Though many people in our neighborhood have updated their heating systems, we've never considered it. Cast iron radiators, which we have in every room of our house, are surprisingly efficient. If you have unpainted radiators in your home, most home heating experts recommend keeping them that way. Unfortunately, all of ours were painted when we moved in.
If you're going to do anything with a painted radiator, it's important to first make sure that you know what kind of paint you're dealing with. Since your radiator is likely in an older home, it could be covered in lead paint. If so, it's best to research proper ways to protect yourself from that hazard
If your radiator is lead-free, you basically have two choices. You can either sandblast the beast, something we've not yet tried. Or you can just grab a piece of sandpaper and get started. Sandblasting is by far the best quality option, but if you've ever tried removing a cast iron radiator, you'll know why we chose the sandpaper. Those things are heavy
and removing them requires draining your entire system.
Once you've decided on your method, use a wire brush to scrub away all dust, grime, and loose chips. Sand well, and you're ready to paint
You have a few choices when it comes to paint. You can choose to spray on a high-heat paint if you like, but in hot water systems such as ours, the radiators don't get hot enough to require it. Instead, we use an oil-based primer followed by the oil-based color of our choice. Latex is not recommended because it can lead to rusting.
Though there's plenty of debate on the topic, there doesn't seem to be a consensus on color. Some people believe that color affects the efficiency of the radiator, while others say the effect is negligible. What most experts DO agree on is that metallic paint is not a good choice, as it reduces the radiator's ability to heat a room. If you like the look of the old, unpainted radiator but yours is painted, you can recreate it by using a bronzing technique.
Finally, we've experimented with different types of brushes
to hit all the tight spaces in a radiator, but have yet to come up with one we love. Has anyone out there painted a radiator and found a tool that can get into all the hard-to-reach places?