NEW
Font size
S
M
L
XL
WorksheetsHVAC FC 07
Total questions: 70
Worksheet time: 35mins
Name
Class
Date
1.
What is the device that removes heat from a mechanical refrigeration system?
a)
condensor
b)
evaporator
c)
compressor
d)
metering device
2.
The total heat load consists of the amount of heat to be removed from a cabinet during certain period, and is the sum of various heat loads per what unit of time?
a)
3 hours
b)
8 hours
c)
24 hours
d)
48 hours
3.
Select the statement NOT RELATED to a chilled water air conditioning system:
a)
they commonly use water towers
b)
the chiller is located on the low side of the system
c)
they are primarily used in residential system
d)
they use water as a secondary refrigerant
4.
Which component is NOT a part of an absorption system?
a)
generator
b)
absorber
c)
evaporator
d)
compressor
5.
Mechanical ventilation topic: Ventilation air shall NOT be ____ from one dwelling to another or to dissimilar occupancies.
a)
required
b)
exhausted
c)
contaminated
d)
re-circulated
6.
A steel piping in a hydronic system needs to be installed. Indicate the Maximum vertical spacing in accordance with MSS.
a)
18 feet.
b)
15 feet.
c)
12 feet.
d)
9 feet.
7.
Stud wall cavities:
a)
can be used as part of the fire-rated assembly
b)
can be used as a return duct if properly fitted
c)
can be used as a plenum for supply air
d)
can convey air up to two floor levels
8.
The pipe size of each section of gas piping shall be determined by using the longest length of piping from the ____.
a)
branch point to the appliance
b)
point of delivery to most remote appliance
c)
the mean of all piping
d)
branch point to the appliance
9.
In a refrigeration system, superheat does NOT normally occur in the
a)
suction line
b)
liquid line accumulator
c)
compressor
d)
top part of the condenser
10.
The access door for a fire damper shall be labeled with letters NOT less than ___ in height.
a)
1/2 inch
b)
3/4 inch
c)
1 inch
d)
1 1/2 inch
11.
Suspended-type unit heaters shall be installed with clearances to combustible materials of NOT LESS than ____ inches at the sides.
a)
18 inches
b)
24 inches
c)
6 inches
d)
12 inches
12.
Which component may be added to a refrigeration system to prvent moisture from entering the compressor?
a)
receiver
b)
accumulator
c)
liquid line filter drier
d)
crankcase pressure regulator
13.
Carbon steel pipe with a wall thickness not less than schedule ____ shall be used for group A2, A3, B2, or B3 refrigerant lines for sizes 1.5 inches and smaller.
a)
80
b)
20
c)
120
d)
40
14.
According to Ohm's Law, to solve the current draw of a circuit, the correct formula would be which of the following?
a)
I=E/R
b)
E=I/R
c)
R=1/E
d)
I=R/E
15.
What percentage of a refrigeration load can be placed on an evaporator regulated by a two temperature valve?
a)
0.2
b)
0.3
c)
0.4
d)
0.5
16.
According to the OSHA safety and health regulation for construction, a fatal accident that results in a death must be reported no later than ___.
a)
1 hour
b)
4 hours
c)
8 hours
d)
24 hours
17.
A mechanical permit is required for all of the following, except ___.
a)
a condensing unit
b)
an air-handeling unit
c)
an enclosed furnace
d)
a portable cooling unit
18.
What is the heat fusion of water?
a)
-109 Btu/lb
b)
41 Btu/lb
c)
32 Btu/lb
d)
144 Btu/lb
19.
The STARTING running voltage used on a 208-volt motor is ___.
a)
187 volts
b)
228 volts
c)
175 volts
d)
208 volts
20.
What is the recommended motor pressure control cut out setting for the defrost cycle of R-22 walk-in cooler?
a)
20 psi
b)
29 psi
c)
34 psi
d)
40 psi
21.
In determining heat load, the symbol letter "K" represents the
a)
heat gain
b)
heat leakage
c)
thermal conductivity
d)
heat transfer coefficient
22.
What minimum width unobstructed access must be provioded on all sides of boilers?
a)
16 inches
b)
18 inches
c)
24 inches
d)
30inches
23.
Commercial refrigeration is the use (in order to satisfy the intended use of a specific space) of mechanical or absorption equipment to control ____.
a)
ambient pressure
b)
mold and mildew
c)
humidity or temperature
d)
ventilation
24.
Slowing the velocity of water through an evaporator will have what effect on the heat transfer?
a)
increase
b)
decrease
c)
no change
d)
slightly improve
25.
There are five principal types of refrigerant flow controls, of the following types listed below, which one is NOT a main type of automatic refrigerant flow control?
a)
Condenser Equalizer Valve
b)
Capillary Tube
c)
Automatic Expansion Valve
d)
Thermostatic Expansion Valve
26.
The compressor on an air conditioning system is running continuously. A possible cause of the problem is
a)
a shortage of refrigerant
b)
an excess of refrigerant
c)
low voltage
d)
an open thermostat switch
27.
