Are you looking for the best air distribution products manufacturer UAE? The engineer will next choose the precise sizes, types, and configurations of the terminal units that will provide the area with comfort after calculating the building’s cooling/heating load and laying out the VAV system.
There are a number of factors to take into account when choosing single duct or fan powered terminal units, including unit capacities, sound, type, heating requirements & kind, and manufacturer.
What is VAV?
A heating, ventilation, and air conditioning (HVAC) system that provides air at variable quantities or amounts while maintaining a constant temperature is known as a VAV.
VAV HVACs are chosen over continuous airflow systems, which deliver air at varying temperatures, because they offer better temperature control, a longer parts lifespan, less noise, and more energy efficiency.
VAV systems with multiple zones are a development of VAVs. These are made up of numerous VAV terminal units or boxes that distribute air in particular regions of a big indoor environment, like an auditorium.
VAV Equipment Selection:
- Refer to Noise Criteria Value
Select a VAV box using the following NC values:
- General offices: NC 30 to NC 35.
- Open-plan-office areas: NC 40.
- Conference rooms: NC 30.
- Auditoriums: NC 30.
- Lobbies and corridors: NC 40.
- Executive offices: NC 25 to NC 30.
- Computer/equipment rooms: NC 40 to NC 45.
- Classrooms: NC 25 to NC 30.
When a VAV box has a hard duct at its intake, a lined exit plenum, and a flexible duct between its plenum and diffusers, discharge noise is rarely a problem. The maximum rating of a VAV box placed atop a typical acoustical ceiling should typically be no more than 5 NC higher than the ideal room rating to account for radiated noise. For instance, a general office with a desired NC level of 30 should not have a maximum VAV box rating of NC 35.
- Ensure Maximum Airflow matches Required Minimum Airflow Capacity
Heating airflow often has the lowest airflow. The design minimum airflow may be considerably less than the airflow offered by a vendor’s product since velocity can be challenging to measure precisely with varied airflow rates. As long as the vendor’s controls allow for 0 cfm as the lowest airflow option, this is allowed.
This essentially means that a VAV box will cycle on and off as needed to maintain the room’s temperature. Although it might not be ideal, this is frequently the only choice.
- Calculate Total Pressure Drop
Selection should be aided by total pressure decrease, not only vendor-listed static-pressure drop. Total pressure drop should not exceed 0.5 in. wc, with the exception of critical noise applications (NC 25 or below), for which static-pressure values should be input progressively lower into a selection programme until a desirable alternative is found. Following is a formula for calculating total pressure drop:
Delta TP = delta SP + delta VP
TP = total pressure drop
SP = static pressure
VP = velocity pressure
Delta TP = delta SP + [(Vin ÷ 4,005)2 – (Vout ÷ 4,005)2]
The decision about a VAV box is independent of the controls supplier. It is possible to factory-install third-party controllers on a VAV box. While it might not save money, it does shorten the time needed for procurement by delaying field installation. Coordination before building is necessary.
Tecnalco: VAV Manufacturers in UAE
Being one of the top VAV manufacturers in UAE, Tecnalco units are designed to precisely measure and control air volumes in response to zone-specific requirements for a given room temperature.
The terminals in a CAV application keep the required constant airflow constant regardless of the inlet static pressure. The terminal units in a VAV application regulate the room’s air volume in accordance with the necessary cooling load. In both new and retrofit projects, the VAV or CAV terminals can be utilised for supply or return air applications.