The G4-73 and Y4-73 boiler fans are designed for use in fan systems serving 2 to 670 T/h steam boilers in thermal power plants. The G4-73 model can also be used for general mine ventilation. When serving as a ventilator, the G4-73 conveys air with a maximum temperature not exceeding 80°C. When used as an induced draft fan, it conveys flue gas with a maximum temperature not exceeding 250°C.

The G4-73 is equipped with a Type A replaceable motor. General ventilation motors are manufactured to Class E standards, while high-temperature motors are constructed using heat-resistant materials. To aid heat dissipation, a cooling fan wheel is added to the extended shaft between the impeller and the motor housing, effectively blocking heat transferred from the impeller. The G4-73 features a straightforward design.