Types of Furnaces: A Comprehensive Guide for HVAC Technicians

Question 1

Which type of furnace uses a blower to distribute warm air in a room?

Accepted Answer

Forced-air furnace

Answer

Gravity furnace

Answer

Radiant furnace

Answer

Steam furnace

Question 2

Which of the following is NOT a type of furnace?

Accepted Answer

Wood stove

Answer

Gas furnace

Answer

Oil furnace

Answer

Electric furnace

Question 3

In a gas furnace, which component initiates the combustion process?

Accepted Answer

Burner assembly

Answer

Heat exchanger

Answer

Blower motor

Answer

Control board

Question 4

Which type of furnace utilizes heating oil as its fuel source?

Accepted Answer

Oil furnace

Answer

Natural gas furnace

Answer

Propane furnace

Answer

Electric furnace

Question 5

In an electric furnace, which component is responsible for converting electrical energy into heat?

Accepted Answer

Heating element

Answer

Burner

Answer

Heat exchanger

Answer

Blower

Question 6

What is the primary function of a draft inducer in a furnace?

Accepted Answer

To draw combustion air into the furnace

Answer

To expel exhaust gases from the furnace

Answer

To regulate the temperature of the furnace

Answer

To ignite the fuel in the burner

Question 7

Which type of furnace is renowned for its energy efficiency and reduced emissions?

Accepted Answer

Condensing furnace

Answer

Non-condensing furnace

Answer

Oil furnace

Answer

Electric furnace

Question 8

What is the purpose of a humidifier integrated into a furnace system?

Accepted Answer

To increase the moisture content of the air

Answer

To decrease the moisture content of the air

Answer

To regulate the temperature of the furnace

Answer

To clean the air passing through the furnace

Question 9

When troubleshooting a furnace that fails to ignite, which step should be considered first?

Accepted Answer

Checking the flame sensor

Answer

Replacing the control board

Answer

Rewiring the thermostat

Answer

Adjusting the gas pressure

Question 10

Identify the central component that burns fuel in an oil furnace.

Accepted Answer

Burner

Answer

Heat exchanger

Answer

Igniter

Answer

Thermostat

Question 11

In the context of furnaces, what does the acronym AFUE represent?

Accepted Answer

Annual Fuel Utilization Efficiency

Answer

Airflow Uniformity Efficiency

Answer

American Furnace Uniformity Efficiency

Answer

Annual Fuel Utilization Energy

Question 12

What is the primary function of a plenum in a furnace system?

Accepted Answer

Distributing heated air

Answer

Expelling combustion gases

Answer

Housing furnace components

Answer

Regulating air flow

Question 13

Which of the following is NOT a common type of furnace used in residential applications?

Accepted Answer

Wood-burning stove

Answer

Gas furnace

Answer

Oil furnace

Answer

Electric furnace

Question 14

Which type of furnace operates by combusting natural gas to generate heat?

Accepted Answer

Gas furnace

Answer

Electric furnace

Answer

Oil furnace

Answer

Propane furnace

Question 15

Which component of an oil furnace is primarily responsible for igniting the fuel?

Accepted Answer

Igniter

Answer

Blower motor

Answer

Heat exchanger

Answer

Flue pipe

Question 16

What is the primary function of the heat exchanger in an electric furnace?

Accepted Answer

To transfer heat to the air

Answer

To ignite the fuel

Answer

To filter the air

Answer

To circulate the air

Question 17

What type of fuel is primarily used in oil furnaces?

Accepted Answer

Heating oil

Answer

Natural gas

Answer

Propane

Answer

Diesel

Question 18

What is the term for the process of removing soot and other deposits from the heat exchanger of a furnace?

Accepted Answer

Cleaning

Answer

Maintenance

Answer

Inspection

Answer

Tune-up

Question 19

In an oil furnace, what is the primary fuel source?

Accepted Answer

Kerosene

Answer

Natural gas

Answer

Propane

Answer

Electricity

Question 20

Within a furnace, which component initiates fuel ignition?

Accepted Answer

Burner

Answer

Heat exchanger

Answer

Blower

Answer

Thermostat

Question 21

In a gas furnace, what is the purpose of the heat exchanger?

