An exhaust fan assembly is provided for expelling contaminated air from a building. The assembly includes a plenum, a fan assembly attached to the plenum, and a windband mounted on top of the fan assembly. The fan assembly is constructed of cylindrical outer and inner walls which define a bearing chamber and surrounding annular space. A fan driven by a shaft extending downward from the bearing chamber draws exhaust air from the plenum and blows it up through the annular space to a nozzle at the top of the fan assembly.

A fan unit a nozzle assembly including a plurality of nozzles configured to receive an air flow and to expel the air flow through a plurality of outlets corresponding to the plurality of nozzles. A controller configured to control a longitudinal movement of a nozzle of the plurality of nozzles based on an operating condition associated with the fan unit.

A fan unit a nozzle assembly including a plurality of nozzles configured to receive an air flow and to expel the air flow through a plurality of outlets corresponding to the plurality of nozzles. A controller configured to control a longitudinal movement of a nozzle of the plurality of nozzles based on an operating condition associated with the fan unit.

Provided is an exhaust port member (7) having an inlet port (811) into which combustion exhaust gas flows; an exhaust port (77) through which the combustion exhaust gas is discharged to an outside; an exhaust passage (P) in which the combustion exhaust gas flows from the inlet port (811) toward the exhaust port (77); and a space part (9) which is located adjacent to a downstream end exhaust passage part (Pz) positioned at a downstream end of the exhaust passage (P) via a partition wall (781) defining the downstream end exhaust passage part (Pz), wherein the space part (9) has an upstream opening (90) on an upstream side thereof, the combustion exhaust gas flowing through the exhaust passage (P) flows into the space part (9) through the upstream opening (90), and the space part (9) is closed except for the upstream opening (90).

Provided is an exhaust port member (7) having an inlet port (811) into which combustion exhaust gas flows; an exhaust port (77) through which the combustion exhaust gas is discharged to an outside; an exhaust passage (P) in which the combustion exhaust gas flows from the inlet port (811) toward the exhaust port (77); and a space part (9) which is located adjacent to a downstream end exhaust passage part (Pz) positioned at a downstream end of the exhaust passage (P) via a partition wall (781) defining the downstream end exhaust passage part (Pz), wherein the space part (9) has an upstream opening (90) on an upstream side thereof, the combustion exhaust gas flowing through the exhaust passage (P) flows into the space part (9) through the upstream opening (90), and the space part (9) is closed except for the upstream opening (90).