Dust blocks air flow and reduces the efficiency of the system. Vacuum registers and make sure furniture does not block them . Bleed trapped air from hot water radiators . Once or twice a season, put a pan under the bleed valve and open it slowly until air comes out. Let the air escape until water drips out, then close the valve.
Some systems require a special tool called a radiator key to turn the valve.
Follow prescribed maintenance for steam heat systems , such as maintaining the right water level, removing sediment, and making sure that air vents are working. Be careful and check with your heating system technician about these measures because steam boilers produce high-temperature steam under pressure. Last updated December 31, 1995.