Valve driving mechanism for an HVAC system

An air conditioning system of the present invention for an automotive vehicle includes a housing having at least two sections connected by two side by side air passage. A blower device of the air conditioning system discharges air into the housing. An evaporator is disposed in one of the sections for taking heat from the air discharged from the blower device to produce cool air. A heater is disposed in the other section positioned downstream of the evaporator for adding heat to the cool air to produce warm air. First and second sliding valve plates mechanically communicated with a driving mechanism of the present invention are supported by the housing for selectively closing the two side by side air passages thereby regulating air flow of cool and warm air.