How to maintain radiators and increase their efficiency? How do you fix a noisy radiator?

Heat from a hot-water or steam heating system is released through a cast-iron radiator or the metal fins of a convector radiator. At the beginning of each heating season, remove covers or grills to vacuum the cast-iron tubes or metal funs. Bleed hot-water radiators or convectors.

Straighten bent convector fins with broad-nose pliers. Make sure the covers have space for cold air to enter at the bottom and for heated air to flow out the top. Add openings if needed; remove obstructions, such as draperies, that block air flow.

You can increase the heat delivered to a room by attaching aluminum foil to the wall behind a radiator. Metallic paint on a radiator absorbs heat. Repaint the radiator with nonmetallic, preferably flat black, paint (you need not remove the old paint); paint the inside of its cover black.

If a steam radiator makes a banging sound, check its slant with a carpenter’s level. In a one-pipe system, the radiator should tilt slightly toward the inlet pipe to allow water condensed from cooling steam to flow back to the boiler. In a two-pipe system, it should tilt toward the outlet pipe. To adjust a radiator’s slant, lift it slightly and use a mallet to drive wood shims under the appropriate legs. A partially opened inlet valve also creates noise. Make sure the valve is completely opened or closed.