HVAC Ductwork: Types, Design, and Installation Techniques

Question 1

Which of the following is commonly used for the fabrication of flexible air ducts?

Accepted Answer

Flexible plastic

Answer

Sheet metal

Answer

Fiberglass

Answer

Rigid plastic

Question 2

What is the primary purpose of using a duct liner in HVAC systems?

Accepted Answer

To reduce noise levels

Answer

To improve airflow efficiency

Answer

To prevent condensation

Answer

To provide structural support

Question 3

What is the main purpose of applying a duct sealant?

Accepted Answer

To prevent air leaks

Answer

To improve thermal insulation

Answer

To reduce duct noise

Answer

To enhance duct strength

Question 4

Which type of air distribution system utilizes a central fan to distribute air through ducts?

Accepted Answer

Forced-air system

Answer

Gravity system

Answer

Radiant system

Answer

Convection system

Question 5

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

Accepted Answer

To regulate airflow

Answer

To prevent backdraft

Answer

To control temperature

Answer

To filter air

Question 6

When manufacturing round ductwork, which material is predominantly used?

Accepted Answer

Galvanized steel

Answer

Aluminum

Answer

PVC

Answer

Fiberglass

Question 7

Which material is not commonly used in the fabrication of HVAC ductwork?

Accepted Answer

Concrete

Answer

Galvanized steel

Answer

Aluminum

Answer

Fiberglass

Question 8

Which device is used to measure the airflow rate within an HVAC ductwork system?

Accepted Answer

Anemometer

Answer

Manometer

Answer

Voltmeter

Answer

Ohmmeter

Question 9

Which type of ductwork system is characterized by high velocity and relatively smaller duct size?

Accepted Answer

High-velocity ductwork

Answer

Conventional ductwork

Answer

Underground ductwork

Answer

Plenum ductwork

Question 10

In HVAC ductwork fabrication, which type of joint is the most commonly used?

Accepted Answer

Slip joint

Answer

Soldered joint

Answer

Flanged joint

Answer

Riveted joint

Question 11

What is the main function of a balancing damper in an HVAC ductwork system?

Accepted Answer

To ensure balanced airflow distribution

Answer

To reduce noise levels

Answer

To prevent backdraft

Answer

To insulate the ductwork

Question 12

The primary purpose of HVAC ductwork is to:

Accepted Answer

Distribute conditioned air throughout a building

Answer

Collect and remove dust from the air

Answer

Provide structural support for the HVAC system

Answer

Reduce noise and vibration from the HVAC system

Question 13

In residential HVAC systems, the most commonly used material for ductwork is:

Accepted Answer

Galvanized steel

Answer

Flexible aluminum

Answer

PVC

Answer

Copper

Question 14

Which type of ductwork is typically used for low-pressure air distribution systems?

Accepted Answer

Flexible ductwork

Answer

Rigid ductwork

Answer

Spiral ductwork

Answer

Oval ductwork

Question 15

The primary factor that determines the size of HVAC ductwork is:

Accepted Answer

Required airflow rate

Answer

Size of the building

Answer

Type of HVAC system installed

Answer

Noise level produced by the HVAC system

Question 16

The purpose of using vibration isolators in HVAC ductwork systems is to:

Accepted Answer

Reduce noise transmission

Answer

Prevent damage to ductwork

Answer

Improve airflow efficiency

Answer

Extend the lifespan of the HVAC system

Question 17

The device used to measure airflow in HVAC ductwork is an:

Accepted Answer

Anemometer

Answer

Manometer

Answer

Thermometer

Answer

Hygrometer

Question 18

What are the typical maintenance and troubleshooting procedures for HVAC ductwork?

Accepted Answer

Cleaning, leak detection, and airflow measurement

Answer

Insulation replacement and duct sealing

Answer

Thermostat calibration and filter changing

Answer

Electrical wiring inspection and voltage testing

Question 19

What is the primary purpose of HVAC ductwork in a heating and cooling system?

Accepted Answer

To distribute conditioned air throughout a building

Answer

To maintain a desired indoor temperature

Answer

To regulate the flow of air in the HVAC system

Answer

To reduce noise from the HVAC system

Question 20

What is the main purpose of using dampers in HVAC ductwork systems?

