Heating & ventilation (Ducts): Description and operation

Ducts

The rear footwell ducts extend along each side of the transmission tunnel and vent into the rear footwells from below the front seats. The outer face level ducts attach to the underside of the fascia and connect to the vent assembly at each end of the fascia. The windscreen/side window ducts connect to a duct integrated into the top of the fascia.

Vent assemblies

The vent assemblies allow occupants to control the flow and direction of face level air. Each vent assembly incorporates a thumbwheel to regulate flow and moveable vanes to control direction.

CONTROLS

Rotary knobs are installed on the centre console to control air distribution, blower speed and air temperature. The air distribution and temperature knobs operate cables connected to the control flaps in the heater assembly. The blower speed knob operates a rotary switch in the blower’s electrical circuit.

Heating and ventilation controls

OPERATION

Air flow through the heater assembly is directed to the outlets selected by the distribution control knob. The temperature of the air from all except the face level vents depends on the setting of the temperature control knob. Hot air is available from the face level vents only when the temperature control knob is at the maximum heat setting. As the temperature control knob is turned towards cold, the temperature of the air from the face level vents rapidly decreases to ambient (non A/C vehicles) or evaporator outlet temperature (A/C vehicles). The forward speed of the vehicle and the setting of the blower control knob determines the volume of air flowing through system.