The role of DC crossflow fans in ventilation and exhaust systems is to achieve air circulation and exhaust by generating airflow. Here are its specific functions:

1. Ventilation: DC crossflow fans are used in ventilation systems to introduce fresh air into the room or specific area. They draw outdoor air into the building or room by generating airflow to improve air quality, increase oxygen supply and reduce the accumulation of dirty air.

2. Exhaust: DC crossflow fans play the role of exhausting dirty air in exhaust systems. They generate airflow to exhaust indoor dirty air, odor, moisture, harmful gases or smoke, etc. outside the building or room to keep the air fresh and the environment comfortable.

3. Air circulation: DC crossflow fans can evenly distribute indoor air throughout the space by circulating air. This helps to maintain a balanced indoor temperature and consistent humidity, avoiding localized heat or humidity.

4. Temperature regulation: DC crossflow fans can be used for temperature regulation, especially when used in conjunction with heating or cooling systems. They can facilitate heat transfer and even heat distribution to achieve temperature regulation and control.

5. Humidity Control: The operation of DC crossflow fans can help regulate humidity. By introducing fresh air or exhausting moisture, they can assist in controlling indoor humidity and prevent moisture accumulation and mold growth.

In general, the role of DC crossflow fans in ventilation and exhaust systems is to promote air flow, maintain fresh air, balance temperature and control humidity. They are very important for creating a comfortable indoor environment, providing healthy air quality, and increasing the comfort of the overall living and working environment.