Accepted Answer

To control the flow of air in different parts of the system

Answer

To balance air pressure within the ductwork

Answer

To adjust the temperature of the air flowing through the ducts

Answer

To filter out contaminants from the air

Question 21

According to safety regulations, what is the recommended minimum clearance between HVAC ductwork and combustible materials to prevent fire hazards?

Accepted Answer

12 inches

Answer

6 inches

Answer

18 inches

Answer

24 inches

Question 22

Which instrument is used to measure the velocity of airflow in HVAC ductwork?

Accepted Answer

Anemometer

Answer

Manometer

Answer

Thermometer

Answer

Psychrometer

Question 23

Which type of ductwork is best suited for applications requiring high-pressure air handling?

Accepted Answer

Stainless steel

Answer

Galvanized steel

Answer

Aluminum

Answer

Fiberglass

Question 24

During HVAC ductwork installation, what is the main reason for using sealants and insulation?

Accepted Answer

To prevent air leaks and reduce energy loss

Answer

To enhance the visual appeal of the ductwork

Answer

To reduce noise caused by airflow

Answer

To increase airflow volume in the ductwork

Question 25

Which ductwork material is flexible and easy to install, making it ideal for short runs and flexible connections?

Accepted Answer

Flexible ductwork

Answer

Sheet metal

Answer

Rigid fiberglass

Question 26

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

Accepted Answer

To distribute air to multiple rooms or spaces

Answer

To mix air from different sources

Answer

To reduce noise and vibration

Answer

To filter pollutants from the air

Question 27

Which tool is specifically designed for cutting and shaping sheet metal used in ductwork fabrication?

Accepted Answer

Snips

Answer

Circular saw

Answer

Miter saw

Answer

Jigsaw

Question 28

In designing HVAC ductwork, which factor is paramount?

Accepted Answer

Airflow volume

Answer

Material expense

Answer

Visual appeal

Question 29

How do turning vanes and diverters contribute to optimizing airflow distribution in HVAC ductwork systems?

Accepted Answer

Turning vanes reduce pressure drops and promote even airflow.

Accepted Answer

Diverters adjust airflow volume to balance pressure in duct branches.

Answer

Turning vanes and diverters are only used in large HVAC systems.

Answer

Accessories have no significant impact on HVAC ductwork efficiency.

Question 30

In the context of HVAC ductwork design, which factor is paramount for ensuring environmental sustainability?

Accepted Answer

Energy efficiency and reduction of operational carbon footprint

Answer

Flammability of materials and its impact on fire safety

Answer

Availability and cost of transporting materials

Answer

Aesthetics and visual appeal of the ductwork system

Question 31

Which type of ductwork is fabricated from thin metal sheets, commonly utilized for residential applications?

Accepted Answer

Sheet metal ductwork

Answer

Plastic ductwork

Answer

Flexible ductwork

Answer

Fiberboard ductwork

Question 32

What is the primary purpose of a duct liner?

Accepted Answer

To mitigate noise and enhance air quality

Answer

To amplify airflow

Answer

To prevent condensation

Answer

To provide support for the ductwork

Question 33

Which of the following factors does NOT influence ductwork sizing calculations?

Accepted Answer

Outdoor temperature

Answer

Friction loss

Answer

Duct length

Answer

Airflow rate

Question 34

What is the primary function of a damper within an HVAC ductwork system?

Accepted Answer

To regulate airflow and its distribution

Answer

To prevent condensation formation

Answer

To provide structural support for the ductwork

Answer

To reduce noise levels

Question 35

Why is proper ductwork installation crucial in HVAC systems?

Accepted Answer

To ensure optimal performance, efficiency, and the desired indoor environment

Answer

To minimize maintenance expenses

Answer

To enhance the visual appeal of the building

Question 36

Which type of ductwork is characterized by its flexibility and ease of installation, making it ideal for tight spaces or irregular duct routes?

Accepted Answer

Flexible duct

Answer

Rectangular duct

Answer

Round duct

Answer

Oval duct

Question 37

Which type of duct joint is specifically designed for connecting rectangular ducts at right angles, providing a secure and airtight seal?

