Vehicle rooftop air conditioner

An air-conditioner mounted on a roof of a recreational vehicle having an interior space and one or more openings in said roof for delivery of conditioned air to said interior space and return of indoor air to said air conditioner, said air conditioner comprising:

• a base pan positioned on said roof and having one or more openings forming a return air intake and a conditioned air outlet in communication with said one or more openings in the roof;
• a compression refrigeration system on said base pan and comprising a compressor, evaporator and condenser operatively coupled together;
• a first enclosure forming a conditioned air flow plenum above said base pan, said evaporator being located within said first enclosure and being operable for heat transfer with an indoor air stream flowing therethrough;
• a centrifugal fan positioned within said first enclosure and operable to draw indoor air from the interior space through said return air intake, through the evaporator and then into the centrifugal fan for tangential discharge in a substantially horizontal plane;
• a scroll positioned about the centrifugal fan and forming an air passage for receiving the air tangentially discharged from the centrifugal fan and redirecting it in a downward direction to the conditioned air outlet for delivery into the interior space;
• a second enclosure forming an outdoor air flow plenum above said base pan, said condenser being located within said second enclosure and being operable for heat transfer with an outside air stream flowing therethrough;
• a second fan positioned and operable to draw air through said condenser;
• a motor driving said centrifugal fan and said second fan;
• a vertically extending drive shaft extending from opposite ends of the motor and wherein said centrifugal fan is mounted on said drive shaft at one end of the motor and said second fan is mounted on said drive shaft at an opposite end of the motor;
• and
• a shroud covering at least said first and second enclosures and having a top and sides, said top being spaced a preselected vertical distance above said base pan.

A method of circulating conditioned and outdoor air in an air conditioner mounted on a roof of a recreational vehicle having an interior space, said air conditioner having a base pan and a covering shroud having a top spaced a preselected vertical distance above said base pan, said method comprising the steps of:

• rotating, about a common vertical axis, a centrifugal fan positioned within an evaporator enclosure and an axial fan positioned in a condenser compartment;
• causing, as a result of said rotating of the centrifugal fan, indoor air to be drawn from said interior space through a return air inlet into said evaporator enclosure and then through an evaporator for heat exchange and cooling of said air, said cooled air then being drawn into a center opening of said centrifugal fan and then being expelled tangentially from said centrifugal fan in a substantially horizontal plane;
• capturing at least some of said tangentially expelled air from said centrifugal fan in a surrounding scroll and redirecting it in a downward direction into said interior space for cooling thereof;
• directing, as a result of said rotating of the axial fan, outdoor air through a condenser located in said condenser compartment for heat exchange therewith and then exhausting said outdoor air through said shroud.