Air Handlers: Types, Construction, Operation, Selection, and Sizing

Question 1

What is the primary function of an air handler in an HVAC system?

Accepted Answer

To circulate and condition air throughout a building.

Answer

To generate heat for the building.

Answer

To control the humidity levels within the building.

Answer

To filter and remove pollutants from the outside air.

Question 2

Which type of air handler is most commonly used in small residential buildings?

Accepted Answer

Single-zone, forced-air furnace.

Answer

Packaged rooftop unit.

Answer

Multi-zone, variable-air-volume (VAV) system.

Answer

Central air conditioning system with a split condenser.

Question 3

What is the purpose of the blower in an air handler?

Accepted Answer

To move conditioned air throughout the building.

Answer

To regulate the temperature of the air.

Answer

To control the humidity of the air.

Answer

To filter and clean the air.

Question 4

What is the primary function of the evaporator coil in an air handler?

Accepted Answer

To absorb heat from the air and cool it down.

Answer

To remove moisture from the air.

Answer

To generate heat and warm the air.

Answer

To filter and clean the air.

Question 5

Which of the following factors is NOT a primary consideration when selecting an air handler for a building?

Accepted Answer

The color of the building's exterior.

Answer

The desired temperature and humidity levels.

Answer

The heating and cooling load of the building.

Answer

The size and layout of the building.

Question 6

How is the size of an air handler typically determined?

Accepted Answer

By calculating the total heating and cooling load of the building.

Answer

By estimating the number of occupants in the building.

Answer

By measuring the volume of the building.

Question 7

What is the primary purpose of the filter in an air handler?

Accepted Answer

To remove dust, pollen, and other airborne particles from the air.

Answer

To regulate the temperature of the air.

Answer

To control the humidity of the air.

Question 8

What type of air handler is typically used in large commercial buildings?

Accepted Answer

Multi-zone, variable-air-volume (VAV) system.

Answer

Central air conditioning system with a split condenser.

Answer

Single-zone, forced-air furnace.

Answer

Packaged rooftop unit.

Question 9

What is the benefit of using a variable-speed blower in an air handler?

Accepted Answer

Improved energy efficiency and quieter operation of the system.

Answer

Reduced maintenance requirements.

Answer

Increased airflow and cooling capacity.

Answer

Higher initial cost but lower long-term expenses.

Question 10

What is the primary function of the control system in an air handler?

Accepted Answer

To monitor and regulate the operation of air handler components.

Answer

To filter and remove pollutants from the air.

Answer

To circulate and condition air within the building.

Question 11

What is the main purpose of an air handler in an HVAC system?

Accepted Answer

To circulate and condition air within a building.

Answer

To filter and purify outdoor air.

Answer

To generate heat for the building.

Answer

To control humidity levels within the building.

Question 12

Which type of air handler is most frequently used in residential homes?

Accepted Answer

Single-zone air handler.

Answer

Variable air volume (VAV) air handler.

Answer

Multi-zone air handler.

Answer

Packaged air handler.

Question 13

Which component inside an air handler is responsible for removing dust and other particles from the air?

Accepted Answer

Air filter.

Answer

Condenser coil.

Answer

Blower motor.

Answer

Evaporator coil.

Question 14

What is the primary role of the evaporator coil in an air handler?

Accepted Answer

To absorb heat from the air passing through it.

Answer

To distribute air to different areas of the building.

Answer

To remove moisture from the air.

Answer

To transfer heat from the refrigerant to the air.

Question 15

When sizing an air handler for a specific application, what factor is the most crucial to consider?

Accepted Answer

The heating and cooling load of the building.

Answer

The brand of the air handler.

Answer

The size of the blower motor.

Answer

The type of air filter used.

Question 16

What is the main difference between a single-zone and a multi-zone air handler?

Accepted Answer

A single-zone air handler delivers air to one zone, while a multi-zone air handler can independently deliver air to multiple zones.

Answer

A single-zone air handler uses a larger blower motor than a multi-zone air handler.

Question 17

What is the primary function of the blower motor in an air handler?

Accepted Answer

To circulate air throughout the system.

Answer

To regulate airflow.

Answer

To remove moisture from the air.

Answer

To compress refrigerant.

Question 18

Which type of air filter is most commonly used in air handlers?

Accepted Answer

Fiberglass filter.

Answer

HEPA filter.

Answer

Electrostatic filter.

Answer

Carbon filter.

Question 19

How does the design of a variable air volume (VAV) air handler differ from a conventional air handler?

Accepted Answer

A VAV air handler uses a variable-speed blower motor to adjust airflow to different zones, while a conventional air handler uses a fixed-speed blower motor.

Answer

A VAV air handler uses a different type of refrigerant than a conventional air handler.

