Basic Refridgeration

Question 1

What does CFC stand for ?

Answer 1

Chlorofluorocarbons

Question 2

3 types of basic condensers ?

Answer 2

Air cooled
Water-cooled
Evaporative

Question 3

Define Tempature ?

Answer 3

Measure of the intensity of heat of a substance and the measure of its molecular speed expressed in degrees

Question 4

What is a subcooled liquid?

Answer 4

A liquid that has been cooled below the boiling (condensing) temperature at a specific pressure

Question 5

What is super heat

Answer 5

A vapour heated to a temp above its saturation point. After a liquid has vaporized, the heat it continues to absorb raises its temp so that it becomes superheated

Question 6

One ton of cooling is = to _______ btu/hr

Answer 6

12,000

Question 7

A recovery cylinder should be filled a maximum of _____% of its capacity

Answer 7

80%

Question 8

What type of personal protective equitment must be worn to prevent frostbite ?

Answer 8

Eye protection
Hand protection
Proper clothing

Question 9

Is it necessary to obtain a permit before installing ancooling system ?

Answer 9

A permit must be taken out for every installation

Question 10

3 types of metering devices

Answer 10

Thermostatic expansion valve
Capillary tube
Orfice

Question 11

When the refrigerant leaves the condensor it is ?

Answer 11

A hot high pressure liquid

Question 12

One type of filter drier can be used for all types of refrigerant. (True or false)

Answer 12

False

Question 13

List the 6 components of a cooling device ?

Answer 13

Compressor
Evaporator
Condenser
Metering device
Piping
Filter drier

Question 14

Which side of the system is the evaporator considered to be in ?

Answer 14

Low pressure side

Question 15

How many pressure changes will the refrigerant in a cooling system undergo in a complete cycle ?

Answer 15

Two

Question 16

3 types of dehumidifiers

Answer 16

Heat pump
Chemical absorbent
Ventilating humidifiers

Question 17

The heat pump humidifier works under the same basic principles as an air conditioning heat pump. (True or false)

Answer 17

True

Question 18

Why do dehumidifying ventilators do not work well in hot humid climates ??

Answer 18

They bring more outside air into the house which has more moisture in it.

Question 19

Is the condenser upstream or down stream the compressor?

Answer 19

Upstream

Question 20

Is the meter upstream or down stream the evaporator coil ?

Answer 20

Upstream

Question 21

Is the compressor upstream stream or down stream the evaporator coil ?

Answer 21

Downstream

Question 22

Lower pressure means boiling point will ?

Answer 22

Drop

Question 23

Increase in pressure means boiling point will ?

Answer 23

Rise

Question 24

How far must a regulator vent be to a condenser ?

Answer 24

3 feet

Question 25

How many Btu for latent heat of fusion (solid to liquid absorbing heat )

Answer 25

144btu

Question 26

How many Btu for sensible heat (sub cooling )

Answer 26

180 Btu

Question 27

How many Btu for latent heat of vaporization ?

Answer 27

970 Btu

Question 28

The refrigeration cycle involves two _____ changes and two _____ changes

Answer 28

Pressure Transfer

Question 29

High pressure = ____state

Answer 29

Liquid

Question 30

Lower pressure = ________ state

Answer 30

Vapour

Question 31

What’s the job of a compressor in an ac unit ?

Answer 31

Keeps refrigerant flowing at specific pressures and flow rates

Question 32

What’s the job of the metering device ?

Answer 32

To lower pressures

Question 33

What does an evaporator do ?

Answer 33

Absorbs heat from the medium to be cooled .

Question 34

The refrigerant travels through the evaporator, entering as a _____ and leaving as a _____

Answer 34

Liquid Gas

Question 35

What’s a condensers job ?

Answer 35

Remove heat from the system

Question 36

Where do you mount the thermal bulb ?

Answer 36

Mount on the suction line

Question 38

A capillary tube consists of a very small bore tube from ___mm to ____mm in diameter and inbetween ___m to ____m in length

Answer 38

.75mm to 2.25mm (1/32 to 3/32) in diameter 1.5m to 6.1m (5’ to 10’) in length

Question 39

How do we add refrigerant into a unit ?

Answer 39

Liquid in tank to vapour side of compressor

Question 40

Pipe for use in air conditioning and refrigeration is ____?

Answer 40

Designated ACR copper tubeing

Question 41

Acr tubing does not come charged with nitrogen. True or false ?

Answer 41

False

Question 42

Why does ace tubeing come charged with nitrogen ?

Answer 42

Keeps tubeing clean and dry until it is used

Question 43

How is acr tubeing sized ?

Answer 43

Outside diameter

Question 44

Two types of acr tubeing ? And Thier colours

Answer 44

Type k (thick wall) green Type l (thin wall) blue

Question 45

Type k and l are available in two types of tempers what are they ?

Answer 45

Drawn tempers (hard rigid) Annealed tempers (soft flexiable)

Question 46

Flare fittings can be installed on both annealed and drawn temper pipe ?

Answer 46

False only on annealed

Question 47

The filter drier is to be installed with arrows pointing towards the direction of the refrigerant flow. True or false

Answer 47

True

Question 48

What is latent heat and what is it also called ?

Answer 48

Hidden heat When there’s a changed of state without a change of tempature Adding latent heat changes Solid to a liquid or liquid to gas Removing latent heat is vapour to liquid or liquid to a solid

Question 49

What is sensible heat ?

Answer 49

Heat required to change temp of a substance but not change state

Question 50

Licensed jman sheetmetal workers and apprentices in Alberta are allowed to install and service split systems up to and including ________ tons and or _____ btuh

Answer 50

5 tons or 60,000 btuh

Question 51

What is dehydration ?

Answer 51

Common method of evacuation using a vacuum pump to lower the pressure inside the refrigeration system so that air and moisture can be drawn out of the system

Question 52

R-22 is a single _________ compound ?

Answer 52

Hydrochlorofluorocarbon (Hcfc)

Question 53

Can u mix diffrent types of refrigerants together ?

Answer 53

No