation. The supply water which is now cold because the heat has been transferred to domestic hot water and room heating then returns to the district heating plant. The district heating supply water circulates endlessly in a closed pipeline.

Ayvaz produces special metal expansion joints with high compression capacity with outer cover. Pipelines of the district heating systems are often buried under ground. Outer covers help expansion joints to be insulated and protects bellows.