There are some simple ways to improve steam heat radiator efficiency that require little or no money. All you need is some motivation, a little elbow grease or a few simple tools.
Allow for Circulation
Move furniture or other large items that block your radiator’s air circulation. You must allow several inches of space in front, on top and on the sides of the radiator for proper circulation of heat.
Keep it Clean
Clean any accumulated dust from the surface of the radiator. Dust acts as an insulator which slows heat radiating from the surface and into surrounding areas, reducing heat efficiency.
Make a Reflector
Radiators are generally placed on outside walls, which are cold. They absorb much of the heat being given off from the radiator. To make the steam heat more efficient, measure a piece of cardboard and cut it to the same size as the radiator. Cover the front of the cardboard with aluminum foil, shiny side out, and tape it in place. Put it against the wall behind the radiator. This will cause the heat to be reflected back into the room instead of heating the wall.
These simple measures will improve your steam heat radiator efficiency noticeably.