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WorksheetsHVAC-PP Randomized Final
Total questions: 128
Worksheet time: 1hrs 4mins
Name
Class
Date
1.
At what degrees Fahrenheit below the desired evaporator outside surface temperature should the cut out pressure of a pressure motor control be set?
a)
5
b)
10
c)
15
d)
20
2.
What is the applied voltage across an electric heater with a total current draw of 22 amperes and a resistance of 11 ohms?
a)
230
b)
240
c)
242
d)
248
3.
An adjustable V-pulley for a belt drive motor is moved FURTHER from the other flange. This change will widen the pulley giving the effect of a smaller diameter pulley. The fan speed will
a)
decrease
b)
increase
c)
double
d)
triple
4.
In order to balance the system pressure and crankcase in a hermitically sealed compressor unit what must be done?
a)
Shut system down.
b)
Install a thermostatic expansion valve.
c)
Cycle system several times.
d)
Service the evaporator.
5.
Fabricating a 2 piece 90-degree welded turn using 4-inch NPS carbon steel pipe, what would be dimension A for this layout?
a)
1.1875
b)
1.75
c)
2.25
d)
2.78125
e)
Pg. 2-5
6.
To find the Travel measurement in a common 45-degree offset, what formula would be used?
a)
Run X 1.000
b)
Offset X 1.000
c)
Offset X 1.414
d)
Spread X .414
e)
Pg. 4-1 & 4-2
7.
How many threads per-inch is there for 1/2-inch nominal diameter steel pipe?
a)
18
b)
14
c)
11.5
d)
8
e)
Pg. 4-13
8.
A 2,000-square foot dry cleaning area utilizing a Type II dry cleaning system requires a MINIMUM exhaust air of ___.
a)
4,000 cfm
b)
5,000 cfm
c)
3,000 cfm
d)
2,000 cfm
9.
Heat exists down to absolute zero which is measured at a temperature of
a)
-400 degrees F
b)
-420 degrees F
c)
-440 degrees
d)
-460 degrees F
10.
What controls the temperature difference between the cut-out and the cut-in settings in a temperature control mechanism?
a)
mercury switch
b)
range adjustment
c)
thermostatic adjustment
d)
differential adjustment control
11.
What is the distance between point A to B in the drawing below? FIG. A
a)
28 feet
b)
30 feet
c)
12 feet
d)
15 feet
12.
Among the different types of eye protection, persons who wear glasses should avoid using:
a)
protective goggles with general magnification lenses
b)
spectacles with lenses that are both corrective and protective
c)
protective goggles worn over corrective spectacles
d)
corrective lenses mounted inside protective goggles
13.
In a boiler system, the discharge piping from safety valves and safety relief valves shall
a)
be securely anchored and supported
b)
have no more than 2 elbows
c)
terminate within 60 inches of the floor
d)
have a minimum diameter of 1"
14.
What is the predominant color and lettering color for a piping system that is classified as dangerous?
a)
Red with white letter’s
b)
Yellow with black letter’s
c)
Green with black letter’s
d)
Blue with white letter’s
e)
Pg. 5-22
15.
A service technician is trying to fix a STICKING relay. What should be done in this situation?
a)
file points
b)
replace it
c)
lubricate slide
d)
clean terminals
16.
Proper thermostatic expansion valve sensing bulb placement is dependent on
a)
line size and refrigerant type.
b)
refrigerant type only.
c)
line size only.
d)
oil type only.
17.
A piping system was installed with 316 stainless steel pipe for a piping system to transport Ethyl acetate, is the piping system satisfactory for this chemical?
a)
Yes
b)
No
c)
Pg. 3-42
18.
Select the LEAST unobstructed area of supply and return ducts approved for a warm air furnace.
a)
6 square inches/1,000 Btu
b)
6 square feet/1,000 Btu
c)
2 square inches/1,000 Btu
d)
2 square feet/1,000 Btu
19.
What is the lay length of a 6 X 5 concentric reducer?
a)
5 1/2 inches
b)
6 inches
c)
7 inches
d)
8 inches
e)
Pg. 2-50
20.