Accepted Answer

Transferring heat from combustion to air

Answer

Igniting the fuel

Answer

Filtering air

Answer

Regulating airflow

Question 22

Which issue is commonly associated with oil furnaces?

Accepted Answer

Soot buildup

Answer

Gas leaks

Answer

Electrical malfunctions

Answer

Filter clogging

Question 23

For preventing carbon monoxide poisoning, what safety feature is typically installed in furnaces?

Accepted Answer

Carbon monoxide sensor

Answer

Smoke detector

Answer

Flame sensor

Answer

Oxygen sensor

Question 24

What is the main purpose of a thermostat in a furnace system?

Accepted Answer

Regulating indoor temperature

Answer

Igniting fuel

Answer

Circulating air

Answer

Filtering air

Question 25

In a gas furnace, which component initiates the ignition of gas to begin combustion?

Accepted Answer

Igniter

Answer

Burner

Answer

Heat exchanger

Answer

Blower

Question 26

Which furnace type is commonly found in residential settings and does not require an external fuel supply line?

Accepted Answer

Electric furnace

Answer

Gas furnace

Answer

Oil furnace

Answer

Propane furnace

Question 27

Which furnace component plays a crucial role in transferring heat to the circulating air?

Accepted Answer

Heat exchanger

Answer

Burner

Answer

Blower

Answer

Thermostat

Question 28

What is the primary safety feature in an oil furnace that prevents ignition without detecting a flame?

Accepted Answer

Flame sensor

Answer

Thermostat

Answer

Limit switch

Answer

Pressure switch

Question 29

Which furnace type stands out for its high efficiency and incorporates a heat pump?

Accepted Answer

Hybrid furnace

Answer

Gas furnace

Answer

Oil furnace

Answer

Electric furnace

Question 30

Which component is typically NOT found in a furnace system?

Accepted Answer

Evaporator coil

Answer

Blower

Answer

Heat exchanger

Answer

Air filter

Question 31

Which type of furnace is known for its high energy efficiency?

Accepted Answer

Condensing furnace

Answer

Oil furnace

Answer

Electric resistance furnace

Question 32

What is the primary fuel used in an oil furnace?

Accepted Answer

Kerosene

Answer

Natural gas

Answer

Propane

Answer

Electricity

Question 33

Which component of a gas furnace is responsible for igniting the fuel?

Accepted Answer

Igniter

Answer

Heat exchanger

Answer

Burner

Answer

Blower motor

Question 34

What is the purpose of a draft inducer in a furnace?

Accepted Answer

To create negative pressure in the combustion chamber

Answer

To circulate heated air throughout the building

Answer

To ignite the fuel

Question 35

Which type of furnace does not require a flue for exhaust gases?

Accepted Answer

Electric furnace

Answer

Condensing furnace

Answer

Oil furnace

Answer

Gas furnace

Question 36

What is the main disadvantage of a gravity furnace?

Accepted Answer

Poor energy efficiency

Answer

High maintenance costs

Answer

Difficult to control temperature

Answer

Requires a flue

Question 37

Which type of furnace can adjust its output to match changes in heating demand?

Accepted Answer

Modulating furnace

Answer

Single-stage furnace

Answer

Gravity furnace

Answer

Two-stage furnace

Question 38

What is the primary function of a blower motor in a furnace?

Accepted Answer

To circulate heated air through the ductwork

Answer

To ignite the fuel

Answer

To provide combustion air to the burner

Answer

To control the temperature of the furnace

Question 39

Which type of furnace utilizes a refrigerant to transfer heat?

Accepted Answer

Heat pump

Answer

Gas furnace

Answer

Electric resistance furnace

Answer

Oil furnace

Question 40

Which type of furnace generally has the highest energy efficiency rating (AFUE)?

Accepted Answer

Gas furnace

Answer

Wood-burning stove

Answer

Oil furnace

Answer

Electric furnace

Question 41

What type of furnace uses a combustion chamber to burn fuel and heat air, which is then circulated through the house using a blower?

