Disclosed are a fan apparatus and an air conditioner outdoor unit. The fan apparatus includes: a first wind wheel and a second wind wheel, axially arranged in an interval. A spacing S1 between the first wind wheel and the second wind wheel satisfies S1<(H1+H2)/2, where H1 is a length of the first wind wheel along the axial direction, and H2 is a length of the second wheel along the axial direction.

A heat exchanger includes a core including a plurality of tubes and a plurality of air passages, an air inlet portion in fluid communication with the air passages, and an air outlet portion in fluid communication with the air passages. The tubes and the air passages are alternately arranged to be parallel with each other. The core extends along a core plane defined by the tubes and the air passages. The core is disposed such that the core plane is parallel to a vehicle horizontal plane. Outside air flows through the air passages in a first direction. Thermal medium flows through the tubes in a second direction opposite to the first direction. The air inlet portion is open at a front side of the vehicle or a lateral side of the vehicle. The air outlet portion is open at the front side of the vehicle or the lateral side of the vehicle.

An outdoor unit has a frame that carries a ground grooming or working implement, a traction drive, and a cooling fan, all of which comprises loads on a prime mover. A power management controller automatically reduces an operational speed of the traction drive when prime mover droop is present. The cooling fan cools two cooling fluids. The controller stores data representing variable fan speeds for cooling each cooling fluid in both normal and above normal temperature ranges and for use when prime mover droop is present. The controller uses the highest fan speed required for cooling the cooling fluids in the normal range unless the droop fan speed is lower in which case the lower droop fan speed is used but only to the extent that the lower droop fan speed is not lower than the highest fan speed required for cooling the cooling fluids in the above normal temperature range.

A cooling device includes a casing having a peripheral wall, a plurality of heat exchangers disposed side by side so as to extend transversely in the casing, and a plurality of fans opposed to the plurality of heat exchangers. The casing has a plurality of baffles that extend from the heat exchanger group side toward the cooling fan group side in a space surrounded by the peripheral wall and is arrayed in an arrangement direction of the plurality of heat exchanges. A one side end portion of each baffle is positioned on a boundary between two mutually adjacent heat exchangers or on one of the heat exchangers. The fifth fan is disposed at such a position as to be opposed to one of the plurality of baffles, and other fans are disposed at a position between the peripheral wall and a baffle or between the plurality of baffles.