What type of device senses an off limit condition, and shuts down the offending piece of equipment in order to prevent a hazardous condition?
a)
an intermittent pilot
b)
an interrupted pilot
c)
a purge
d)
an interlock
21.
In a 22 1/2-degree equal spread offset, what is the approximate run length if the offset was to be 6 inches?
a)
14.48 inches
b)
15.84 inches
c)
14.84 inches
d)
18.54 inches
22.
AT Least, how many clearance space should be available for the supply and return air ducts for a warm-air furnace?
a)
6 square feet/1,000 Btu/h
b)
6 square inches/1,000 Btu/h
c)
2 square feet/1,000 Btu/h
d)
2 square inches/1,000 Btu/h
23.
A contractor is working with auxiliary drain pans in a secondary drain system for an air conditioning system. How deep should be these auxiliary drain pans, AT LEAST?
a)
1-1/2 inches
b)
1-1/4 inches
c)
2 inches
d)
1-3/4 inches
24.
Flexible air ducts, both metallic and non-metallic, shall be ____.
a)
not be limited in length
b)
limited to 6 feet in length
c)
limited to 12 feet in length
d)
limited to 15 feet in length
25.
Air being conveyed from a heat exchanger to an area used for human habitation is defined as ____ air.
a)
return
b)
supply
c)
makeup
d)
combustion
26.
What is the laying length of a 1-inch cast brass solder tee?
a)
3/4 inch
b)
9/16 inch
c)
7/16 inch
d)
5/16 inch
e)
Pg. 3-6
27.
How many floors are unlisted, single wall metal chimney (connectors) permitted to pass through?
a)
0
b)
1
c)
2
d)
3
28.
Choose the correct description for scroll compressors:
a)
There is less vibration than from a reciprocating compressor.
b)
Both scrolls remain stationary during operation.
c)
There are more moving parts than in reciprocating compressors.
d)
They are noisy.
29.
According to the International Mechanical Code, what minimum width unobstructed access must be provided on all sides of boilers?
a)
16 inches
b)
18 inches
c)
24 inches
d)
30 inches
30.
What control device de-energizes the compressor when the pressure falls below set point?
a)
low pressure
b)
low ambient control
c)
discharge relief valve
d)
crankcase pressure regulator
31.
What is the overall dimension (Center to End) of a screwed 1 1/4 malleable elbow rated for 150lbs?
a)
1.125
b)
1.25
c)
1.5
d)
1.75
e)
Pg. 4-15
32.
Clear space above ground of the lowest portion of mechanical equipment suspended from a floor shall be AT LEAST ___ inches.
a)
6
b)
4
c)
10
d)
8
33.
MAXIMUM horizontal hanger spacing for steel pipe for a hydronic system is ____.
a)
16 feet
b)
20 feet
c)
8 feet
d)
12 feet
34.
In a multiple temperature installation, which components are used to eliminate a short cycle condition due to pressure fluctuations?
a)
surge tanks
b)
check valves
c)
solenoid valves
d)
two temperature valves
35.
What type of valve would be placed in a piping system for throttling the flow?
a)
Gate
b)
Ball
c)
Plug
d)
Globe
e)
Pg. 5-7
36.
Return air openings for heating, ventilation and air-conditioning systems shall not be taken from a closet, bathroom, toilet room, kitchen, garage, boiler room, furnace room or unconditioned attic, however, a ___ is not prohibited.
a)
boiler room
b)
furnace room
c)
unconditioned attic
d)
bedroom
37.
Following IMC specifications, duct linings shall be ____ at the area of operation of a fire damper showing a minimum number of inches upstream and downstream of electric-resistance and fuel-burning heaters in a duct system
a)
interrupted
b)
doubled
c)
fireproofed
d)
continuous
38.
According to the International Mechanical Code, plans submitted for a permit from the department having jurisdiction must show in detail the scope of work, that it complies with code, the location of equipment and ______.
a)
be drawn to scale
b)
have three or more sets
c)
be submitted electronically
d)
be drawn on paper or canvas
39.
The degree-day method is used for determining fuel consumption and heating cost during a season. The method uses what indoor temperature as a standard?
a)
72 degrees F
b)
65 degrees F
c)
48 degrees F
d)
32 degrees F
40.
