Carl - does a black car get hotter sitting in the sun than a white one? how does the car know what color it is?
I would "guess" that the factory employed known principles of thermodynamics to choose
flat black - prolly even consulted some physicists in the process, or at least someone who understood
black body heat transfer principles ..... interesting name that
as I mentioned above, the tank isn't where the primary heat transfer happens so it isn't too important, notice that modern rads even have plastic tanks - but the surface color of the fin/tube part does make a difference, and the surface
texture as well, the very smooth surface of gloss black doesn't work nearly as well - in addition, the thickness of a gloss paint adds a measure of insulation
Bill
