The definition of a parallel fan is a type of HVAC fan that is designed to move air at a constant rate even when the pressure in the system changes. Parallel fans use multiple motors and blades that rotate in the same direction to maintain a constant air flow. They are often used in air conditioning systems as they are highly efficient and require minimal maintenance. Parallel fans are also commonly used in industrial settings to move air or exhaust fumes. The fan blades are designed to rotate in such a way that the air is evenly distributed throughout the system. This ensures that the temperature remains consistent and that the system runs at maximum efficiency. Furthermore, due to their design, parallel fans are also much quieter than other types of fans. This makes them ideal for use in residential and commercial applications, as they can be installed in areas where noise levels need to be kept to a minimum. Overall, parallel fans are an excellent choice for any application, as they are easy to maintain, highly efficient, and relatively quiet