What will be the result ia a thermostatic expansion valve is oversized for a system?
a)
The evaporator will frost.
b)
The evaporator will have a colder temperature.
c)
The evaporator will have a warmer temperature.
d)
The evaporator will alternately be overfed and starved.
41.
A substance used to produce refrigeration by its expansion or vaporization is
a)
brine
b)
an element
c)
a refrigerant
d)
a sodium solution
42.
Grease ducts servicing Type 1 hoods shall be constructed of stainless steel having a MINIMUM thickness of ____.
a)
18 gauge
b)
20 gauge
c)
22 gauge
d)
16 gauge
43.
What is the lay length of a 4 X 4 standard butt weld cross?
a)
3.375
b)
3.75
c)
4.125
d)
4.875
e)
Pg. 2-55
44.
Which instrument is used to obtain air velocity values?
a)
hydrometer
b)
pedometer
c)
odometer
d)
anemometer
45.
When louver and grill design and free area are NOT known, what design should be used for combustion openings?
a)
All louvers must have a 50% free area.
b)
All louvers must be in a fixed open position.
c)
Metal louvers will have a 25% free area and wood louvers will have a 75% free area.
d)
Wood louvers will have a 25% free opening and metal louvers will have a 75% free opening.
46.
What does a sling psychrometer measure directly?
a)
temperature and dew point
b)
heat and cold
c)
gain and drops
d)
wet bulb and dry bulb
47.
Flow through a swing check valve is straight-way, what type of valve has this same flow?
a)
Globe valve
b)
Gate valve
c)
Butterfly valve
d)
Angle valve
e)
Pg. 5-6
48.
What effect does a thermostatic expansion valve with a discharged power element have on an evaporator?
a)
saturates the evaporator with refrigerant
b)
liquid in suction line
c)
a high suction pressure
d)
a starved evaporator
49.
The ____ shall be separated from the plenum by a thermal barrier complying with the International Building Code.
a)
fire sprinkler piping
b)
foam plastic insulation
c)
pneumatic tubing
d)
wiring
50.
The mathematical formula to find the circumference of a circle is:
a)
3.1416 X radius
b)
3.1416 X hypotenuse
c)
3.1416 X tangent
d)
3.1416 X diameter
e)
Pg. 5-69
51.
What is the lay length for a 3-inch nominal diameter raised face weld neck flange, rated for 150lbs?
a)
2 1/4 inch
b)
2 7/16 inch
c)
2 1/2 inch
d)
2 3/4 inch
e)
Pg. 4-68
52.
Trouble shooting a valve that the handwheel turns without stopping at extremes, what is the cause of this?
a)
Wedge damaged
b)
Seat damaged
c)
Broken stem
d)
Loose connections
e)
Pg. 5-9
53.
The outside diameter for 10-inch carbon steel pipe is:
a)
10.020 inches
b)
10.750 inches
c)
33.770 inches
d)
40.500 inches
e)
Pg. 5-17
54.
In an R-22 system, evaporator pressure is 60 pounds. What is the corresponding saturated refrigerant temperature?
a)
34 degrees F
b)
40 degrees F
c)
45 degrees F
d)
55 degrees F
55.
Scheduled or maintenance of a refrigeration system may require welding or brazing, what would be the largest concern with respect providing sufficient ventilation?
a)
the reduction of oxygen would make it hard to breath
b)
heat generated could injure personnel
c)
flourocarbons may become toxic
d)
carbon monoxide may form
56.
Most copper tubing used in air conditioning and refrigeration work is know as ACR tubing, available om soft and hard types. According to the Modern Refrigeration and Air Conditioning textbook, what is the most common type of ACR copper tubing used in the industry today?
a)
D
b)
M
c)
K
d)
L
57.
How many mitered joints is there in a 3-piece 90-degree welded turn?
a)
1
b)
2
c)
3
d)
4
e)
Pg. 2-12
58.
Conduction is the flow of heat between parts of a substance by molecular vibrations. Heat causes solids to become liquid or gases, and conduction travels from
a)
between objects that are indirectly connected
b)
between materials that are insulated
c)
from larger to smaller objects
d)
from warmer to colder objects
59.
