HVAC CONTRACTOR EXAM
An instrument that measures potential differences between 2 points in an electrical
circuit is called?
A. potentiometer
B. thermistor
C. ohmeter
D. voltmeter - ANS-voltmeter
This device uses a thermal sensing bulb at the outlet of the evaporator to sense
temperature and control superheat
A. automatic expansion valve
B. thermostatic expansion valve
C. low side float
D. schraeder valve - ANS-thermostatic expansion valve
when installing a reversing valve on a heat pump, how many brazed joints should be
made?
a. 3
b. 5
c. 4
d. 2 - ANS-4
what would not be considered a misuse of a contractors license?
a. advertising under mulitple names
b. employing service technicians to work under their license
c. loaning license to more than one company
d. continue to work on an expired license - ANS-employing service technicians to work
under their license
what is used to prevent microbiological growth and help "dirty socky syndrome?
a. radiation
b. ultraviolet light
,c. electrostatic filters
d. heat rated static filters - ANS-ultraviolet light
a precisely sized drilled hole through which gas flows from the manifold to the burner is
known as what
a. spud
b. drill size
c. orifice
d. dimple - ANS-orifice
rooftop package hvac units utilize economizers for what primary purpose?
a. to exhaust extra indoor air
b. to equalize indoor/outdoor pressures
c. to allow outside air to be used for cooling in mild weather
d. to raise indoor relative humidity - ANS-to allow outside air to be used for cooling in
mild weather
what is the minimum gauge required for a 12" galvanized steel connector used to
connect a lows heat appliance?
a. .019
b. .029
c. .034
d. .2 - ANS-.029
after cutting pipes they must be reamed for what purpose?
a. to clean pipe threads
b. to smooth the end of the pipe
c. to remove burrs and chips from the inside
d. to help the threading process - ANS-to remove burrs and chips from the inside
in manual d what is the suggested friction (IWC) loss for hand dampers?
a. .01
b. .08
c. .1
d. .03 - ANS-.03
, a system with a 120 degree saturation temperature in the condenser with R-22 has a
liquid line temperature of 105 degrees. what does the temperature difference of 15
degrees represent?
a. superheat
b. wet bulb
c. subcooling
d. air temperature difference - ANS-subcooling
when a technician uses a nitrogen cylinder to pressurize a system for leak detection
what should be used for safety
a. hand valve
b. impervious gloves
c. pressure regulator
d. temperature gauge - ANS-pressure regulator
when the azeotropic blend of refrigerant condenses or evaporates at a different
temperature, it is called?
a. fractionation
b. segregation
c. purification
d. latent heat of fusion - ANS-fractionation
before brazing copper tubing what should be circulated through the tubing first
a. CO
b. refrigerant
c. oil
d nitrogen - ANS-nitrogen
a service technician should adjust the superheat setting on a TXV how often
a. never
b. when absolutely necessary
c. once a month
d. routinely - ANS-when absolutely necessary
An instrument that measures potential differences between 2 points in an electrical
circuit is called?
A. potentiometer
B. thermistor
C. ohmeter
D. voltmeter - ANS-voltmeter
This device uses a thermal sensing bulb at the outlet of the evaporator to sense
temperature and control superheat
A. automatic expansion valve
B. thermostatic expansion valve
C. low side float
D. schraeder valve - ANS-thermostatic expansion valve
when installing a reversing valve on a heat pump, how many brazed joints should be
made?
a. 3
b. 5
c. 4
d. 2 - ANS-4
what would not be considered a misuse of a contractors license?
a. advertising under mulitple names
b. employing service technicians to work under their license
c. loaning license to more than one company
d. continue to work on an expired license - ANS-employing service technicians to work
under their license
what is used to prevent microbiological growth and help "dirty socky syndrome?
a. radiation
b. ultraviolet light
,c. electrostatic filters
d. heat rated static filters - ANS-ultraviolet light
a precisely sized drilled hole through which gas flows from the manifold to the burner is
known as what
a. spud
b. drill size
c. orifice
d. dimple - ANS-orifice
rooftop package hvac units utilize economizers for what primary purpose?
a. to exhaust extra indoor air
b. to equalize indoor/outdoor pressures
c. to allow outside air to be used for cooling in mild weather
d. to raise indoor relative humidity - ANS-to allow outside air to be used for cooling in
mild weather
what is the minimum gauge required for a 12" galvanized steel connector used to
connect a lows heat appliance?
a. .019
b. .029
c. .034
d. .2 - ANS-.029
after cutting pipes they must be reamed for what purpose?
a. to clean pipe threads
b. to smooth the end of the pipe
c. to remove burrs and chips from the inside
d. to help the threading process - ANS-to remove burrs and chips from the inside
in manual d what is the suggested friction (IWC) loss for hand dampers?
a. .01
b. .08
c. .1
d. .03 - ANS-.03
, a system with a 120 degree saturation temperature in the condenser with R-22 has a
liquid line temperature of 105 degrees. what does the temperature difference of 15
degrees represent?
a. superheat
b. wet bulb
c. subcooling
d. air temperature difference - ANS-subcooling
when a technician uses a nitrogen cylinder to pressurize a system for leak detection
what should be used for safety
a. hand valve
b. impervious gloves
c. pressure regulator
d. temperature gauge - ANS-pressure regulator
when the azeotropic blend of refrigerant condenses or evaporates at a different
temperature, it is called?
a. fractionation
b. segregation
c. purification
d. latent heat of fusion - ANS-fractionation
before brazing copper tubing what should be circulated through the tubing first
a. CO
b. refrigerant
c. oil
d nitrogen - ANS-nitrogen
a service technician should adjust the superheat setting on a TXV how often
a. never
b. when absolutely necessary
c. once a month
d. routinely - ANS-when absolutely necessary
