NEVADA C-21B AIR CONDITIONING
CONTRACTOR CERTIFICATION EXAM SCRIPT
2026 COMPREHENSIVE STUDY GUIDE WITH
SOLVED Q&A
◉ Temperature. Answer: The level of heat or heat intensity,
measured with thermometers
◉ Heat. Answer: Is the motion of molecules, and travels from a
warm substance to a cold substance
◉ Conduction. Answer: Energy travelling from one molecule to
another, involves direct contact
◉ Radiation. Answer: Passes through air and heats the first solid
object it comes in contact with
◉ Sensible Heat. Answer: Heat transfer that results in the change of
temperature of a substance
◉ Convection. Answer: Used to move heat from one location to
another, and is energy travelling through a fluid from one substance
to another
,◉ Latent Heat. Answer: Results in the change in state of a substance,
its energy is stored when a liquid turns to gas, and released when a
gas turns to a liquid.
◉ Specific Heat. Answer: The amount of heat necessary to raise the
temperature of 1lb of a substance 1 degree F.
◉ Matter. Answer: A substance that occupies space and has mass,
and is made up of atoms
◉ Mass. Answer: Is the property of matter that responds to
gravitational attraction.
◉ Density. Answer: Describes a substance's mass to volume
relationship
◉ Specific Gravity. Answer: Is a unitless number because it is the
density of a substance divided by the density of water. Water is used
as a comparison. The density of water is 62.4 lb/ft^3 which equals 1,
anything greater than 1 will sink anything less will sink.
◉ Specific Volume. Answer: Indicates the volume that each pound of
a gas occupies,when air is heated it volume increases and whens its
, cooled its volume decreases, one pound of clean dry air has a total
volume of 13.33 ft^3.
◉ Law of conservation of energy. Answer: States that energy is
neither created or destroyed but can be converted from one form to
another.
◉ One ton of refrigeration. Answer: Is the amount of heat required
to melt 1 ton of ice in a 24 hour period
◉ Temperature/Pressure Relationship. Answer: Correlates the
vapor pressure and the boiling point of water and is the basis for
controlling a system's temperature.
◉ Refrigeration Process. Answer: The boiling point of water can be
changed and controlled by controlling the vapor pressure above the
water
◉ Superheated. Answer: A liquid under pressure above its boiling
point without vaporization, is found my subtracting the evaporator
outlet temp by the evaporator saturation temp. Low superheat
means overfed coil high superheat means starved coil. should be 8-
12 degrees of overall temprature for outlet inlet should be 10-20
degrees F.
CONTRACTOR CERTIFICATION EXAM SCRIPT
2026 COMPREHENSIVE STUDY GUIDE WITH
SOLVED Q&A
◉ Temperature. Answer: The level of heat or heat intensity,
measured with thermometers
◉ Heat. Answer: Is the motion of molecules, and travels from a
warm substance to a cold substance
◉ Conduction. Answer: Energy travelling from one molecule to
another, involves direct contact
◉ Radiation. Answer: Passes through air and heats the first solid
object it comes in contact with
◉ Sensible Heat. Answer: Heat transfer that results in the change of
temperature of a substance
◉ Convection. Answer: Used to move heat from one location to
another, and is energy travelling through a fluid from one substance
to another
,◉ Latent Heat. Answer: Results in the change in state of a substance,
its energy is stored when a liquid turns to gas, and released when a
gas turns to a liquid.
◉ Specific Heat. Answer: The amount of heat necessary to raise the
temperature of 1lb of a substance 1 degree F.
◉ Matter. Answer: A substance that occupies space and has mass,
and is made up of atoms
◉ Mass. Answer: Is the property of matter that responds to
gravitational attraction.
◉ Density. Answer: Describes a substance's mass to volume
relationship
◉ Specific Gravity. Answer: Is a unitless number because it is the
density of a substance divided by the density of water. Water is used
as a comparison. The density of water is 62.4 lb/ft^3 which equals 1,
anything greater than 1 will sink anything less will sink.
◉ Specific Volume. Answer: Indicates the volume that each pound of
a gas occupies,when air is heated it volume increases and whens its
, cooled its volume decreases, one pound of clean dry air has a total
volume of 13.33 ft^3.
◉ Law of conservation of energy. Answer: States that energy is
neither created or destroyed but can be converted from one form to
another.
◉ One ton of refrigeration. Answer: Is the amount of heat required
to melt 1 ton of ice in a 24 hour period
◉ Temperature/Pressure Relationship. Answer: Correlates the
vapor pressure and the boiling point of water and is the basis for
controlling a system's temperature.
◉ Refrigeration Process. Answer: The boiling point of water can be
changed and controlled by controlling the vapor pressure above the
water
◉ Superheated. Answer: A liquid under pressure above its boiling
point without vaporization, is found my subtracting the evaporator
outlet temp by the evaporator saturation temp. Low superheat
means overfed coil high superheat means starved coil. should be 8-
12 degrees of overall temprature for outlet inlet should be 10-20
degrees F.