Absorption systems are used successfully for air conditioning comfort cooling installations. MOST of these systems use ___ as the refrigerant, and various chemicals as the absorber.
a)
freon
b)
helium
c)
water
d)
nitrogen
60.
What instrument measures moisture in the air?
a)
manometer
b)
hygrometer
c)
pitot tube
d)
anemometer
61.
According to OSHA regulations, before connecting a regulator to a fuel gas cylinder valve, what must take place?
a)
Crank the seal with a metal rod.
b)
Tap the regulator with wrench to loosen any dust or dirt on it.
c)
Open the valve quickly until a cracking sound is heard.
d)
Open the valve slightly and close it immediately.
62.
What type of check valve should be chosen whenever the system has globe valves installed in the piping system?
a)
Swing
b)
Lift
c)
Ball
d)
Plug
e)
Pg. 5-8
63.
In a residential building, the minimum wall thickness of an 8-inch round aluminum duct must be what minimum gauge thickness?
a)
24
b)
26
c)
28
d)
30
64.
For occupancy safety compliance, how are refrigeration systems classified?
a)
application
b)
type of refrigerant
c)
toxicity of refrigerant
d)
degree of probable leakage
65.
What is any portion of a refrigerating system under condenser pressure?
a)
cooling system
b)
circulating system
c)
high side
d)
low side
66.
What is the laying length of a 3-inch 45-degree butt welded long radius elbow?
a)
2 inches
b)
2 1/4 inches
c)
2 1/2 inches
d)
3 1/8 inches
e)
Pg. 2-42
67.
What type of gasket is recommended to be used on a high-pressure steam line?
a)
Hard rubber
b)
Copper
c)
Aluminum
d)
Spiral-wound metal
e)
Pg. 4-123
68.
What type of valve has the same characteristics as a globe valve?
a)
Angle valve
b)
Plug valve
c)
Ball valve
d)
Gate valve
e)
Pg. 5-7
69.
To cool down 20 pounds of water from 85 degrees F to 45, how much heat must be removed?
a)
1,600 Btu.
b)
1,500 Btu.
c)
1,200 Btu.
d)
800 Btu.
70.
Capillary tube capacity is determined by the pressure difference, length of the tube, and inside diameter of the tube. What size length tube would be required given the following: -high-temperature R-22 system -1/2-horsepower compressor
a)
108-inch length and .064 ID.
b)
98-inch length and .052 ID.
c)
88-inch length and .040 ID.
d)
78-inch length and .031 ID.
71.
What is the weight per foot of water in a 10-inch steel pipe schedule 40?
a)
34.16
b)
31.13
c)
30.41
d)
31.56
e)
Pg. 5-11
72.
Chimneys and vents topic: a vent connector shall NOT BE SMALLER than the size of ___ according to the appliance manufacturer instructions.
a)
the flue collar of the appliance it serves
b)
3 inches
c)
4 inches
d)
6 inches
73.
Which of the following refrigerant control devices cannot be adjusted?
a)
electric solenoid valve
b)
capillary tube
c)
automatic expansion valve
d)
thermostatic expansion valve
74.
A technician is installing an electrical-powered appliance. A guardrail will be installed later on. International Mechanical Code must be implemented. The roof is 8 ft. above the grade be;ow. What would be the LEAST distance between the appliance and the roof edge?
a)
8 feet
b)
10 feet
c)
6 feet
d)
4 feet
75.
Smoke dampers, as referenced in the mechanical code, are intended to restrict the ___.
a)
spread of smoke through the duct in an air-handling system
b)
discharge of smoke through smoke-evacuation systems in atriums
c)
operating temperature of unlisted high-heat solid-fuel-burning appliances
d)
amount of smoke exhausted by commercial kitchen hood-ventilation systems
76.
When adjusting superheat setting with a thermal expansion valve, what effect does increasing the superheat have on the system?
a)
starves the evaporator
b)
floods the evaporator
c)
cools the evaporator
d)
none of the above
77.
The measurement of which flue gas is an indicator of the efficiency of the combustion process?
a)
N (nitrogen)
b)
CH4 (methane)
c)
CO (carbon monoxide)
d)
CO2 (carbon dioxide)
78.
