Radiator Output Calculation (BTU/KW) Help! (bestheating.com)

[OC75]

Hi, I am in the midst of choosing radiators for a new build.

There are various calculator tools available online, giving quite a range in results on what I require for each room. The tools do not specify whether they are based on T30, T50 or whatever.

I am considering the Milano Windsor range from bestheating.com, so I have used their online tool and looked for radiators to meet the output required.

On bestheating.com each radiator has a BTU/KW listed in the product summary (example at link below)

However when you open up the further details for each rad it has BTU/KW's listed for T30 & T50 which are much lower.

Which BTU/KW figure should I be going by?

What calculator tool is reliable?

Are the radiator suppliers/outlet BTU/KW ratings reliable?

www.bestheating.com/radiators/shop-by-brand/milano/windsor.html?gclidpla_prodid=3958&gclid=CjwKCAjw-OHkBRBkEiwAoOZql-UmpgS0Po0xQbRbofZ2MWMLcMATXYagwPYvKC241ACpEnbeNuNQ8RoC4eQQAvD_BwE&gclsrc=aw.ds

This looks like a good explanation of what this means. Appears to depend on your boiler output:

budgetradiators.co.uk/delta-t-heating-conversion-factors

Bestheating.com list their outputs at T60 - not T50 (the T50 figure is available in the product details blurb lower down underneath each radiator listing as you’ve discovered) I assume to make them look more powerful than they actually are.

I found traderadiators.com better value for comparable outputs at T50. Their own brand column range are almost identical to Milano Windsor. As I understand it most boilers in UK should be running at T50 (though of course you can adjust this to T60 if you want but your fuel bills will also increase accordingly).