QUESTION: After using the “Easy heat guide for your room” on the home page of www.aelheating.com i now know the heat required for my room so how do i check that the radiator i have chosen will provide enough heat output. ANSWER: There is a simple calculation to check if the radiator you have chosen will provide sufficient heat output by checking the “Delta T”, please see below:

In our radiator catalogues AEL provide a heat output figure for each of our Radiators alongside our radiator dimensions, the output figures shown are based on a the water temperature entering and leaving the radiator.
If the water flow temperature in your heating system is different than the water temperature shown in the catalogue then you will need to calculate a new output figure, this is easily done , it just means multiplying the output figure in the catalogue by a figure shown on the correction chart provided at the bottom of this information sheet.


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Using an 80 oC water flow in temperature, and a 60 oC water flow out temperature the average temperature in the centre of the radiator is 70 oC.
If we take away the average room temperature of 20 oC from the 70 oC average temperature across the radiator we are left with a Delta T of 50.
If the "Delta t" in the catalogue is 50 oC and your system "Delta t" is 50 oC then it = 1 on the chart below which means it is perfect so just use the outputs shown in the catalogue.
If the system "Delta t" is more or less than 50 oC then look at the actual system temperature on the left hand side of the chart and multiply the output shown in the catalogue by the factor shown on the right hand side side of the chart, this will give you your new output for the radiator.
WATER TEMPERATURE CONVERSION FACTOR
5 0.050
10 0.123
15 0.209
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 1.549
75 1.694