What is the required length of bolt for a 3/8-inch U bolt to fit a 1 1/2-inch nominal pipe size?
a)
6 3/4 inch
b)
7 3/8 inch
c)
8 inches
d)
8 3/4 inch
e)
Pg. 2-66
79.
What is the lay length of a 2-inch 45-degree cast brass solder elbow?
a)
45185
b)
45054
c)
44989
d)
45115
e)
Pg. 3-7
80.
What are the parts of a common offset?
a)
Run
b)
Offset
c)
Travel
d)
All of the above
e)
Pg. 4-1
81.
Installing a gate valve that has split or double disc, what position is recommended for the stem?
a)
Stem vertical with the handwheel down
b)
Stem horizontal with the handwheel up
c)
Stem vertical with the handwheel up
d)
Stem vertical with the handwheel down
e)
Pg. 5-6
82.
Joints between chilled water systems and other metallic piping shall be made with ___.
a)
brazed joints
b)
galvanic fittings
c)
welded joints
d)
di-electric fittings
83.
Good practice demands that when a tube constrictor is used to prep a brazed joint, the tubes should be as close as ___ to each other.
a)
.003"
b)
.033"
c)
.300"
d)
.303"
84.
What are the U-value and R-value of 4" thick concrete flooring, with no finish?
a)
U=0.650 R=1.54
b)
U=0.310 R=3.23
c)
U=0.136 R=7.93
d)
U=0.620 R=1.61
85.
What would be the approximate Dry Bulb temperature of a system, given a wet bulb temperature of 65 degrees F, and a relative humidity of 60%?
a)
65 degrees
b)
70 degrees
c)
75 degrees
d)
80 degrees
86.
The thicker the insulation the less heat will flow through it. If the insulation thickness is doubled (i.e. 1" to 2" thick), what will be the resultant heat flow?
a)
1/4 the amount of heat
b)
1/3 the amount of heat
c)
3/8 the amount of heat
d)
1/2 the amount of heat
87.
As outlet ____ the crankcase pressure regulator opens?
a)
As oulet pressure decreases
b)
As outlet pressure increases
c)
As oulet temperature decreases
d)
As outlet temperature increases
88.
What is the setback for a 20-inch length of bend radius in a 30-degree bend?
a)
5 1/8 inches
b)
5 3/8 inches
c)
5 5/8 inches
d)
5 7/8 inches
e)
Pg. 1-14
89.
The one component that should be located between a filter-drier and a metering device is a sight glass. However, caution must be taken when brazing the sight glass as a temperature of ____ or higher can adversely affect the color-changing element.
a)
275 degrees F
b)
255 degrees F
c)
235 degrees F
d)
215 degrees F
90.
Of the three types of condensers used in HVACR applications, which one is MOST affected by low ambient temperature?
a)
water cooled condenser
b)
air cooled condenser
c)
evaporative condenser
d)
coil and shell condenser
91.
A ton of refrigeration equals
a)
240,000 BTU per day
b)
288,000 BTU per day
c)
300,000 BTU per day
d)
360,000 BTU per day
92.
When starting up a new unit, what proceedure should be done first?
a)
open service valves and liquid line valve
b)
charge system
c)
check voltage
d)
jumper out low pressure control
93.
What is the effect of sensible heat?
a)
it changes the state of a substance without changing its temperature
b)
it changes the temperature of a substance without changing its state
c)
it changes both the state of a substance and its temperature
d)
it does not change the temperature or the state of a substance
94.
A permanent factory-applied nameplare (s) shall be affixed to appliances on which shall appear in legible lettering. From the list below, choose the one item that DOES NOt need to be included on the nameplate.
a)
required clearances from combustible construction
b)
type of fuel approved
c)
control schematic
d)
fuel rating in Btu/h
95.
From the list below, select the BEST definition of a vibration absorber:
a)
It is recommended to compress the vibration absorber while installing
b)
The flexible absorber should be fastened to the unit or to a wall at the end pointing away from the vibration source
c)
Only one should be placed on line
d)
They should not be placed on compressor suction lines near the condenser
96.
