A vehicular ventilation module, for use in combination with a heating, ventilation and air conditioning (HVAC) system, comprising: a return air duct having a return air inlet and a return air outlet downstream of the return air inlet; a fresh air duct having a fresh air inlet and a fresh air outlet downstream of the fresh air inlet; a heat exchanger thermally coupled to the return air duct and the fresh air duct, wherein the heat exchanger is upstream of the return air outlet and the fresh air outlet, and downstream of the return air inlet and the fresh air inlet; a first wall, comprising a first door, separating an upstream portion of the return air duct upstream of the heat exchanger and an upstream portion of the fresh air duct upstream of the heat exchanger; a second wall, comprising a second door, separating a downstream portion of the return air duct downstream of the heat exchanger and a downstream portion of the fresh air duct downstream of the heat exchanger; wherein the first and the second door (212, 206) are operable to selectively open and close to allow air downstream and/or upstream of the heat exchanger to pass between the fresh air duct and the return air duct; characterized in that the module comprises: a third door coupled to the return air inlet; a sensor configured to communicate climate-based information to a controller; controller configured to, based on the climate-based information communicated from the sensor via the controller, open the first door so that a first portion of air received through the fresh air inlet is drawn into the return air duct and drawn through the heat exchanger in the return air duct, and a second portion of the air received through the fresh air inlet is drawn through the heat exchanger in the fresh air duct; and wherein the controller is further configured to open one or more of the first and second doors (212, 206), and at least partially close the third door to modulate an amount of the return air introduced through the return air inlet;and wherein the return air outlet is configured to be coupled with the HVAC system of a vehicle to provide air to the HVAC system. a return air duct having a return air inlet and a return air outlet downstream of the return air inlet; a fresh air duct having a fresh air inlet and a fresh air outlet downstream of the fresh air inlet; a heat exchanger thermally coupled to the return air duct and the fresh air duct, wherein the heat exchanger is upstream of the return air outlet and the fresh air outlet, and downstream of the return air inlet and the fresh air inlet; a first wall, comprising a first door, separating an upstream portion of the return air duct upstream of the heat exchanger and an upstream portion of the fresh air duct upstream of the heat exchanger; a second wall, comprising a second door, separating a downstream portion of the return air duct downstream of the heat exchanger and a downstream portion of the fresh air duct downstream of the heat exchanger; wherein the first and the second door (212, 206) are operable to selectively open and close to allow air downstream and/or upstream of the heat exchanger to pass between the fresh air duct and the return air duct; characterized in that the module comprises: a third door coupled to the return air inlet; a sensor configured to communicate climate-based information to a controller; controller configured to, based on the climate-based information communicated from the sensor via the controller, open the first door so that a first portion of air received through the fresh air inlet is drawn into the return air duct and drawn through the heat exchanger in the return air duct, and a second portion of the air received through the fresh air inlet is drawn through the heat exchanger in the fresh air duct; and wherein the controller is further configured to open one or more of the first and second doors (212, 206), and at least partially close the third door to modulate an amount of the return air introduced through the return air inlet;and wherein the return air outlet is configured to be coupled with the HVAC system of a vehicle to provide air to the HVAC system. a third door coupled to the return air inlet; a sensor configured to communicate climate-based information to a controller; controller configured to, based on the climate-based information communicated from the sensor via the controller, open the first door so that a first portion of air received through the fresh air inlet is drawn into the return air duct and drawn through the heat exchanger in the return air duct, and a second portion of the air received through the fresh air inlet is drawn through the heat exchanger in the fresh air duct; and wherein the controller is further configured to open one or more of the first and second doors (212, 206), and at least partially close the third door to modulate an amount of the return air introduced through the return air inlet;and wherein the return air outlet is configured to be coupled with the HVAC system of a vehicle to provide air to the HVAC system.