if the condenser fan motor goes out what will happen

The systems pressures will increase

What is the purpose of the metering device

To control flow of the refrigerant to the evaporator

Conduction heat transfer is done by

Closely packed molecules in contact with eachother

To find subcooling, you must

Minus liquid line temp from condenser sat temp

What is the suction line accumulator's job

Traps liquid refrigerant to prevent floodback.

What is this a picture of ?

A really strange picture from the 80's, Me at my highschool prom, Me at my senior picture

What does a check valve do?

Only allows refrigerant to flow one direction.

What is the first law of thermodynamics

Energy can not be created or distroyed

How are hermetic compressors cooled?

Superheated refrigerant vapor (cool gas)

How do you check refrigerant static pressure

With the system off reading only the high side gauge

If a Technician connects his gauges and does not purge the air from his hoses, what will happen

Air/Non condensables will be added

Adding fins to an evaporator will

Increase the heat transfer rate by increasing surface area

The change of 1 degree temperature increase in 1 lb of water

What does the compound gauge read

Above and below atmospheric pressure

what two temperature readings do you need in order to use a manufacturers charging chart

indoor wet bulb and outdoor dry bulb

A creepy picture of a birthday in Norway, Miss Kitty's birthday, Just plain odd, Someone who really loves her cats

studbud

Fundamentals of refrigeration final review

103 termsStudBud Administration576 plays

Class review of the refrigeration school's fundamentals of refrigeration class

Flashcards103 cardsFPractice quizPHost liveL

Questions 103

Answers

1
How does radiant heat travel?
As a fluid to a sink source
four quarters equal one dollar
In wave form
Through latent to sensible heat change
2
if the condenser fan motor goes out what will happen
The compressor will draw lower than normal amperage
The systems pressures will increase
The system will have a high subcooling
The txv will adjust for problems on the systems high side
3
What is the purpose of the metering device
Evaporator pressure= bulb pressure+ spring pressure
To collect money for parking for the city
To control flow of the refrigerant to the evaporator
To insure the liquid enters the condenser
4
Conduction heat transfer is done by
Closely packed molecules in contact with eachother
Natural draft
In a wave form
Fluid heat transfer
5
To find subcooling, you must
Minus evap sat temp from liquid line temp
Minus liquid line temp from condenser sat temp
take indoor wet bulb and outdoor dry bulb
add condenser sat to liquid line temp and divide by 2
6
Latent heat is rated in
Kelvin temperature
Sensible heat
Rankine Temperature
BTU's
7
A heatpump with a TXV metering device with an undercharge will have
High superheat, and High subcooling
Low superheat, high subcooling
High superheat, low subcooling
I don't know
8
How many BTU’s per ton of AC
12,000
I Really don't know
5.7 Hemi
400
9
How many tons of refrigeration is 12,000 BTU’s
3.14 is Pi
1.0
1.1123
1.93
10
Lowering the clearance space between the valves and the piston on a recip compressor will
Decrease air flow across the condenser
Increase compression capacity
Decrease compression capacity
Increase in system performance
11
The Thermoexpansion valve bulb operates under varying load conditions and functions using _____
Suction line pressure
Suction line position
Liquid line temperature
Suction line temperature
12
Sensible heat can be measured in
The change of state of a liquid to a vapor
Dew point
Fahrenheit
Wet bulb
13
What is the suction line accumulator's job
Sub cools vapor to a liquid
Prevents superheated vapor from getting to the compressor
Rejects moisture from the system
Traps liquid refrigerant to prevent floodback.
14
What kind of compressor is field serviceable
Hermetic
Rotary
Semi Hermetic
Semi truck
15
What is the typical cycle evaporator split
35.7°C
35.7°F
20°C
20°F
16
The condenser fan blade is a
