Air Distribution Control Topics covered in this presentation: Single and dual distribution assemblies Blend-air and stacked core re-heat systems Ducts and louvers Single & dual systems ClassAct SRS enabled.

Temperature control lever Introduction Air distribution systems are used to direct air flow into the passenger compartment. Airflow is controlled by flaps and mixing doors. The A/C control panel is mounted in the instrument cluster. Temperature control lever The airflow through the heater core is controlled by the temperature selector. A multi-speed fan is used to change the airflow rate. Fan control Next >

Air Distribution Section Typical Heater & A/C Assembly Layout A single distribution heater system, shown below, is split into three sections. Air Inlet Section Plenum Section Air Distribution Section Filtered fresh air in Air to defrost panels Evaporator Heater core Fan Intake door Air mix (blend) door Floor air out Recirculated air in Air to panel outlets Next >

Question 1 In a single distribution heater system, the fan is situated in the plenum section. Is this true or false? Answer True or False. Correct Answer = F

Air Distribution Assembly Location The air distribution assembly is normally located at the back of the engine compartment, and is fixed to the bulkhead. Heater and A/C controls Fan housing Evaporator housing Air distribution assembly with heater core System hoses Engine Compressor Condenser Next >

Question 2 Where is the air distribution assembly normally located? A) Behind the front grill B) At the back of the engine compartment C) Below the engine bulkhead Correct Answer = B D) Behind the dashboard

Air Flow Through Heater & A/C Assembly Defrost air out Filtered fresh air in Air mix (blend) door Fan Intake door Evaporator Floor air out Recirculated air in Arrows show the air flow through and around the heater and A/C assembly. Heater core Next >

Question 3 Where does defrost air normally go to? A) Floor level B) The windscreen C) The evaporator Correct Answer = B D) The seats

Blend-Air Reheat System The blend-air reheat system works by re-heating and mixing cooled, dried air from the evaporator, using the blend door. Lines to A/C system Cold air from evaporator Filtered fresh or recirculated air in Air blend door Evaporator Heater core Hot water lines from engine cooling system to heater core Hot air from heater core Blended air to vehicle interior Next >

Stacked Core Reheat System The stacked core re-heat system works by controlling the temperature of the heater core. Lines to A/C system Filtered fresh or recirculated air in Evaporator Cold air from evaporator Heater core Hot water lines from engine cooling system to heater core Reheated air to vehicle interior Heater valve (temperature control) Next >

Question 4 Which is the correct sequence for operations on the air in an a/c system? A) Cooled, heated, filtered B) Heated, cooled, filtered C) Filtered, cooled, heated Correct Answer = C D) Heated, filtered, cooled

Temperature control lever Typical Control Panel/Head The typical panel below contains all the controls and information for the vehicles heating and ventilation. Temperature control lever Air conditioning control lever Air conditioning on/off switch Air distribution control lever Fan control Next >

Control Panel/Head Cable Connections The control levers and switches are connected to the distribution controls behind the control panel. Air conditioning control lever Temperature control cable Temperature control lever Fan control connector Air distribution control cable Air conditioning on/off switch connector Air conditioning control cable Next >

Heating System Inlets and Outlets Inlet and outlet ducts are used to recycle and change the air within the passenger compartment. Windscreen defroster nozzle Side window outlet Filtered fresh air in Side window outlet Instrument panel outlets Floor outlets Instrument panel outlets Re-circulated air in Next >

Louver Construction Outlet louvers are used to control and direct heating and ventilation air flow into the passenger compartment. Air door control wheel Air control door Louver housing Louver Louver direction control Next >

Front & Rear Passenger Compartment Ducts Compartment ducts are used to direct heating and ventilation air around the vehicle, luxury vehicles have very complex systems. Front compartment ducts Defroster outlets Side window outlet Instrument panel outlets Side window outlet Rear compartment ducts Rear compartment outlets Next >

Question 5 What is the name of the parts of the vehicle used to control the flow of air into the passenger compartment? A) Duct B) Louver C) Outlet Correct Answer = B D) Nozzle

Dual-Zone Distribution System Dual-zone heating and ventilation distribution systems allow for personal settings, when selecting heating and ventilation temperatures. Driver defrost door Driver windscreen outlet Filtered fresh air in Driver floor outlets Driver air mix (blend) door Driver mode door Driver panel outlets Heater core Evaporator Passenger windscreen outlet Passenger panel outlets Fan Passenger defrost door Passenger air mix (blend) door Passenger floor outlets Passenger mode door Recirculated air in Next >

Summary You should now be aware of: Single and dual distribution assemblies Blend-air and stacked core re-heat systems Ducts and louvers Single & dual systems End >