VAV Variable Air Volume

The video tutorial explains Variable Air Volume (VAV) systems, highlighting their energy efficiency compared to Constant Air Volume (CNV) systems. It covers the components of VAV systems, including air handling units, supply and return ducts, and VAV terminals. The tutorial details how thermostats regulate temperature by controlling dampers and discusses airflow measurement using sensors. It also explores fan-assisted VAV systems and pressure control in ductwork using variable frequency drives to optimize energy use.

What is the primary advantage of VAV systems over CAV systems?

• They allow for different temperatures in different zones.

• They are cheaper to install.

• They require less maintenance.

• They use less ductwork.

In a VAV system, what is the role of the return duct?

• To collect and remove dirty air from the rooms.

• To filter the air before it enters the rooms.

• To supply fresh air to the rooms.

• To heat the incoming air.

What component in a VAV terminal adjusts the air flow based on room temperature?

• The return grill

• The supply duct

• The thermostat

• The air filter

How does a VAV terminal determine if more cold air is needed in a room?

• By measuring the humidity levels.

• By using a thermostat to monitor room temperature.

• By checking the air pressure.

• By assessing the number of occupants in the room.

What is the purpose of the air flow sensor in a VAV system?

• To measure the temperature of the air.

• To calculate the average air velocity.

• To filter the incoming air.

• To control the speed of the fan.

What is the function of the pressure sensor in a VAV system?

• To monitor the pressure at the furthest point in the system.

• To detect air quality.

• To control the damper position.

• To measure the air temperature.

Why might a fan-assisted VAV box be used?

• To increase the air temperature.

• To maintain a constant air volume.

• To eliminate the need for a thermostat.

• To reduce the need for ductwork.

What is the role of the variable frequency drive in a VAV system?

• To measure the air flow rate.

• To filter the air entering the system.

• To control the speed of the fan motor.

• To adjust the air temperature.

How does a VAV system ensure energy efficiency?

• By using larger ducts.

• By maintaining a constant fan speed.

• By adjusting fan speed based on pressure needs.

• By using only electric reheaters.

What happens when the damper in a VAV system is fully open?

• The air is recirculated within the room.

• The air flow is stopped.

• The maximum amount of cold air enters the room.

• The room is heated.