Radiator Correction Factor Tool

Calculate radiator output at different delta T values for heat pump systems and conventional heating.

Emitter Output at Delta T

Emitter Output (BTU / KW) 1000

Select Delta T (°C / K)

Emitter Output (at Delta T)

1000.00

BTU / KW

This calculator will tell you what output you will end up with if you reduce the delta T to the selected from the dropdown.

Required Radiator Output at Delta 50°C

Heatloss (BTU / KW required) 1000

Select Delta T (°C / K)

Output of Emitter at Delta 50°C needed

1000.00

BTU / KW

This calculator is used to work out which standard radiators at 50 degrees delta to meet the needs of heat pumps.

Delta T Conversion Factor Table

Delta T (°C / K)	Conversion Factor
5	0.05
10	0.123
15	0.209
17.50	0.257
20	0.304
25	0.406
30	0.515
35	0.629
40	0.748
45	0.872
50	1.000
55	1.132
60	1.267
65	1.406
70	1.694

Important: These calculations are based on radiator performance curves. Always consult manufacturer data sheets for specific radiator models and verify calculations with a qualified heating engineer.