Input Parameters
About This Calculator
- Automatically corrects heat output based on actual temperature difference
- Exponent n = 1.30 (column cast iron) / 1.33 (panel)
- Recommended sections are rounded up to the nearest whole number
- This calculator provides an early-stage sizing estimate. Verify final selection against manufacturer data.
How this radiator sizing calculator works
The calculator corrects nominal radiator output for the actual mean water-to-room temperature difference. Column radiator results are reported as section counts, while panel radiator results are area-based.
Inputs explained
- Heat load is the room heating demand that the radiator must cover.
- Radiator type selects nominal output and heat-output exponent assumptions.
- Supply and return water temperatures determine mean water temperature.
- Room temperature determines the actual radiator temperature difference.
- The selected standard changes the reference temperature difference and nominal output values.
FAQ
Why are recommended sections rounded up?
Radiators are selected in whole sections, so the theoretical requirement is rounded up to avoid undersizing.
Why do lower water temperatures need more radiator area?
Lower mean water temperature reduces heat output per section, so more sections or larger area are required.
Can I compare panel and column radiators directly?
Treat panel output as area-based and column output as section-based. Always verify with manufacturer catalog data.