Propeller blade
Flat blade
Centrifugal Blade
Auger blade
17
A liquid will____ heat when it vaporizes or boils
Freeze
Sublimination
Absorb
Reject
18
What is this a picture of ?
A really strange picture from the 80's
Me at my highschool prom
Go darth vader
Me at my senior picture
19
What does a check valve do?
Opens with superheat
Only allows refrigerant to flow one direction.
Is a fixed metering device
Only allows refrigerant to flow in three directions
20
What is the first law of thermodynamics
Heat travels from hot to cold
Energy can not be created or distroyed
Atmospheric pressure is 0 psia
Superheat means everything to a microwave
21
A screw compressor uses
Compresses refrigerant at the evaporator
Auger Screw to compress gas
Passive aggressive devices
Centrifugal Force
22
How are hermetic compressors cooled?
Subcooled refrigerant
liquid refrigerant
Very hot refrigerant saturated gas
Superheated refrigerant vapor (cool gas)
23
What happens if my sensing bulb on my TXV is not insulated
The Condenser will be underfed
The Evaporator will be Overfed
The Evaporator will be Underfed
The Condenser will be overfed
24
What type of compressor uses a rolling pistion
Rotary
Reciprocating
Vanilla ice
Centrifugal
25
A magnehelic measures
Static pressure drop
Static Cling
Static pressure increase
Temperature
26
What component in a refrigeration system turns refrigerant into liquid
Evaporator
R-410A is radical
Compressor
Condenser
27
Forced air fans
Push air across the coil
Pulls air across the coil
Water droplets through the coil
Uses the Scooby doo effect
28
Water in the system can cause
Freeze up at the metering device
all of the above
Corrosion of metals
Valve Failure
29
How do you check refrigerant static pressure
With tie system running on the high side
with the system running on the low side gauge
With the system off reading only the high side gauge
with the system off on the low side gauge
30
What is a vacuum read in
PSIA
Feet of GH
Inches of mercury
14.7 psia
31
A system that uses pumps and fans for heat transfer is called
Activate once card is recieved
The Delorian effect
Active
Dielectric unions
32
What does the high side pressure gauge read?
Superman
PSIA
Above and below atmospheric pressure
Above atmospheric pressure
33
A capillary tube metering device can adjust to a wide range of varying load conditions
True
False
34
If a Technician connects his gauges and does not purge the air from his hoses, what will happen
Nothing, its ok to do this
The unit wont let that happen
Air/Non condensables will be added
The unit will explode
35
Split systems with a capillary metering device systems are charged using which method
saturation temperature
Soda can cold
Super heat
Subcooling
36
What component in the system raises the temperature of the refrigerant above ambient air temp.
Evaporator
Compressor
Condenser fan motor
Mc Donalds is good
37
Adding fins to an evaporator will
Increase the heat transfer rate by increasing surface area
Protects evaporator tubing
Decrease system capacity
Directs airflow better but doesn't help heat absorbtion
38
On a heat pump system with a TXV to increase superheat the tech must
Turn the adjustment counterclockwise
Turn the adjustment clockwise
Fully backseat the adjustment
Fully front seat the adjustment
39
What component is between the liquid line and the evaporator line
Condenser fan motors are expensive
Parking metering device
metering device
Compressor
40
If the condenser refrigerant saturates at 125 ° and the liquid line temp is 120° what is the SC
10°F
10°C
5°C
5°F
41
1 BTU equals
The change of 1 degree temperature increase in 1 lb of water
1° F sensible heat
The increase of 1°F in 1 lb of water
42
What does the compound gauge read
Atmospheric and absolute pressure
Above and below atmospheric pressure
Conventional pressure
Only above PSIA
43
2 low pressures on both low and high side with a high superheat and low subcooling has
Overcharge
undercharge
I haven't the slightest clue
Air and Non condensables
44
The color code sequence for the manifold gauges is/are
High side blue, low side red
