Acr 1060 Air Conditioning Final Review

Front 1

What is the most popular heating fuel used?

Back 1

Natural Gas

Front 2

What are the 4 main elements of a mechanical refrigeration system?

Back 2

Compressor, Evaporator, Condensor, Expansion Device or Metering Device.

Front 3

Air Conditioning and refrigeration tubing sizes are expressed in terms of:

Back 3

Outside Diameter (OD)

Front 4

What type of copper piping is used in Air conditioning and refrigeration work?

Back 4

Annealed Copper refrigeration tubing (ACR)

Front 5

When laying out offsets _______ elbows should be used.

Back 5

45 degree

Front 6

Tee fittings can cause a condition known as bullheading or:

Back 6

Turbulence

Front 7

Soldering is done at temperatures:

Back 7

Below 800 degree F.

Front 8

Brazing is done at temperatures:

Back 8

Above 800 degree F.

Front 9

The pressure-reducing regulator is set for no more than ________ must be used with acetylene.

Back 9

15 psig

Front 10

When adjusting the torch oxygen system the oxygen regulator turns clockwise until __________ and the acetylene regulator is adjusted to _________.

Back 10

20 psig / 5 psig

Front 11

What is the most common flame used for almost all fusion welding and brazing applications?

Back 11

Neutral flame

Front 12

Nitrogen flowing thru the tubing to keep all the oxygen / air out while being brazed is called?

Back 12

Purging

Front 13

The amount of heat needed to raise the temperature of one pound of water 1 degree F. is called ?

Back 13

British thermal unit (BTU)

Front 14

Heat that can be sensed by a thermometer is called?

Back 14

Sensible heat

Front 15

Heat energy that is absorbed or rejected when a sustance is changing state ( Solid to liquid) without change is called:

Back 15

Latent heat

Front 16

When all the liquid in the evaporator has fully converted to a vapor it is called:

Back 16

Superheated

Front 17

When all the gas has fully converted to a liquid in the condensing unit it is called:

Back 17

Subcooling

Front 18

What are the 3 different ways to move or transfer heat?

Back 18

Conduction, convection, radiation

Front 19

Every square inch of any surface at sea level or Atmospheric pressure is at:

Back 19

14.7 psia

Front 20

The absolute pressure scale is expressed as (PSI) starting from:

Back 20

0

Front 21

Guage pressures can easily be converted to absolute pressures by:

Back 21

Adding 14.7 to the guage - pressure value.

Front 22

Converts low pressure gas to a high temperature high pressure gas:

Back 22

Compressor

Front 23

Converts high temperature high pressure gas to a high pressure liquid (subcooling):

Back 23

Condensor

Front 24

Converts a high pressure liquid (subcooled) to a low pressure liquid:

Back 24

Expansion Device or metering device

Front 25

Converts low pressure liquid to a low pressure gas (superheated)

Back 25

Evaporator

Front 26

Temperature of the gas in the discharge line is ___________ higher than the outside air temperature.

Back 26

20 to 30 degree

Front 27

When subcooled liquid exits the condensing unit the liquid goes thru the:

Back 27

Filter dryer

Front 28

The Thermal expansion valve (TXV)

Back 28

Regulates and maintains the superheat.

Front 29

The optimum temperature inside the evaporator is:

Back 29

40 degree F.

Front 30

The condensor:

Back 30

Rejects heat

Front 31

The evaporator:

Back 31

Absorbs heat

Front 32

A mixture of __________________ is supplied from the metering device to the evaporator.

Back 32

75% liquid / 25% gas

Front 33

What is the color-coded cylinder for HFC 410A?

Back 33

Pink or (Rose)

Front 34

Welded hermetic compressors that are frequently used on appliances, room air conditioners, and central air conditioners below 5 tons are:

Back 34

Rotary Compressors

Front 35

Welded hermetic compressors that have the fewest working parts, a valve is used on the discharge line to prevent reverse rotation.

Back 35

Scroll Compressors

Front 36

The most common type of condenser is called:

Back 36

Fin and tube condenser

Front 37

They work on both the high pressure and low pressure sides:

Back 37

Pressurestat

Front 38

Ensure single direction flow. They prevent reverse flow.

Back 38

Check valves

Front 39

Four common leak detectors:

Back 39

Electronic, ultrasonic, ultraviolet/fluorescent, liquid (bubble)

Front 40

Systems with a partial charge must first be:

Back 40

Recovered

Front 41

The vacuum pump oil should be changed:

Back 41

After every 10 hours of use / Allways immediately after pumping down a wet or contaminated system.

Front 42

A deep vacuum is a vacuum of:

Back 42

500 microns or less (29.90 in. Hg)

Front 43

A triple evacuation is a vacuum of:

Back 43

1000 microns (29.88 in. Hg)

Front 44

When charging a system with 410A the charging cylinder must be selected to:

Back 44

Liquid

Front 45

When recovering refrigerant you should not fill the recovery tank no more than:

Back 45

80% = (CW x .8 + TW - refrigerant already in tank)

Front 46

If a system has a fixed metering device it shall be charged by:

Back 46

Superheat

Front 47

If a system has a Thermal expansion device (TXV) it shall be charged by:

Back 47

Subcooling

Front 48

What is Target Superheat?

Back 48

3 x WB - 80 - DB divided by 2

Front 49

How do you get Subcooling?

Back 49

Liquid line temperature - Liquid guage temperature

Front 50

A range of temperatures in which a zeotrope refrigerant will evaporate and condense for a given pressure.

Back 50

Temperature glide

Front 51

If a leak in a system using a zeotrope refrigerant is repaired:

Back 51

Recharge the system with new refrigerant.

Front 52

What is actual Superheat?

Back 52

Suction line temperature - Suction guage temperature