Abstract: An expandable filter cartridge for installation in the filter housing of a vehicle includes a rectangular frame having top and bottom legs and side legs. The side legs of the frame are extendible and retractable in length to configure the frame between a relatively compact size for insertion into the filter housing and a relatively expansive size for spanning the interior dimensions of the filter housing. The filter cartridge is installed by being inserted while in its compact configuration into a slot in the filter housing and, once inside, expanded to span the interior dimensions of the housing.

Abstract: A method of drying condensate from the heat exchanger of a vehicle's air conditioning system after operation in order to thwart odor buildup is provided. The method comprises first determining that the engine of the vehicle has been switched off and that the air conditioning system of the vehicle was in operation prior to the engine being switched off. If these two conditions are met, the blower of the vehicle's air conditioning system is operated on a predetermined time schedule to draw air through the heat exchanger and through the air conditioning duct work to dry condensate from the heat exchanger and from interior surfaces of the duct work. In this way, the growth of fungus and bacteria that cause odor is thwarted.