High side red, low side yellow
High side yellow, low side blue
high side red, low side blue
45
How many CFM of air flow per ton of AC
Ford Powerstroke 6.7
6.2 Litre Duramax diesel
400 CFM
350 CFM
46
What are the basic two types of valves used on reciprocating compressors
Speed and Spring
Ring and Reed
Ring and Spring
Ring and Revolver
47
Induced fans
pulls air across the coil
causes water to condense in the compressor
Use centrifugal force
pushes air across the coil
48
Before the vacuum pump is turned on all the refrigerant must be removed from the system
No
Way false
Yes
True
49
A manometer measures pressure in
Atmospheric
Inches of water column
Absolute
PSIG
50
what two temperature readings do you need in order to use a manufacturers charging chart
evaporator saturation and suction line temp
indoor dry bulb and outdoor wetbulb
indoor wet bulb and outdoor dry bulb
indoor dry bulb and outdoor dry bulb
51
Who is this
A creepy picture of a birthday in Norway
Miss Kitty's birthday
Just plain odd
Someone who really loves her cats
52
A system that doesn't use fans or pumps for heat transfer is known as
A day that will live in infamy
Passive system
Active system
Passive aggressive system
53
A hermetic compressor that uses a stationary scroll and a moving scroll is called
Scroll compressor
Chiller compressor
Corkscrew compressor
Mazda rotary engine
54
What comic book series is this?
Spawn
Captain Caveman
Batman
55
Specific heat capacity is?
Heat that is really specific
The calculation of finding a system's superheat
The measurement of how efficient a flux capacitor is
the amount of heat required to increase temperature
56
The superheat on the typical cycle should be
10°F
10° Latent
5°C
10°C
57
An overcharged AC system with a fixed metering device will have
A sign saying that is was overcharged by the previous tech
Rocky mountain high subcooling
Normal superheat
Low super heat, high subcooling
58
What are 3 Types of Metering devices
Fixed orifice, The dog ate my homework, Capillary tube
Fixed transmission, TXV, Capillary tube
Fixed orifice, TXV, Caps are awesome to wear
Fixed orifice, TXV, Capillary tube
59
what is the purpose of the condenser coil
Reject H.O.C
Absorb heat
Absorb H.O.C
Reject heat
60
To increase the evaporator pressure in an automatic expansion valve you need to
Turn the adjustment counterclockwise
Add more refrigerant- it fixes everything
Turn the adjustment clockwise
Remove the insulation from the sensing bulb
61
Changing the temperature and____ can change the boiling point of a liquid
Heat
Pressure
State of the union
Switch to GEICO
62
What does latent heat change?
The state of a substance (change of state)
Is read at sea level
Requires a source and a sink
Sensible Temperatures
63
What is the typical cycle evaporator saturation temperature.
32°C
5° C
40 °F
50°C
64
When evacuating a system, you must use
micron gauge, vacuum and scale
Vacuum pump, manifold gauges and micron gauge
recovery tank, manifold gauges and a scale
Vacuum pump, manifold gauges, and a digital psychrometer
65
Who is this iconic musician
Cup O noodles
Flava Flav
Jolly Rancher
Ice T
66
2 high pressures on both low and high sides with low superheat and high subcooling has an
Undercharge
Overunder charge
Air and Non condensables
Overcharge
67
Barometric and atmospheric pressures are
Are measured in BTU's
The same pressure
Very different in nature
Opposite
68
_____ is force per unit area
Temperature
Pressure
R-22
BTU's
69
Reciprocating compressor valves operate by
Cylinder Pressure Difference
Latent heating
Superheat
Liquid pressure
70
One ton of refrigeration is equal to ______ BTU's per hour
12,000
400
29.9"HGTV
14.7
71
In all metering devices, the refrigerant must _____ as it changes from a hot liquid to cold liq
Superheats
Condenses
Flashes
Increase in pressure
72
A Vacuum is
Something that is really really expensive
At sea level pressure
Measured in absolute psig
Less than atmospheric pressure
73
What is this that ran up during a family picture
The Rare Lake Tahoe water skiing squirrel
Uncle Saul
A curious creature
