What is VWART?
VWART stands for Volume Weighted Average Return Temperature. The temperature calculated is that being circulated back to the network from the Heat Interface Unit (HIU). In the latest BESA Test Regime, the VWART is calculated across both heating and hot water modes over an annual usage period. This measure providing a reasonable estimate for the impact of the tested HIU on the performance of the heat network. Generally, the lower the return temperature back to the central plant, the more efficiently the network can operate.