If your radiators no longer work, but have never been removed from your home, you’re in luck—you can skip to Step 2.
Turn off the radiator and let it cool down before painting. Applying paint to a hot radiator will result in improper paint adhesion. You should be able to easily find the valve that controls the steam that heats the radiator and turn it to the off position. Generally, a radiator will cool down in approximately 30 minutes to an hour. When the radiator is still warm or close to room temperature, you should be able to start painting without affecting your finished results.