Abstract: An HVAC module having a reconfigurable bi-level duct system is disclosed. The air duct includes an air duct inlet in fluid communication with the HVAC module, an interior wall dividing the air duct into first and second air passageways, a bypass port enabling fluid communication between the first air and second air passageways. A downstream control valve disposed adjacent the bypass port and is configured to selectively direct air flow from one of the first and second air passageways to the other of the first and second air passageways. An upstream flow control valve is disposed adjacent to the inlet of the air duct, wherein the upstream flow control valve is configured to selectively direct air flow from the hot and cold chambers of the HVAC module to the first and second air passageways of the air duct.

Abstract: A method controls the discharge of temperature-conditioned air from a plurality of zone outlets of an automotive HVAC system via an open architecture multi-zone HVAC unit having a single blower fan, an evaporator downstream of the blower and a heater downstream of the evaporator, wherein each zone in the module includes a temperature mix door for proportioning hot and cold air, which is controlled by a separate Discharge Temperature Maintenance control (DTM control), and an output valve for controlling a zonal output flow rate. The output valve of each zone outlet is placed in an output valve position associated with a target resistance; and the single blower fan is operated at a minimum voltage required for generating a total requested blower output flowrate.

Abstract: HVAC module has an air inlet, an evaporator downstream of the blower and a heater downstream of the evaporator, and a rear mixing zone downstream of the evaporator and the heater, wherein a control valve prevents cold air from flowing back towards the hot air by regulating the pressure of the cold air. A method is devised to control anti-backflow control valve of such an HVAC module by the steps of reading pressure and temperatures at various points in the HVAC module; setting air flow and temperature discharge targets; calculating the resistance of the control valve and a bland valve; determining corresponding control valve and blend valve positions; and moving the control valve and blend valve to those corresponding positions.

Abstract: HVAC unit has a single blower fan, an evaporator downstream of the blower and a heater downstream of the evaporator, wherein each zone outlet includes a temperature mixing door for controlling portions of hot and cold air and an output valve for controlling a zonal output flow rate. A method is devised to control the discharge of temperature-conditioned air from a plurality of zone outlets of an automotive HVAC system via such an HVAC unit by the steps of reading an operator-requested zonal discharge blower level for each of the zone outlets; converting each zonal discharge blower level request to a zonal flowrate request; calculating a total requested output flowrate as a summation of all zonal flowrate requests; and adjusting a blower voltage to a minimum voltage required for generating the total requested output flowrate.

Abstract: An automotive HVAC system includes upper and lower mode cases configured to discharge separate streams of temperature-conditioned air into front and rear passenger zones. The system separates the inlet air into separate mixing chambers, and a third stream through a heater core. Blend doors control hot and cold air streams entering their respective mixing chambers. Operation is controlled by reading requested temperature, blower rate and mode for system zone outlet, converting requests to a flowrate, calculating total flowrate as a summation of all requests, employing a math model to calculate total zonal flowrate as a summation of all zonal flowrates, calculating a blower control error as a function of the difference between total blower request and total zonal flowrate, modifying the operating state using the calculated control error, positioning and resetting the mode valves into defrost, heater and vent openings, and resetting the mode valves.

Abstract: An open architecture HVAC module is disclosed having a housing defining an air inlet and at least two adjacent air outlets. An evaporator and a heater unit are disposed within the housing. A cold air chamber is defined between the evaporator and heater unit, and a hot air chamber is defined downstream of the heater unit. A partition extends into the cold and hot air chambers from an interior surface of the housing between the two adjacent air outlets. The partition is spaced from the evaporator and heater unit. The partition cooperates with the housing to define a first mixing chamber in fluid communication with the first outlet and a second mixing chamber in fluid communication with the second outlet. A blend valve is disposed in each mixing chambers. The blend valves are configured to selectively direct air flow from the cold and hot air chambers to the air outlets.

Abstract: A heating, ventilation, and air conditioning (HVAC) system for a vehicle includes an evaporator and a diffuser. The evaporator is configured to cool air passing through the evaporator. The diffuser is configured to direct a first portion of the air entering the diffuser through a first section of the evaporator, and direct a second portion of the air entering the diffuser through a second section of the evaporator. The evaporator and the diffuser are configured to cooperate such that air exits the first section at a first temperature and air exits the second section at a second temperature less than the first temperature.

