Role of VAV box in HVAC Systems

HVAC systems are an important component of the buildings these days. Without them, the buildings look incomplete and lack an important facility of the modern era, which is centralized heating and cooling. The modern lifestyle had made people addicted to such facilities, and they even don’t prefer to be in a place which lacks this facility. That is why it becomes really important for the building owners to have these systems installed in their buildings so that they can attract the customers and don’t face any type of trouble or loss later on.

The VAV box is an essential component of the HVAC system. The word VAV stands for “Variable Air Volume”. So the name and abbreviation suggest itself, that it controls the air volume and vary it. As we already know that the heating and cooling systems are working through a proper duct channel, through which the air is being delivered in different sections of the building. The intensity of the air heating and cooling is maintained from the back-end, the control room area. But when it comes to the volume of air it is being controlled and managed through the VAV system which is installed at the openings of every duct.


We know that it is not necessary every time that different rooms will require air of a same intensity or same volume. Some rooms might be larger, whereas some might be small, so their needs may vary accordingly. So in that situation, what these boxes do is, they control the volume intensity of the air, according to the need of a particular building area. They are really effective in controlling the air volume accordingly.

They contain sensors and controllers which monitors the temperature of a particular room. They are set to an ideal constant temperature, so when the temperature reaches that level, then suddenly the volume of the air is minimized and controlled accordingly. It is made sure that a constant ideal temperature is being maintained. Afterwards, when the temperature starts exceeding beyond the certain ideal level. The volume is then increased automatically and vice versa.

That’s how a VAV box works in a HVAC system. They certainly are one of the best inventions of the present era. They have made our lives easy and comfortable. Surely, without these facilities the building, homes and shopping malls seem to be incomplete.