A grain is a unit of weight equal to ___, used to indicate the amount of moisture in the air.
a)
1/7 lb.
b)
1/70 lb.
c)
1/700 lb.
d)
1/7000 lb.
28.
According to the IMC, on down-flow HVAC systems and all other coils that do not have a secondary drain or provisions to install a secondary or auxiliary drain pan, a water-level monitoring device shall be installed ______. This device shall shut off the equipment served in the event that the primary drain becomes restricted.
a)
drain line
b)
inside primary drain pan
c)
suction line
d)
outside the primary drain pan
29.
Ducts that operate at temperatures exceeding 120 degrees F shall have sufficient thermal insulation to limit the exposed surface temperature to ____ degrees F.
a)
120
b)
100
c)
180
d)
140
30.
Pressure relief devices, such as a refrigeration fusible plug, located within the machinery room shall terminate outside of the structure at a location NOT LESS THAN _____ feet.
a)
20
b)
25
c)
30
d)
15
31.
To qualify as a HEPA filter under the US government standards, captured airborne particles must be a minimum of how many microns?
a)
0.3
b)
1
c)
1.5
d)
3
32.
Except for a range and dryer connectors, the maximum length of approved listed flexible-metal tubing for fuel gas connectors is ___ feet.
a)
2
b)
3
c)
4
d)
6
33.
The degree-day method is a measure used to help indicate the heating or cooling needed for a given region. Calculations are based on an indoor temperature of ____ as a standard.
a)
28 degrees F
b)
36 degrees F
c)
65 degrees F
d)
72 degrees F
34.
There are various brazing low temperature silver alloys on the market, most have a 35% to 45% silver content. This type of material usually starts melting at what temperature?
a)
starts melting at 1,120 F and flows at 1,145 F
b)
starts melting at 1,140 F and flows at 1,160 F
c)
starts melting at 1.160 F and flows at 1,180 F
d)
starts melting at 1,180 F and flows at 1,195 F
35.
Which method of heat transfer is characterized by heat traveling through a substance by direct contact?
a)
radiation
b)
conduction
c)
convection
d)
combustion
36.
Absolute zero temperature is the temperature at which all molecular motion ceases at approximately ___ degrees Fahrenheit.
a)
-460 degrees F
b)
-450 degrees F
c)
-430 degrees F
d)
-410 degrees F
37.
Energy conservation standards require that each walk-in cooler or walk-in freezer manufactured on or after January 1, 2009, shall contain wall, ceiling and door insulation of at least R-25 for coolers and ____ for freezers.
a)
R-25
b)
R-28
c)
R-32
d)
R-40
38.
The ____ is the automatic shutdown device required in a recirculating air system with ducted supply and return air and an airflow capacity of 3,000 cfm serves one enclosed room.
a)
no device is required
b)
smoke detector
c)
manual switch
d)
temperature sensor
39.
The units of thermal conductivity are Btu/Sq.ft/degrees F/hr. It is the measure of ____.
a)
how quickly heat can travel through material
b)
thickness of a materials R-rating
c)
the efficiency of the heat conductance
d)
U-value of the insulation
40.
How is a fan motor connected electrically to the compressor or motor control?
a)
in parallel and controlled by refrigerant control
b)
in parallel and controlled by thermostat
c)
in series and controlled by refrigerant control
d)
in series and controlled by thermostat
41.
Volatile liquid is located in the ___ and this is in contact with the evaporator of the refrigeration system.
a)
Bi-metal
b)
Solid state
c)
Cap tube
d)
Sensing bulb
42.
Carbon dioxide stack changes with respect to the amount of excess air (oxygen) in the area. Systems will vary in the CO2 content operating between 8% to 12%. If a system uses a oil-fired heating system, what would be the CO2 content of flue gas, given that the excess air in the system was approximately 80%?
a)
0.12
b)
0.1
c)
0.09
d)
0.07
43.
How many CFM of ventilation air is required for a 50,000 Btu/hr infrared heater?
a)
100
b)
200
c)
300
d)
400
44.
When computing heat leakage for a building, the U-value for most types of construction can be obtained from reference books. The unit of measure for U-value is expressed in ___.
a)
Btu/sq-ft/deg.F/Hr
b)
CFM/Hr
c)
heat-flow / square-area
d)
heat-flow / temperature-difference / area
45.
Combustion, ventilation and dilution air regulations state that a fuel burning appliance, installed in a limited space with an opening to supply combustion air shall commence within ___ from the top of the enclosure.
a)
midway between floor and ceiling
b)
24 inches
c)
18 inches
d)
12 inches
46.
Troubleshoot the following conditions: The ohmmeter when across the start capacitor goes to low range, then slowly moves to the high range of the scale.
a)
indicates a short
b)
indicates an open
c)
good start capacitor
d)
bad motor winding
47.
