Abstract: An air-conditioning system for air-conditioning an interior of a vehicle may include a fan for driving air. The system may include a control device that may include a circulating air inlet for drawing in circulating air from the interior, a fresh air inlet for drawing in fresh air from an environment of the vehicle, and an air outlet. The control device may include a control valve adjustable between a circulating position and a fresh air position. The control valve may include at least one non-return check valve. The non-return check valve may permit a flow to pass through the control valve in one direction and block the flow in an opposite direction.

Abstract: An electric heater is provided that includes at least two groups of heating elements which change their temperature by electrical power consumption, comprising a control unit with two switch arrangements such that the first switch arrangement includes at least two power switches for switching the at least two groups of heating elements in a High-side connection and such that the second power switch arrangement includes at least two switches for switching the at least two groups of heating elements in a Low-side connection.