Painting Radiators...

Did any of you read the study that was published by NIST when it was just the Bureau of Standards in 1924 that I posted above that addresses this specific subject? There is the data. Color is not relevant for dissipative properties alone.

 

Shiny silver yes, but if you look at the fin material of a modern aluminum radiator closely you will see that it is not shiny at all but a very dull material that is actually designed to shed heat at it's greatest point. Probably splitting hairs on this and not likely to make 2 degrees of difference on the temp gauge either way.

 

I'd venture a guess that the extra layer of paint would hinder the heat transfer coefficient across the tube wall and therefore reduce the rate of heat transfer. The convection/conduction is the primary mode of heat transfer, radiation is a more minor player IMHO..

 

Black with seven slot grille…