Abstract: A door decelerator system reduces or prevents undesirable limits of audible door noise in an HVAC unit. The system includes a door, movable between end or stop positions; and a kinematics lever connected to the door at a common axis of rotation or the kinematics lever having a deceleration axis common with the door, the kinematics lever having a deflection area incorporated therein. A rigid rib is incorporated in a housing of the HVAC unit, the rigid rib disposed in compressive contact with the deflection area at least as the kinematics lever reaches an end of travel. The deflection area is physically separable from the rigid rib.