Heating/ CALCULATOR
Hydronic heating flow rate
Convert a heating load and design supply-return temperature difference into a water-flow estimate.
Use the heat that the water circuit must carry at the selected condition.
Use the circuit supply temperature, not the heat-source nameplate maximum.
Use the intended return temperature at the same design condition.
Use only circuits intended to operate together; equal flow is a simplifying assumption.
Supply-return temperature difference
10.0 °C
Required total water flow
14.3 L/min
Required total water flow
860 L/h
Average flow per equal circuit
2.9 L/min
Interpretation:At the entered temperature difference, the system needs about 14.33 L/min in total and 2.87 L/min per equal active circuit. Pump head and balancing still require a hydraulic design.
Water at approximately 1 kg/L with specific heat 4.186 kJ/(kg·K), steady heat transfer and equal circuit flow. Glycol, changing water properties, emitter output, control behaviour, pipe loss, valve authority, hydraulic resistance, pump head and balancing are excluded. Use a qualified hydronic design for equipment selection.