In article ,
Brian Gaff wrote:
I don't think you quite got the question or maybe you are being
diplomatically thick.

I imagine what he means is, how much does the extra surface area in
those old cast radiators get more heat into a room over the normal
ones. Obviously if they were so efficient as to make the hot water cold
no other radiator would get hot would it!

It's the wrong word to use - strictly speaking. Normally efficiency as
regards a heater would be energy in versus heat out.

As you said what's wanted is the heat output of the various types of rad.

--
*And the cardiologist' s diet: - If it tastes good spit it out.

Dave Plowman London SW
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