Abstract: An HVAC module having a reconfigurable bi-level duct system is disclosed. The air duct includes an air duct inlet in fluid communication with the HVAC module, an interior wall dividing the air duct into first and second air passageways, a bypass port enabling fluid communication between the first air and second air passageways. A downstream control valve disposed adjacent the bypass port and is configured to selectively direct air flow from one of the first and second air passageways to the other of the first and second air passageways. An upstream flow control valve is disposed adjacent to the inlet of the air duct, wherein the upstream flow control valve is configured to selectively direct air flow from the hot and cold chambers of the HVAC module to the first and second air passageways of the air duct.

Abstract: An open architecture HVAC module is disclosed having a housing defining an air inlet and at least two adjacent air outlets. An evaporator and a heater unit are disposed within the housing. A cold air chamber is defined between the evaporator and heater unit, and a hot air chamber is defined downstream of the heater unit. A partition extends into the cold and hot air chambers from an interior surface of the housing between the two adjacent air outlets. The partition is spaced from the evaporator and heater unit. The partition cooperates with the housing to define a first mixing chamber in fluid communication with the first outlet and a second mixing chamber in fluid communication with the second outlet. A blend valve is disposed in each mixing chambers. The blend valves are configured to selectively direct air flow from the cold and hot air chambers to the air outlets.

Abstract: HVAC module has an air inlet, an evaporator downstream of the blower and a heater downstream of the evaporator, and a rear mixing zone downstream of the evaporator and the heater, wherein a control valve prevents cold air from flowing back towards the hot air by regulating the pressure of the cold air. A method is devised to control anti-backflow control valve of such an HVAC module by the steps of reading pressure and temperatures at various points in the HVAC module; setting air flow and temperature discharge targets; calculating the resistance of the control valve and a bland valve; determining corresponding control valve and blend valve positions; and moving the control valve and blend valve to those corresponding positions.

Abstract: A method controls the discharge of temperature-conditioned air from a plurality of zone outlets of an automotive HVAC system via an open architecture multi-zone HVAC unit having a single blower fan, an evaporator downstream of the blower and a heater downstream of the evaporator, wherein each zone in the module includes a temperature mix door for proportioning hot and cold air, which is controlled by a separate Discharge Temperature Maintenance control (DTM control), and an output valve for controlling a zonal output flow rate. The output valve of each zone outlet is placed in an output valve position associated with a target resistance; and the single blower fan is operated at a minimum voltage required for generating a total requested blower output flowrate.

Abstract: An automotive HVAC system includes upper and lower mode cases configured to discharge separate streams of temperature-conditioned air into front and rear passenger zones. The system separates the inlet air into separate mixing chambers, and a third stream through a heater core. Blend doors control hot and cold air streams entering their respective mixing chambers. Operation is controlled by reading requested temperature, blower rate and mode for system zone outlet, converting requests to a flowrate, calculating total flowrate as a summation of all requests, employing a math model to calculate total zonal flowrate as a summation of all zonal flowrates, calculating a blower control error as a function of the difference between total blower request and total zonal flowrate, modifying the operating state using the calculated control error, positioning and resetting the mode valves into defrost, heater and vent openings, and resetting the mode valves.

Abstract: HVAC unit has a single blower fan, an evaporator downstream of the blower and a heater downstream of the evaporator, wherein each zone outlet includes a temperature mixing door for controlling portions of hot and cold air and an output valve for controlling a zonal output flow rate. A method is devised to control the discharge of temperature-conditioned air from a plurality of zone outlets of an automotive HVAC system via such an HVAC unit by the steps of reading an operator-requested zonal discharge blower level for each of the zone outlets; converting each zonal discharge blower level request to a zonal flowrate request; calculating a total requested output flowrate as a summation of all zonal flowrate requests; and adjusting a blower voltage to a minimum voltage required for generating the total requested output flowrate.

Abstract: A heating, ventilation, and air conditioning (HVAC) system for a vehicle includes an evaporator and a diffuser. The evaporator is configured to cool air passing through the evaporator. The diffuser is configured to direct a first portion of the air entering the diffuser through a first section of the evaporator, and direct a second portion of the air entering the diffuser through a second section of the evaporator. The evaporator and the diffuser are configured to cooperate such that air exits the first section at a first temperature and air exits the second section at a second temperature less than the first temperature.

Abstract: A vehicle heating and cooling system has a distribution duct separated into two channels by a baffle for supplying separate air streams to the passenger and driver sides of the vehicle compartment. Two temperature control doors associated with the heater core and evaporator separately admit an air mix to the two channels for independent control of driver and passenger side temperature. Optionally a single door is used in place of the two temperature control doors so that at the time of manufacture the system can be configured as a single zone system. A rear air discharge opening is provided in one of the channels to supply a duct leading to the rear seat region of the vehicle compartment.