Accepted Answer

Forced-air furnace

Answer

Radiant furnace

Answer

Convection furnace

Answer

Hydronic furnace

Question 42

Which component of a forced-air furnace is responsible for moving heated air through the ductwork and into the living spaces?

Accepted Answer

Blower motor

Answer

Flue pipe

Answer

Burner

Answer

Heat exchanger

Question 43

The primary difference between a gas furnace and an oil furnace is:

Accepted Answer

The type of fuel they use

Answer

The cost of installation

Answer

The size of the furnace

Answer

The efficiency of the furnace

Question 44

Which type of furnace is typically known for its quiet operation and minimal maintenance requirements?

Accepted Answer

Electric furnace

Answer

Wood-burning stove

Answer

Gas furnace

Answer

Oil furnace

Question 45

What safety feature is crucial for preventing carbon monoxide buildup from a furnace with combustion?

Accepted Answer

Carbon monoxide detector

Answer

Smoke detector

Answer

Fire extinguisher

Answer

Heat sensor

Question 46

A common problem associated with gas furnaces is:

Accepted Answer

A gas leak in the supply line

Answer

Clogged filter

Answer

Overheating

Answer

Electrical failure

Question 47

What type of maintenance is crucial for maintaining the optimal performance of an oil furnace?

Accepted Answer

Annual cleaning and tune-up by a qualified technician

Answer

Monthly filter replacement

Answer

Quarterly inspection

Answer

No regular maintenance required

Question 48

Which of the following factors is most important when determining the appropriate size for a furnace?

Accepted Answer

The square footage of the home

Answer

The height of the ceilings

Answer

The number of windows in the home

Answer

The type of insulation used

Question 49

What is the primary function of a flue pipe in a furnace?

Accepted Answer

To safely vent combustion gases and byproducts outside the home

Answer

To regulate the temperature of the furnace

Answer

To filter the air before it enters the furnace

Answer

To supply oxygen to the burner

Question 50

Which type of furnace is known for its high efficiency and low operating costs?

Accepted Answer

High-efficiency gas furnace

Answer

Electric furnace

Answer

Standard gas furnace

Answer

Oil furnace

Question 51

A furnace with a blower motor that circulates heated air through ductwork is classified as a(n):

Accepted Answer

Forced-air furnace

Answer

Boiler

Answer

Heat pump

Answer

Gravity furnace

Question 52

Which component in a gas furnace is responsible for igniting the gas and initiating the combustion process?

Accepted Answer

Ignitor

Answer

Blower motor

Answer

Heat exchanger

Answer

Thermostat

Question 53

An oil furnace uses a(n) ______ to atomize fuel oil before it is burned.

Accepted Answer

Oil burner

Answer

Ignitor

Answer

Draft inducer motor

Answer

Air filter

Question 54

Which type of furnace is considered the most environmentally friendly option due to its lack of combustion emissions?

Accepted Answer

Electric furnace

Answer

Gas furnace

Answer

Oil furnace

Answer

Heat pump

Question 55

A furnace's ______ is responsible for transferring heat from the combustion process to the air that is circulated throughout the house.

Accepted Answer

Heat exchanger

Answer

Blower motor

Answer

Thermostat

Answer

Burner

Question 56

What is the primary purpose of a draft inducer motor in a gas furnace?

Accepted Answer

To vent combustion gases safely and efficiently

Answer

To control the flow of fuel gas

Answer

To circulate heated air throughout the house

Answer

To ignite the gas burner

Question 57

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

Accepted Answer

Two-stage furnaces offer more precise temperature control by adjusting the burner output.

Answer

Single-stage furnaces are more energy-efficient.

Answer

Two-stage furnaces are typically louder than single-stage furnaces.

Question 58

Which type of furnace is best suited for a home with a limited amount of space for ductwork?

Accepted Answer

Electric furnace

Answer

Oil furnace

Answer

Gas furnace

Answer

Heat pump

Question 59

Regular maintenance, such as cleaning the heat exchanger and inspecting the burner assembly, is essential for ensuring the safe and efficient operation of a(n):

Accepted Answer

Gas furnace

Answer

Heat pump

Answer

All types of furnaces

Answer

Electric furnace