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Radiator Selection from Room Load
Size a radiator from the room heat load: the EN 442 ΔT correction gives the required nominal (ΔT50) catalogue output, with a heat-pump oversizing advisory.
The Ensign ToolboxRadiator Selection from Room LoadSize a radiator from the room heat load: the EN 442 ΔT correction gives the required nominal (ΔT50) catalogue output, with a heat-pump oversizing advisory.
Room load
W
The room's design heat loss — enter it, or take it from Room-by-Room Heat Loss
EN 442 characteristic exponent — panel radiator ≈ 1.3 (1.2–1.35)
System temperatures
°C
Boiler system ≈ 75 °C; heat pump ≈ 35–50 °C
°C
°C
ΔT = (flow + return) / 2 − room; catalogue ratings assume ΔT 50 K
Enter the room heat load and system temperatures to size the radiator