A contractor was asked to drain piping from an air conditioning system. He needs to make sure this piping is not discharging:
a)
to a grassy area
b)
onto a street or an alley
c)
onto a flat roof
d)
into a french drain
48.
A residential bathroom needs to be provided with an intermittent exhaust. THE LEAST "cfm" allowed for this specific area is ___.
a)
100 cfm
b)
25 cfm
c)
50 cfm
d)
75 cfm
49.
According to the International Mechanical Code, the roof top guardrail shall extend not less than how many inches beyond each end of a roof top appliance or unit (RTU)?
a)
30 inches
b)
42 inches
c)
48 inches
d)
72 inches
50.
How long MUST employee injury and incident report forms be retained
a)
three years
b)
four years
c)
five years
d)
seven years
51.
What is the term for a condition where a substance changes from a solid to a gas without becoming a liquid?
a)
evaporation
b)
sublimation
c)
out gassing
d)
condensation
52.
One ton of refrigeration effect equals _____ Btu/hr.
a)
100000
b)
1000
c)
1200
d)
12000
53.
A ____ is used for measuring atmospheric pressure.
a)
pressure gauge
b)
compound gauge
c)
psychrometer
d)
barometer
54.
To prevent dangerous pressures in refrigerating systems and whenever necessary, relief valves are mounted on the units on the ____.
a)
condenser coil
b)
liquid receiver
c)
evaporator
d)
compressor crankcase
55.
What size tap drill should be used for a 12-13 tap?
a)
25/64 inches
b)
27/64 inches
c)
29/64 inches
d)
31/64 inches
56.
About ___ inches are the MINIMUM separation when working with a pressure tap of an 3-inch gas line and the MP gas regulator.
a)
30 inches
b)
24 inches
c)
42 inches
d)
36 inches
57.
The ____ compressor uses a disk with radial impellers that spins rapidly to compress refrigerant.
a)
Scroll
b)
Screw
c)
Reciprocating
d)
Centrifugal
58.
According to OSHA, employees must not perform work on scaffolding if it is:
a)
during a storm or high winds
b)
during extremely cold weather
c)
three times higher than the least base dimension
d)
five times higher than the least base dimension
59.
What precaution must always be used when pressure testing a system with nitrogen or carbon dioxide for leaks?
a)
an oil separator must be installed in the connecting piping to avoid contaminating the system
b)
use a pressure reducing device that has both a pressure regulator and a pressure relief valve
c)
a dryer must always be installed in the connecting piping to prevent moisture from entering
d)
nitrogen must not be left in the system more than a few hours or it will began to react chemically
60.
Passageways around all sides of boilers shall have an unobstructed with of NOT LESS than __ inches.
a)
30 inches
b)
36 inches
c)
18 inches
d)
24 inches
61.
According to the International Mechanical Code, ducts installed within a single family dwelling shall be sized in accordance with the
a)
ACCA Manuel D
b)
ASHRAE Hanbook of Fundamentals
c)
SMACNA HVAC Duct Construction Standards
d)
NAIMA Fibrous Glass Duct Construction Standards
62.
A worker has to install steel gas pipe of nominal size of 2-inch horizontally. This job is being done at a commercial building. Indicate how far apart the horizontal supports must appear.
a)
6 feet
b)
4 feet
c)
10 feet
d)
8 feet
63.
What is the heat of fusion of water?
a)
-109 Btu/lb
b)
41 Btu/lb
c)
32 Btu/lb
d)
144 Btu/lb
64.
Underfloor spaces containing appliances shall be provided with an access opening and unobstructed passageway that is NOT LESS THAN ____ wide and ____ high.
a)
36" x 22"
b)
36" x 36"
c)
22" x 30"
d)
36" x 20"
65.
With the off-cycle defrost method, what is adjusted to restart the compressor when the evaporator is frost free?
a)
low pressure control cut-in setting
b)
capillary tubes
c)
automatic expansion valves
d)
thermostatic expansion valves
66.
Give the correct option when a service opening needs to be covered whilke insulating a duct?
a)
in no case
b)
when the service opening is not frequently used
c)
when a label shows the exact
d)
when a cutout is made
67.
Joints and all refrigerant-containing parts shall be constructed to withstand, without leakage, a pressure of ___ percent of the higher of the design pressure or pressure relief device setting.
a)
1.5
b)
1.25
c)
1
d)
0.8
68.
Identify the most commonly expansion device used on multiple-evaporator systems to provide different temperatures in various cabinets on air conditioning systems.
a)
thermostatic expansion valve
b)
automatic expansion valve
c)
fired orifice
d)
suction pressure valve
69.
When fresh air is brought in by the air conditioning system, what pressure can be maintained in the building to help keep out airborne dirt, dust and pollen?
a)
negative
b)
normal
c)
positive
d)
static
70.
According to the International Fuel Gas Code, exhaust ducts for a domestic clothes dryer shall have a smooth (interior finish and be a) minimum of
a)
0.016 inch thick
b)
0.024 inch thick
c)
0.026 inch thick
d)
0.028 inch thick
Reset