Question 20

What is the main advantage of using a packaged air handler instead of separate components?

Accepted Answer

It simplifies installation and reduces the number of components to connect.

Answer

It has a higher capacity.

Answer

It is more energy-efficient.

Question 21

Which air handler type is most suitable for a large commercial building with a high cooling load?

Accepted Answer

Central air handler

Answer

Window air conditioner

Answer

Packaged rooftop unit

Answer

Split system

Question 22

What is the primary purpose of a blower section in an air handler?

Accepted Answer

Circulating air throughout the building

Answer

Heating the air

Answer

Cooling the air

Question 23

What is the primary function of a coil within an air handler?

Accepted Answer

Transferring heat between the refrigerant and the air

Answer

Filtering the air

Answer

Controlling airflow

Question 24

When selecting an air handler for a specific application, which factor is of utmost importance?

Accepted Answer

Cooling load

Answer

Aesthetics of the unit

Answer

Noise level of the unit

Answer

Cost of the unit

Question 25

What is the primary purpose of a filter in an air handler?

Accepted Answer

Removing contaminants and impurities from the air

Answer

Controlling airflow

Answer

Cooling the air

Answer

Heating the air

Question 26

How does the air handler's fan speed impact the system's performance?

Accepted Answer

Higher fan speeds increase airflow and cooling capacity

Answer

Higher fan speeds decrease airflow and cooling capacity

Answer

Fan speed has no effect on system performance

Question 27

What is the main distinction between a single-zone and multi-zone air handler?

Accepted Answer

Single-zone systems serve one area, while multi-zone systems serve multiple areas

Answer

Multi-zone systems are more energy-efficient

Answer

Single-zone systems provide better temperature control

Question 28

Which type of air handler typically utilizes a variable-speed drive (VSD) for the blower motor?

Accepted Answer

Variable air volume (VAV) system

Answer

Packaged rooftop unit

Answer

Constant air volume (CAV) system

Answer

Window air conditioner

Question 29

What is the purpose of a damper in an air handler?

Accepted Answer

To regulate airflow to different zones or areas of the building

Answer

To filter the air

Answer

To heat the air

Question 30

How is the cooling capacity of an air handler typically measured?

Accepted Answer

Tons of refrigeration (TR)

Answer

Cubic feet per minute (CFM)

Answer

Kilowatts (kW)

Answer

British thermal units (BTU)

Question 31

An air handler is designed to condition the air by controlling which three primary factors?

Accepted Answer

Temperature, humidity, and distribution

Answer

Carbon dioxide, carbon monoxide, and volatile organic compounds

Answer

Refrigerant charge, compressor speed, and condenser fan speed

Answer

Pressure, velocity, and static

Question 32

What type of air handler is typically used in residential applications and features a direct-drive blower assembly?

Accepted Answer

Furnace/coil unit

Answer

Modular air handler

Answer

Rooftop unit (RTU)

Answer

Make-up air unit (MAU)

Question 33

Which component within an air handler is responsible for removing moisture from the air?

Accepted Answer

Evaporator coil

Answer

Blower motor

Answer

Condenser coil

Answer

Heating element

Question 34

What is the primary function of a variable-speed blower motor in an air handler?

Accepted Answer

To maintain consistent airflow and improve efficiency

Answer

To reduce the need for refrigerant

Answer

To increase the cooling capacity of the system

Question 35

When selecting an air handler, what is the most important factor to consider for proper sizing?

Accepted Answer

The required airflow in cubic feet per minute (CFM)

Answer

The manufacturer's warranty

Answer

The physical dimensions of the unit

Question 36

A technician is troubleshooting an air handler that is short cycling. What is the most likely cause of this issue?

Accepted Answer

Dirty air filter

Answer

Low refrigerant charge

Answer

Oversized ductwork

Answer

Defective thermostat

Question 37

Which type of air filter is generally considered to be the most effective at removing airborne particles?

Accepted Answer

HEPA filter

Answer

Fiberglass filter

Answer

Electrostatic filter

Question 38

What is the purpose of a condensate drain line in an air handler?

Accepted Answer

To remove excess moisture collected by the evaporator coil

Answer

To collect dust and debris from the air filter

Answer

To drain refrigerant for maintenance purposes

Question 39

What is a potential consequence of neglecting regular maintenance on an air handler?

Accepted Answer

Reduced efficiency and increased energy consumption

Answer

Extended lifespan of the compressor

Answer

Improved air quality and reduced allergens

Question 40

When installing an air handler, what is the primary reason for ensuring proper insulation of the unit and ductwork?

Accepted Answer

To prevent energy loss and condensation

Answer

To comply with fire safety regulations

Answer

To reduce noise levels during operation

Answer

To improve the aesthetics of the installation