HVAC Duct Fittings and Installation

What is the primary function of a hand damper in a takeoff fitting?

• To seal the connection between the takeoff and the main duct.

• To adjust the air velocity and balance air distribution in a room.

• To prevent backdrafts in the ductwork.

• To provide an access point for cleaning the ductwork.

Which fitting is commonly used to transition between different duct sizes in an HVAC system?

• Takeoff

• Reducer

• Hand damper

• Canvas connector

Which type of prefabricated duct fitting is typically used inside a wall cavity where space is limited?

• Round pipe

• Oval pipe

• Flexible duct

• Square duct

What is the main advantage of using flexible ductwork in residential HVAC systems?

• It provides better insulation than metal ductwork.

• It is easier to install around obstacles and tight spaces.

• It is more resistant to corrosion.

• It increases the airflow velocity.

For what common application is a Boston elbow primarily used?

• To connect supply ducts to a main trunk line.

• To facilitate a 90-degree turn in a supply duct.

• To create a transition between different duct sizes.

• To serve as a return drop, often incorporating a filter.

Which type of duct fitting is most effective for minimizing airflow resistance at a sharp turn?

• Turning vane

• Reducer

• Boston elbow

• Canvas connector

Which component is commonly used to allow access for cleaning and inspection inside ductwork?

• Hand damper

• Reducer

• Offset

• Access door

What is the main reason for using mastic when sealing duct joints?

• To provide a flexible, airtight seal that prevents air leakage.

• To add structural strength to the ductwork.

• To insulate the duct from temperature changes.

• To make the ductwork easier to paint.

Why is duct sealing considered essential in HVAC systems?

• To enhance the aesthetic appeal of the ductwork.

• To prevent the loss of heating or cooling capacity to un-conditioned spaces.

• To make the ductwork easier to clean and maintain.

• To reduce noise levels within the duct system.

What is the primary function of a plenum in an HVAC system?

• To connect two separate supply ducts.

• To change the dimensions of the ductwork.

• To serve as the first piece of ductwork attached to a furnace or air handler.

• To navigate around obstructions in the duct path.