Functional Segments of Comfort AHU
Updated: May 6
The main functions of a comfortable AHU (Air Handling Unit) are to regulate the temperature of the air, cool and heat the air, perform simple filtration, and adjust humidity with less requirements. This type of AHU does not have very strict air volume requirements, as long as the air volume can carry out cooling (heating) of the room.
There are 2 common functional segment combinations for comfort AHUs:
This combination is the most common comfort AHU with the lowest configuration. The filter can be general nylon mesh, low grade (G3, G4) plate type or bag type filter. The filter is installed externally, generally pulled from the side, and some ceiling units will be pulled from the bottom. Coils are generally selected according to refrigeration conditions. Fans are generally ordinary centrifugal fans. Belt drive or external rotor fan can be used.
This type of unit is suitable for all return air conditions, fresh air conditions, and mixed conditions. Under mixed working conditions, fresh and return air are generally mixed in the pipeline before entering the unit.
There is a mixing section, which facilitates the connection of air inlet pipes, the control of the new return air ratio, and the installation and replacement of filters. For other occasions with more requirements, the following functional segments can be added:
① Bag filter section:
In addition to configuring low grade primary filtration, add a relatively high grade (F5-F7) bag filter. Generally, it is equipped behind a plate filter and can be installed on a common slide with the plate filter.
② Activated carbon filtration section:
For some high-end applications, activated carbon filtration can remove odors and smoke from the air.
③ Humidification section:
For AHU in comfort occasions, considering the cost, wet film humidification or high-pressure spray humidification and other humidifiers with lower prices are generally used. This type of humidifier has a relatively low efficiency, but is sufficient to "make the air feel comfortable and not very dry.".
④ Silencing section:
In places with high noise requirements, such as hospitals, conference rooms, theatres, radio stations, etc., noise reduction sections are usually added. Mufflers for comfort situations generally use a muffler in the form of orifice plates+glass wool.