The temperature difference between supply and return, known as ΔT, is a key diagnostic element for the hydraulic circuit operation.
Large ΔT
It may indicate insufficient water flow, closed valves, a clogged filter, or a restriction in the network.
Very small ΔT
It may indicate excessive flow or low heat absorption by the terminals.
No single value for everything
The correct ΔT depends on the design study, the manufacturer, and the type of terminals.
Practical use
Simultaneous measurement of supply, return, and flow rate provides a more reliable picture of actual operation.
