The utility model discloses a fan portion dress and gas heater, wherein, this fan portion dress includes: the spiral case is equipped with in, along the fore -and -aft direction separates the smoke exhaust cavity and heat dissipation chamber who arranges, the heat dissipation chamber is located the smoke exhaust cavity rear, the impeller of discharging fume is located in the smoke exhaust cavity,discharge fume axial along the fore -and -aft direction setting of impeller, the motor is including motor body and pivot, motor body is located the spiral case rear side, the pivot runs through the heat dissipation chamber is just stretched into smoke exhaust cavity, the pivot cover of impeller of discharging fume is established and is fixed in the pivot, and radiating impeller, locate the heat dissipation intracavity, be equipped with air intake and air outlet on the chamber wall in heat dissipation chamber, radiating impeller locates between air intake and the air outlet, so that the heat dissipation intracavity forms a scattered hot air duct. The utility model discloses can effectively improve the gas heater systematic radiating effect of discharging fume, reduce the temperature of motor during operation, the life of extension motor.