In such a system hot air and cool air if there is also a central air system in place is blown out into rooms to provide heat or cool via floor vent , which are essentially metal plates with holes or openings in them to allow the “treated” air to come through. Heat registers are vent covers that cover the hole in the wall or floor where the duct enters the room. Louvres, or dampers, are often attached to the back of a heat register. … A grille has no damper to control air flow, so air is left to flow freely. Grilles do not have the damper normally found on registers.
A register is a grille with moving parts, capable of being opened and closed and the air flow directed, which is part of a building’s heating, ventilation &air conditioning (HVAC) system. The placement and size of registers is critical to HVAC efficiency. Register dampers are also important, and can serve a safety function.