What is the maximum spacing between pipe supports for a 18 inch steam line designed to operate at 800 degress for the horizontal runs?
a)
50 feet
b)
31 feet
c)
34 feet
d)
36 feet
e)
Pg. 2-68
97.
What is the lay length of a 6-inch steel flanged wedge gate valve?
a)
9 inches
b)
10 inches
c)
10 1/2 inches
d)
11 1/2 inches
e)
Pg. 4-101
98.
The amount of heat conducted through a structure for a given unit of time is referred to as the
a)
U value
b)
R Value
c)
heat transfer rate
d)
infiltration rate
99.
If an HVAC system frequently turns off and on without running the complete programmed cycle, the technician should locate the thermostat for inspection. A thermostat that is exposed to vibration may cause the system to ______.
a)
create temperature lag
b)
short cycle
c)
overshoot the intended destination
d)
overcurrent
100.
When may a replacement listed forced air furnace be installed in an existing closet which is less than 12 inches wider than the furnace and with a minimum clear working space not less than 3 inches along sides, back and top of the furnace?
a)
when approved by the authority having jurisdiction
b)
when such width is in compliance with the manufacturer"s specifications
c)
when approved by the owner
d)
when the installing contractor assumes full responsibility
101.
Piping shall be supported at distances not exceeding the spacing specified in the International Mechanical Code. The maximum interval spacing requirement for a 3/4-inch copper-alloy tubing condensate drain line, installed horizontally shall be:
a)
20 feet
b)
15 feet
c)
10 feet
d)
6 feet
102.
Some old large oil-filled capacitors (found in fluorescent lamp ballasts, and other applications) can leak and create a safety hazard. This dielectric fluid contains what type of material?
a)
Class C
b)
Carbon Dioxide
c)
Carbon Monoxide
d)
PCBs
103.
A typical psychrometric chart graphs relative humidity in percent, dry bulb and wet bulb temperatures. The dry bulb temperatures shown at the bottom of the chart range from ___.
a)
0 degrees F to 100 degrees F
b)
10 degrees F to 103 degrees F
c)
20 degrees F to 107 degrees F
d)
30 degrees F to 170 degrees F
104.
Constants for heat loads are defined in the text Modern Refrigeration and Air Conditioning for a 4 inch thick concrete slab with no finish as
a)
U=0.45; R=1.34
b)
U=0.55; R=1.44
c)
U=0.65; R=1.54
d)
U=0.75; R=1.64
105.
What is the minimum wall thickness for a 1 1/2 inch nominal carbon steel pipe with threaded couplings used to transport liquid Group A1 refrigerant?
a)
Schedule 20
b)
Schedule 40
c)
Schedule 80
d)
Schedule 120
106.
A confined space in which a natural gas appliance has a clearance of 1 inch on the sides and back, and 6 inches on the front requires to have a MINIMUM of ____ permanent ventilation openings communicating with outside air.
a)
two
b)
four
c)
one
d)
three
107.
If the compressor is exposed to cold temperatures, like an air-cooled roof unit, a good operating practice would be to use a ___ circuit during the off cycle to assist with equipment start-up.
a)
crankcase heater
b)
low pressure
c)
high pressure
d)
pressure pump
108.
As a general rule, how many cfm of fresh air per person should be provided to replace oxygen consumption?
a)
10 cfm
b)
15 cfm
c)
20 cfm
d)
25 cfm
109.
A portable refrigerant container shall not be connected to any refrigerating system longer than
a)
Necessary to charge or discharge the system
b)
12 hours
c)
24 hours
d)
48 hoiurs
110.
An air conditioning system thermostat should be placed ___.
a)
near a door or window
b)
near an air duct
c)
where there is a wide range in temperature
d)
where average temperature conditions exist
111.
According to the International Mechanical Code, mechanical joints in refrigerant piping made of annealed temper copper tube shall NOT exceed outside diameter greater than
a)
3/4 inch
b)
7/8 inch
c)
1 1/8 inch
d)
2 inches
112.
