[L9]_Air Conditioning Systems

Question 1

IND405

What is the Minimum Efficiency Reporting Value (MERV)?

[L8]

Answer 1

A measure of how well an HVAC filter captures particles.

[L8]

Question 2

IND405

True or False: High volume ventilation systems require large air-handling and duct distribution systems.

Answer 2

True.

Question 3

IND405

What is the purpose of a chiller in an HVAC system?

Answer 3

To cool water which absorbed heat from indoor space that is used then after to cool the same indoor spaces.

Question 4

IND405

List three (3) factors to consider when selecting an appropriate Air-Conditioning system for a building?

Answer 4

1. Building size and layout
2. Climate and weather conditions in the area
3. Energy efficiency goals and budget constraints

Question 5

IND405

True or False: The higher the SEER rating on an air conditioning unit, the more energy efficient it is.

Answer 5

True.

Question 6

IND405

What does VAV stand for in HVAC terminology?

Answer 6

Variable Air Volume System

Question 7

IND405

List four (4) common types of Air-Conditioning systems?

Answer 7

1. Split systems
2. Packaged systems
3. Central systems
4. Window units

Question 8

IND405

What are the five (5) most common types of HVAC filters?

Answer 8

1. Fiberglass filters
2. Pleated filters
3. Electrostatic Filters
4. HEPA Filters
5. Activated carbon filters

Question 9

IND405

What is the function of a ductless mini-split system?

Answer 9

A ductless mini-split system provides heating and cooling to individual rooms or zones without using ductwork.

Question 10

IND405

What is the purpose of an air diffuser in an HVAC system?

Answer 10

An air diffuser distributes conditioned air throughout a room or space.

Question 11

IND405

True or False: A rooftop unit (RTU) is only used for commercial buildings.

Answer 11

False. RTUs can be used for both residential and commercial buildings.

Question 12

IND405

What does SEER stand for in relation to Air-Conditioning units?

Answer 12

SEER stands for Seasonal Energy Efficiency Ratio.

Question 13

IND405

What is the function of a humidifier in an HVAC system?

Answer 13

A humidifier adds moisture to dry indoor air during winter months when heating systems can cause low humidity levels.

Question 14

IND405

Name the four (4) most common refrigerants which have been used in HVAC systems.

Answer 14

1. R-22 (Freon)
2. R-410A (Puron)
3. R-134a
4. R32

Question 15

IND405

What is the purpose of a compressor in an HVAC system?

Answer 15

A compressor compresses refrigerant gas to increase its temperature and pressure, allowing it to absorb heat from indoor spaces.

Question 16

IND405

What is the difference between a single-stage and a two-stage furnace?

Answer 16

A single-stage furnace has only one heating output level, while a two-stage furnace has two heating output levels for greater efficiency.

Question 17

IND405

True or False: A geothermal heat pump uses the earth’s natural heat to provide heating and cooling.

Answer 17

True.

Question 18

IND405

Describe the function of an evaporator coil in an HVAC system?

Answer 18

An evaporator coil absorbs heat from indoor air as refrigerant flows through it, cooling the air before it is distributed throughout a space.

Question 19

IND405

List the four (4) common types of ductwork used in HVAC systems?

Answer 19

1. Galvanized sheet metal
2. Fiberglass
3. Flexible
4. Stainless Steel

Question 20

IND405

What is the function of a condenser coil in an HVAC system?

Answer 20

A condenser coil releases heat absorbed from indoor spaces into outdoor air as refrigerant flows through it.

Question 21

IND405

List three (3) common types of commercial HVAC systems.

Answer 21

1. Packaged Rooftop Units (RTUs)
2. Variable Refrigerant Flow (VRF) systems
3. Chiller Systems

Question 22

IND405

Explain the purpose of zoning in an HVAC system?

Answer 22

Zoning allows for different areas or rooms within a building to have individual temperature control for greater comfort and energy efficiency.

Question 23

IND405

What is the difference between a humidistat and a thermostat in an HVAC system?

Answer 23

A humidistat measures and controls the humidity level in a space, while a thermostat measures and controls the temperature.

Question 24

IND405

What are common types of commercial refrigeration systems for food storage?

