S Bengi wrote:Wonering how we could run cold water thru those radiators in the summer, to cool the house.
You don't really want that.
The mentioned condensation is not just a nuisance of emptying a little distilled water, but usually these radiators are from materials that do rust.
By being covered often in oxygen rich water they can rust. Paint or no paint. (Its different on the inside, since the heating water gives up its oxygen once and receives very little oxygen later.)
Also it is not a nice kind of cooling, it is ineffective in making comfortable air. But if you had floor wall or ceiling heating, you cold install a heat exchanger in your system and cool the water in the system.
Care must be taken to not to cool the surfaces under certain temperature, since even a small amount of condensation can let mold to appear.