Variable Air Volume (VAV) System to achieve better Indoor Dissertation

Variable Air Volume (VAV) System to achieve better Indoor Environmental Quality for a commercial Building & energy saving - Dissertation Example The main reason for these functions like heating, ventilation, cooling, and air-conditioning is to make occupants of rooms comfortable (Awbi, 2003). VAV system is one of the HVAC applications and its main purpose is to reduce energy cost as well as maintenance cost. The use of VAV process contains two main components and the components are the room and the VAV damper. The main VAV air handling system is the embedded HVAC system which most of the times are invisible. It is this system that is responsible for delivery of conditioned air to the whole building or structure. The use of this type of system has two merits and the merits are based on the constant volume that is found within the system. This system has the fan control capacity unlike other systems like CAV and the fan control capacity enhances reduction of the used amount of energy. CHAPTER ONE 1.1 INTRODUCTION Variable Air Volume also commonly known as (VAV) system is a kind of ventilation, heating, and air-conditioning devi ces that use a supply duct of fresh air and gives out hot or cool air as the supply air. The air which is being supplied to this device most of the time has constant temperature and therefore, the resultant airflow always varies for the achievement of the fall and rise of the losses or gains characterized with thermal zone. Most of the VAV systems have two primary merits and the merits are due to the constant volume within the system. The system has a fan control capacity which is capable of reducing the amount of energy consumed through the fan. This energy which is used by the fans forms the total energy cooling requirements which are beneficial to the building (Etheridge & Sandberg, 1996). The Variable Air Volume system has a lot of dehumidification compared to the constant volume system because the constant volume system is capable of modulating the temperature of the discharge air. The attainment of the temperature for the discharged air constitutes the cooling load of the whol e system. Within this system the blowing rate for the air is greatly varied and in the case of Variable Air Volume with a single handler for air, the serving for various multiple zones can be achieved. The flow rate associated with each multiple zone when only one handler is operational is always varied. The Variable Air system has a terminal unit and this terminal unit acts as a VAV box which controls the air flow rate for the different zones. This box operates automatically with the help of the actuator. There is a direct connection between the central or local control systems with the VAV box and the control system at times is pneumatically controlled. The use of Variable Air Volume (VAV) for many years has been able to provide quality indoor air thereby improving the quality of the surrounding environment. The quality of the surrounding air greatly affects the general environmental quality and therefore, the use of this system has been preferred in many buildings that belong to private individuals as well as companies. A lot of health benefits are attributed to indoor air quality since low quality air contains microbes that are capable of affecting the occupants of the buildings (Chadderton, 2004). A lot of prevalence has been given to the VAV system compared to CV system and this prevalence is