Answer 24

1. Walk-in coolers/freezers
2. Reach-in refrigerators/freezers
3. Display refrigeration cases

Question 25

# IND405 What is the **function** of a **damper** in an HVAC system?

Answer 25

A damper regulates airflow by opening or closing to control the amount of conditioned air that enters a space.

Question 26

# IND405 What is the **purpose** of a **backup heating source** in an HVAC system?

Answer 26

A backup heating source provides heat when the primary heating source (such as a heat pump) cannot keep up with demand due to extreme temperatures or other factors.

Question 27

# IND405 What is the **function** of a **reversing valve** in an HVAC system?

Answer 27

A reversing valve switches the direction that refrigerant flows through an HVAC system to allow for both heating and cooling modes.

Question 28

# IND405 What is the **function** of a **filter drier** in an HVAC system?

Answer 28

A filter drier removes moisture and contaminants from refrigerant to prevent damage to other components in the HVAC system.

Question 29

# IND405 **True** or **False**: A heat recovery ventilator (HRV) can improve indoor air quality by exchanging stale indoor air with fresh outdoor air.

Answer 29

True.

Question 30

# IND405 What is the **purpose** of **insulation** in an HVAC system?

Answer 30

Insulation helps to prevent heat loss or gain through ductwork or other components, improving energy efficiency.

Question 31

# IND405 What is the **function** of a **pressure switch** in an HVAC system?

Answer 31

A pressure switch monitors pressure levels within an HVAC system and can shut off the system if levels become too high or too low.

Question 32

# IND405 List **four (4) common types of commercial boilers**.

Answer 32

1. Firetube Boilers 2. Watertube Boilers 3. Condensing Boilers 4. Electric Boilers

Question 33

# IND405 What is the **purpose** of a **UV air purifier** in an HVAC system?

Answer 33

A UV air purifier uses ultraviolet light to kill bacteria, viruses, and other microorganisms in indoor air for improved indoor air quality.

Question 34

# IND405 List **three (3) common types of commercial humidifiers**.

Answer 34

1. Steam humidifiers 2. Evaporative humidifiers 3. Ultrasonic humidifiers

Question 35

# IND405 List **three (3) common types of commercial dehumidifiers**.

Answer 35

1. Refrigerant dehumidifiers 2. Desiccant dehumidifiers 3. Ventilating dehumidifiers

Question 36

# IND405 How does a **geothermal HVAC system work**, and **what** are some **benefits** of using this type of system for heating and cooling?

Answer 36

The ground's constant temperature powers geothermal HVAC systems. Underground pipelines transfer ground heat in winter and return it in summer. It uses no fossil fuels or greenhouse emissions and works effectively. Geothermal HVAC systems reduce energy expenditures, carbon emissions, and indoor air pollution.

Question 37

# IND405 What is the **role** of **air balancing** in an HVAC system, and how can it improve **energy efficiency** and **indoor air quality**?

Answer 37

Air balancing adjusts an HVAC system's airflow to heat or cool each room properly. This saves energy in locations that don't need as much heating or cooling and improves air quality by allowing in adequate air. Dampers, variable-speed fans, and filtering devices balance air.

Question 38

# IND405 What are some **common maintenance tasks** for an HVAC system, and **how often should they be performed**? ## Footnote [L8]

Answer 38

Check the air filters, coils, refrigerant level, ducting, lubricants, and electrical connections. These chores improve efficiency. Usage, environment, and device age dictate maintenance frequency. Change air filters monthly. Depending on usage, coils should be cleaned once or twice a year. Licensed technicians should check refrigerant levels annually. Check the ductwork every five to ten years or as needed for repairs or improvements. ## Footnote [L8]

Question 39

# IND405 What is a **demand-controlled ventilation (DCV) system**, and how can it improve indoor air quality and energy efficiency in commercial buildings? ## Footnote [L8]

Answer 39

DCV systems regulate outside air intake depending on consumption or IAQ data. Sensors adjust airflow depending on CO2 and room occupancy. DCV systems save energy and clean corporate buildings which provide fresh air as required, improving IAQ. ## Footnote [L8]