HVAC S.T.A.R Questions With Correct
Answers
Face and bypass dampers should be adjusted to provide: Tight shut off to reduce the
possibility of overcooling or overheating
With belt driven equipment, alignment of the motor and driven equipment pulleys Is
accomplished using a string or straight edge.
To assist consumers in making an informed choice when purchasing unitary air conditioning
equipment, the efficiency of such units is expressed as Energy Efficiency Ratio (EER or SEER)
the units of which are: Btuh/watt
Firestats located in the air stream of air handling units: A. Partially Correct: Are required
in both the supply and return air streams
B. Partially Correct: Should be the manual reset type
C. Partially Correct: Should be nonadjustable
A sleeve bearing would typically be used in a motor that: Operates with a light load and
where noise is a factor.
A bearing used on the bottom of a motor where the shaft is positioned vertically is called a
____________ bearing. Thrust
,To produce electromagnetism, relative motion is required between a magnetic field and a/an:
Conductor
Materials which do not allow their electrons to spin out of orbit easily are called:
Insulators
A battery is an example of a/an ____________ source. Direct current
"Current flowing through a conductor in one direction for a split second, then in the opposite
direction for a split second" would be a good definition of: Alternating current
If a pressure gauge reads five psig at sea level elevation, the corresponding absolute pressure is
___________ psia. Fractional
The portion of the electromagnetic spectrum to which solar collectors respond is _____ and near-
infrared radiation. Visible light
During winter, ________. Daylight is shorter and the Northern Hemisphere is angled
away from the sun
Unless equipped with OSHA or Canadian Standards Association (CSA) approved ground-fault
circuit interrupters, portable electric lighting used in wet and-or other conductive locations as, for
example, drums, tanks and vessels, shall be operated at ______ volts or less. 12
, Receivers are usually required in systems having: Evaporative condensers
An important feature of a refrigerant receiver, in the case where the liquid line to the evaporator
comes out of the top of the receiver, is a: Dip tube
A pressure regulator is constructed so that a rise in ____________ steam pressure reduces off the
inlet flow of supply steam. Downstream
A vacuum breaker is used to avoid which of the following Negative gauge pressure
Lock-out relays are used in air conditioning systems to: Prevent compressor short-cycling
When measuring the winding resistance of a split-phase compressor motor, the smallest value
will be measured between the: The run terminal and the common terminal
Cavitation in a pump pumping hot water: A. Partial Correct: Makes a pump noisy
B. Partial Correct: Is the result of water boiling into the steam
C. Partial Correct: Is the result of insufficient NPSH
The amount of heat removed to lower the temperature of 15 lbs. of water from 48 degrees F to 39
degrees F is: 135 Btu.
Heat = Weight (lbs.) x Specific Heat (Btu/lb. per degree) F x Temperature (degrees F) = 15 x1
(48-39) degrees F = 15 x 1 x 9 = 135 Btu
Answers
Face and bypass dampers should be adjusted to provide: Tight shut off to reduce the
possibility of overcooling or overheating
With belt driven equipment, alignment of the motor and driven equipment pulleys Is
accomplished using a string or straight edge.
To assist consumers in making an informed choice when purchasing unitary air conditioning
equipment, the efficiency of such units is expressed as Energy Efficiency Ratio (EER or SEER)
the units of which are: Btuh/watt
Firestats located in the air stream of air handling units: A. Partially Correct: Are required
in both the supply and return air streams
B. Partially Correct: Should be the manual reset type
C. Partially Correct: Should be nonadjustable
A sleeve bearing would typically be used in a motor that: Operates with a light load and
where noise is a factor.
A bearing used on the bottom of a motor where the shaft is positioned vertically is called a
____________ bearing. Thrust
,To produce electromagnetism, relative motion is required between a magnetic field and a/an:
Conductor
Materials which do not allow their electrons to spin out of orbit easily are called:
Insulators
A battery is an example of a/an ____________ source. Direct current
"Current flowing through a conductor in one direction for a split second, then in the opposite
direction for a split second" would be a good definition of: Alternating current
If a pressure gauge reads five psig at sea level elevation, the corresponding absolute pressure is
___________ psia. Fractional
The portion of the electromagnetic spectrum to which solar collectors respond is _____ and near-
infrared radiation. Visible light
During winter, ________. Daylight is shorter and the Northern Hemisphere is angled
away from the sun
Unless equipped with OSHA or Canadian Standards Association (CSA) approved ground-fault
circuit interrupters, portable electric lighting used in wet and-or other conductive locations as, for
example, drums, tanks and vessels, shall be operated at ______ volts or less. 12
, Receivers are usually required in systems having: Evaporative condensers
An important feature of a refrigerant receiver, in the case where the liquid line to the evaporator
comes out of the top of the receiver, is a: Dip tube
A pressure regulator is constructed so that a rise in ____________ steam pressure reduces off the
inlet flow of supply steam. Downstream
A vacuum breaker is used to avoid which of the following Negative gauge pressure
Lock-out relays are used in air conditioning systems to: Prevent compressor short-cycling
When measuring the winding resistance of a split-phase compressor motor, the smallest value
will be measured between the: The run terminal and the common terminal
Cavitation in a pump pumping hot water: A. Partial Correct: Makes a pump noisy
B. Partial Correct: Is the result of water boiling into the steam
C. Partial Correct: Is the result of insufficient NPSH
The amount of heat removed to lower the temperature of 15 lbs. of water from 48 degrees F to 39
degrees F is: 135 Btu.
Heat = Weight (lbs.) x Specific Heat (Btu/lb. per degree) F x Temperature (degrees F) = 15 x1
(48-39) degrees F = 15 x 1 x 9 = 135 Btu