During a procedure of soldering or brazing a tube and joint fitting, all air must be removed from the tubing being brazed. This can be best done by purging the tubing with ___.
a)
Ammonia
b)
Oxygen
c)
Air
d)
Nitrogen
113.
Chimneys for residential type or low-heat appliances shall continue AT LEAST ___ above the highest point where they pass through a roof of a building.
a)
5 feet
b)
4 feet
c)
3 feet
d)
2 feet
114.
Following the refrigerant cycle: After the liquid refrigerant enters the evaporator through the refrigerant control, the liquid refrigerant pressure starts working at ___.
a)
at a lower pressure
b)
at a higher pressure
c)
at a higher temperature
d)
fully converted to gas
115.
Fire dampers shall have fire protection rating specified in the International Mechanical Code. If the type of penetration is a 2-hour firewall then the MINIMUM damper rating equals to:
a)
3 hours
b)
2 hours
c)
1-1/2 hours
d)
1 hour
116.
A technician needs to find out the capacity of a 2 psi, 1 1/4 inch schedule 40 natural gas line with a length of 60 feet, a pressure drop of 1.0 psi, and a gas specific gravity of 0.6 the capacity is equals to ____.
a)
6,983 cfh
b)
5,726 cfh
c)
3,821 cfh
d)
4,660 cfh
117.
To prevent the passing of a large amount of oil throughout the system a special separator must be placed in. The line in which this oil separator must go is the ___.
a)
oil
b)
equalizer
c)
suction
d)
discharge
118.
Choose the type of control used in condensing temperature.
a)
Defrost control
b)
Mullion heater
c)
Crankcase pressure regulator
d)
Fan cycling switch
119.
Where the drain pipes from more than one unit are manifolded together for condensate drainage, the pipe or tubing shall be sized according to the equipment capacity. What would be the minimum size if the requirement was 65 tons of refrigerant?
a)
1-1/4 inch
b)
1 inch
c)
7/8 inch
d)
3/4 inch
120.
In concealed locations, where gas piping other than black or galvanized steels is installed through holes or notches in a residence, the pipe should be protected by shield plates of AT LEAST ___ inches in thickness.
a)
1/4 inch
b)
1/8 inch
c)
1/16 inch
d)
1/32 inch
121.
Boyle"s law is the relationship between pressure and volume of gas, assuming temperature remains constant, the rule is:
a)
absolute temperature changes
b)
volume of a gas varies inversely with pressure
c)
gas state never changes with pressure
d)
absolute pressure changes
122.
Which type of fire extinguisher should be used on an electrical fire?
a)
Class A
b)
Class B
c)
Class C
d)
Class D
123.
The process of generating current in a conductor by placing the conductor in a changing magnetic field is called?
a)
induction
b)
resistance
c)
conductance
d)
capacitive reactance
124.
Which refrigerant control that will throttle the liquid refrigerant to a constant pressure on the low pressure side while the compressor is running?
a)
CPR valve
b)
EPR valve
c)
AXV valve
d)
TXV valve
125.
When a HVAC technician works on a commercial unit, all of the following, with the exception of which one, are likely causes of excessive noise?
a)
the compressor pumping excess oil.
b)
pulleys that are out of line.
c)
a squeaky bearing in the electricmotor.
d)
low head pressure.
126.
Pascal's law states
a)
pressure applied upon a confined fluid is transmitted in equal directions.
b)
a constant pressure, mass and temperature of a gas are inversely proportional.
c)
the volume and pressure of a gas vary inversely if the temperature remains the same.
d)
vapor pressure created in a container by a mixture of gasses is equal to the sum of individual vapor pressures of the gasses contained in the mixture.
127.
If you have a 150,000 BTU oputput forced air furnace, what will be the minimum unobstructed supply air opening, unless otherwise listed by the manufacturer?
a)
150 square inches
b)
300 square inches
c)
1000 square inches
d)
1500 square inches
128.
Where all combustion air is provided by a mechanical forced air system, what MINIMUM rate of combustion air shall be supplied?
a)
0.25 cfm per 1,000 Btu/hr.
b)
0.35 cfm per 1,000 Btu/hr.
c)
0.45 cfm per 1,000 Btu/hr.
d)
0.55 cfm per 1,000 Btu/hr
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