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Air Handling Unit

  • Y. H. Venus LunEmail author
  • S. L. Dennis Tung
Chapter
Part of the Green Energy and Technology book series (GREEN)

Abstract

Air handling unit (AHU) is one of the most important equipments in HVAC (heating, ventilation, and air-conditioning) system particularly in large-scale buildings for providing both heating and cooling for multiple zones. This chapter starts with a discussion on AHU and indoor air quality. AHU operations not only significantly impact supply air temperature and humidity levels, but also the energy consumed for heating, cooling, and ventilation. It is essential to implement measures to reduce energy consumption. Various operating modes and ventilation systems of AHU are also discussing. AHU dehumidification by using direct expansion (DX) coil and rotary desiccant dehumidifier is investigated. Furthermore, hybrid systems on integration of rotary desiccant dehumidification with AHU unit and primary handling unit are examined. To illustrate the design of AHU system, a case study on cold vault is presented.

Keywords

Ventilation Indoor air quality Operating mode AHU configuration Dehumidification and humidification Energy recovery system Cold room 

Nomenclature

F

Flow rate

H

Humidity

O

Output

T

Temperature

Subscript

cc

Cooling coil

ea

Exhaust air

fa

Fresh air

hc

Heating coil

ma

Mixing air

ra

Return air

oa

Outdoor air

sa

Supply air

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Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.Sustainable Energy LimitedHong KongPR China
  2. 2.Sustainable Energy LimitedHong KongPR China

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