Something that was well timed
74
On a AC system, if your high side is low and your low side is high, what is the problem?
High condenser load
Compressor valves are bad
Air and non condensables
There is a break in the return ductwork
75
If I have a dirty evaporator coil, is my superheat going to be high or low
Extremely super high
I dont know
Low
Extremely high
76
13 SEER 5 ton systems have a bigger condenser coils than a 10 SEER 5 ton condenser
True
False
77
what movie is this car from?
Despicable me
Land of the lost
The A team
Back to the Future
78
What is the second law of thermodynamics
Heat travels from hot to cold (high to low)
heat travels from cold to hot (low to high)
Sensible heat increases with pressure
Latent heat travels to sensible heat
79
What is the purpose of the evaporator
Absorb dust from ductwork
Absorb heat
Reject heat
Humidify the air
80
Vapor will _____ heat when it condenses
Freeze
Reject
Absorb
Sublimination
81
What two components in the system control the pressures in the system
Compressor and the Evaporator
Compressor and Metering device
Compressor and Condenser
Heat from the evaporator and the TXV
82
If I have a restriction at my metering device, what will my discharge pressure be
High
Extra Nice
Low
Extra specially low
83
A Natural convection system is also called
An active system
An Active imagination system
A passive imagination system
A passive system
84
Before opening the system for a repair of a major component, what must you do first?
Recover the refrigerant
Check for air and non condensables
Pull a vacuum of 29"Hg
Replace the Shindler valve cores
85
Higher temp and high humidity will produce a lower atmospheric pressure
True
False
True and False
No Way man
86
What movie is this scene from?
Indiana Jones and the Last Crusade
Office space
Raiders of the Lost Ark
Back to the Future
87
What is the typical cycle condenser split
45°Kelvin
30°C
30°F
32.5°F
88
What is convection heat transfer
In a wave form
Friction induced heat
It is the transfer of heat through a fluid medium
Subcooling found in the evaporator
89
What component in the system changes the state of refrigerant from a liquid vapor to a vapor
Compressor
Metering device
Evaporator
Condenser
90
Who is this star of the insurance industry
Doe
Flow
Flo
Noe
91
What is this a picture of ?
Some really strange people
A picture from Awkward family Photos
Me and my promdate
Poor animals
92
To find Superheat, you must
add the suction line temp to the evap sat temp
weigh the refrigerant
suptract evap sat temp from condenser sat temp
Minus evap sat temp from suction line temp
93
Balance port TXV's have
Can operate only in cold climates
A wider range of operating conditions than normal TXV's
Are only used on chillers
Are sensitive to system changes
94
If my indoor blower motor fails, will my suction pressure be high or low
Noe
High
Foshoe
Low
95
At sea level, 0 psig is equal to ____ PSIA
23"HG
0 PSIG
14.7
500 microns
96
Who is this super hero
Super man
Super Woman
Super Guy
Super heat
97
Refrigerant enters the Evaporator as a
Superheated Vapor
Saturated refrigerant (80 percent liquid, 20 percent vapor)
Liquid
Vapor only
98
What is this?
The north American snow squirrel
Sir Squirrels alot
One of our furry friends
Owner of a heating and air conditioning company
99
What's a perfect absolute vacuum
0 psi absolute
14.7 PSIA
0"Hg Absolute
29.9"Hg
100
Metals that are used for their good electrical conductivity
Are also great for their quick thermal qualities
Are also bad for use in thermal energy conduction
Arent generally used on high SEER units
Are good for vibration absorbtion
101
A perfect vacuum is
1000 microns
0"psig
29.9 "Hg
10'Hg
102
At the hottest part of the day, an AC system containing moisture can cause?
Decrease the sensing bulb pressure
I don't know
Decrease in compressor amps
The moisture to migrate to the metering device and freeze up
103
A Centrifugal compressor moves refrigerant by
Positive displacement
Centrifugal Force
Reciprocation
Core compounds

Fundamentals of refrigeration final review Flashcards | StudBud