Accepted Answer

90-degree elbow

Answer

Transition joint

Answer

Tee joint

Answer

Slip joint

Question 38

What is the primary purpose of a turning vane installed inside an HVAC duct, particularly around bends?

Accepted Answer

To improve airflow efficiency by guiding the air smoothly around bends, minimizing energy loss and pressure drop.

Answer

To prevent the formation of condensation by promoting even airflow and reducing moisture buildup.

Answer

To increase the structural integrity of the ductwork by providing additional support and reinforcing the duct walls.

Question 39

What is the primary purpose of a duct access panel installed in HVAC ductwork systems?

Accepted Answer

To provide easy access for inspection, cleaning, and maintenance, ensuring the proper functioning and longevity of the system.

Answer

To improve airflow efficiency by reducing pressure drop and optimizing air distribution.

Answer

To reduce noise levels by absorbing sound waves and minimizing vibration.

Question 40

When designing HVAC ductwork systems, which factor is of paramount importance to consider, as it directly impacts the system's performance and efficiency?

Accepted Answer

Airflow capacity and pressure drop

Answer

Material cost

Answer

Ease of installation

Answer

Aesthetics

Question 41

What is the primary advantage of utilizing a variable air volume (VAV) system in HVAC applications, enabling efficient and effective climate control?

Accepted Answer

Energy efficiency and zone control, allowing for precise temperature regulation in different areas of a building while minimizing energy consumption.

Answer

Reduced noise levels by utilizing silencers and sound-absorbing materials.

Answer

Increased system capacity by allowing for greater airflow rates when needed.

Answer

Improved indoor air quality by enhancing air circulation and reducing the buildup of stale air.

Question 42

In residential applications, which type of ductwork is most commonly used?

Accepted Answer

Round flex duct

Answer

Oval duct

Answer

Spiral pipe

Answer

Rectangular sheet metal duct

Question 43

In determining the appropriate size of a duct, which airflow measurement is utilized?

Accepted Answer

Cubic feet per minute (CFM)

Answer

British Thermal Units (BTUs)

Answer

Inches of water (in. wg)

Answer

Feet per minute (FPM)

Question 44

When connecting round flex ducts, which type of joint is typically used?

Accepted Answer

Slip-and-drive connector

Answer

Sheet metal screw

Answer

Pop rivet

Answer

Soldered joint

Question 45

What is the intended purpose of a duct sealant?

Accepted Answer

To prevent air leakage and improve the efficiency of the system

Answer

To serve as a vapor barrier and prevent moisture penetration

Answer

To insulate the duct and minimize heat transfer

Answer

To provide structural support and reinforce the duct

Question 46

Within a duct system, what type of airflow pattern is generally preferred?

Accepted Answer

Laminar

Answer

Eddy

Answer

Turbulent

Answer

Vortical

Question 47

In a duct system, what is the primary function of a damper?

Accepted Answer

To regulate and control the flow of air

Answer

To insulate the duct and minimize heat loss

Answer

To provide structural support to the duct

Question 48

What is the primary function of a transition fitting in a ductwork system?

Accepted Answer

Connecting ducts of different sizes or shapes.

Answer

Reducing noise levels in the system.

Answer

Facilitating air balancing.

Answer

Improving airflow efficiency.

Question 49

What is the recommended maximum length-to-diameter ratio for round ductwork to maintain efficient airflow?

Accepted Answer

10:1

Answer

5:1

Answer

20:1

Answer

15:1

Question 50

Which type of sealant is commonly used to seal joints and seams in ductwork systems?

Accepted Answer

Mastic sealant

Answer

Caulk

Answer

Epoxy

Answer

Tape

Question 51

What is the main purpose of using flex connectors in ductwork systems?

Accepted Answer

To reduce vibration and noise transmission.

Answer

To improve airflow efficiency.

Answer

To facilitate duct cleaning.

Answer

To prevent condensation formation.

Question 52

Which type of ductwork is suitable for use in applications involving high temperatures?

Accepted Answer

Double-wall ductwork

Answer

Flexible ductwork

Answer

Oval ductwork

Answer

Single-wall ductwork

Question 53

What is the primary function of a damper in a ductwork system?

Accepted Answer

To control airflow

Answer

To prevent backdraft

Answer

To reduce noise levels

Answer

To improve indoor air quality