Air Conditioning and Refrigeration Service

Assuming normal atmospheric pressure atwhat temperature would R134a boil?

• -26.3 degrees C
• -26.3 degrees Fahrenheit
• -103.3 degrees C
• -103.3 degrees Fahrenheit

What is the value of optimum effective temperature in winter?

• 17
• 18
• 19
• 20

What is the job of the expansion device?

• begin changing liquid into vapor by creating a pressure drop
• begin subcooling liquid by warming the vapor
• begin superheating vapor by cooling the liquid
• maintaining a constant pressure from the high side to the low side

Which of the following is true about the optimum effective temperature for human comfort?

• Same in winter and summer
• Not dependent on season
• Lower in winter than in summer
• Higher in winter than in summer

A chemical compound that is used as the heat carrier, which changes from gas to liquid and then back to gas in the refrigeration cycle

• condenser coil
• cooling coil
• evaporator
• refrigerant

Exclusively used for carrying materials and shall not carry any person.

Designed to achieve the environmental requirements of the comfort of occupants and a process.

• Passive
• Cooling
• Active
• HVAC
• Air
• Conditioning
• System

The state of Refrigerant at point A is ........

• Liquid
• Vapor
• Mixture ( liquid + vapor)

What does a Thermal Xpansion Valve do?

• Cleans, dries and filters the refrigerant
• It controls the quantity of refrigerant entering the evaporator
• Allows for an increase in pressure and temperature prior to entering the condenser
• It acts as a safety device if the compressor is over pressuring the system

What is a heat exchanger that induces condensation on the pressurized refrigerant, so that it changes phase from a gas to a liquid?

• condenser
• evaporator
• expansion valve
• radiator

5. A 30-ampere branch circuit may supply fixed lighting units in:

• A dwelling
• Any occupancy other than dwelling units when heavy-duty lampholders are used
• Any type of occupancy
• Any occupancy other than dwelling units when standard-duty lampholders are used

What is the state of the refrigerant leaving the metering device in a refrigerator?

• 50 percent liquid and 50 percent vapor
• 25 percent liquid and 75 percent vapor
• 25 percent vapor and 75 percent liquid
• 100 percent liquid

_________ are the devices that monitor their environment and record or send that information (data) to a computer processor.

• Sensor
• Cloud
• Camera
• Hardisk

What is the state of the refrigerant entering the compressor?

• High pressure, high temperature, 100 percent superheated vapor
• High pressure, high temperature, 100 percent subcooled liquid
• Low pressure, low temperature, 100 percent superheated vapor
• Low pressure, low temperature, 100 percent subcooled liquid

9. The NEC allows wall-switch controlled receptacles in dwelling units in lieu of lighting outlets in all habitable rooms except:

• Basement and attic
• Living and family rooms
• Bedrooms
• Kitchen and bath

The state of Refrigerant at point B is ........

• Mixture (vapor + liquid)
• vapor
• Liquid

The R 134a cylinder color is ........

• Green
• Light blue
• White

43. Receptacles installed on 15- and 20-ampere branch circuits must always be of what type?

• Duplex receptacles
• Grounding type
• Twist-lock receptacles
• Three-prong type

Which engine driven device compresses refrigerant and pumps it through the air conditioning system?

• condenser
• A/C lines
• receiver/Dryer
• compressor

The process of lowering the temperature of a substance below that of its surroundings

• air conditioning
• condensation
• evaporation
• refrigeration

Every occupant of a high-rise commercial building needs to take lifts at least _____ times a day, in the morning, during lunch and after office hours

• THREE
• FOUR
• FIVE
• TWO

a dynamic and responsive architecture that provides every occupant with productive, cost-effective and environmentally approved conditions through a continuous interaction among its basic elements; Places, Process, People, Management, Interrelation between them.

31. Which one of the following voltages is not standard?

• 120 / 277
• 480Y / 277
• 120 / 240
• 600Y / 347

An electric motor shall not drive more than _____ escalator.

• one
• two
• three
• four

If contamination within an airconditioning system is suspected and a flushing procedure is to be carried outwhat component should also be changed?

• Compressor
• ReceiverDrier
• TXV
• Condenser

30. Service conductors run above the top level of a window shall be permitted to be less than the _____ requirement.

• 3-foot
• 6-foot
• 8-foot
• 10-foot

14. EMT shall be supported at least every:

• 4 feet
• 8 feet
• 10 feet
• 15 feet

44. What is the maximum voltage allowed to supply listed electric-discharge lighting in residences, hotels, motels and similar occupancies?

10. Insulated conductors of No. 6 or smaller intended for use as grounded conductors in a circuit must be either of the following colors:

• Blue or black
• Red or black
• White, gray or have three continuous white stripes on other than green insulation
• Orange or yellow

Why must refrigerant be recovered from the A/C system before any A/C parts are replaced?

• released refrigerant can cause personal injury
• refrigerant is under pressure
• to prevent refrigerant from escaping into the atmosphere
• All of these

elevators which are powered by a piston that travels inside a cylinder.

The name of part No. (1) is .......

• Condenser
• Evaporator
• Compressor

35. What percent of fixed electric space heating loads must be used in calculating the total connected load on a branch circuit or feeder?

• 100%
• 125%
• 150%
• 200%

What state is the refrigerant in when leaving the compressor?

• 100 percent Low Pressure, low temperature, superheated vapor
• 100 percent High Pressure, high temperature, superheated vapor
• 100 percent Low Pressure, low temperature subcooled Liquid
• 100 percent High Pressure, high temperature subcooled Liquid

Where would you expect to find a highpressure liquid within an AC system?

• Between the compressor and the TXV
• Between the TXV and the Evaporator
• Between the compressor and the condenser
• Between the Condenser and the TXV

32. Where a feeder conductor supplies continuous loads, the rating of the overcurrent device shall not be less than the noncontinuous load plus what percent of the continuous load?

• 100%
• 110%
• 150%
• 125%

The name of part No (4) is...........

• Condenser
• Capillary tube
• Evaporator

The Simple Refrigeration cycle consists of .....

• Three Mechanical parts
• Four Mechanical parts
• Five Mechanical parts

39. When outside overhead wiring is used, with no messenger cable, what is the minimum size copper wire allowed for spans up to 50 feet?.

• No. 6 AWG
• No. 8 AWG
• No. 10 AWG
• No. 12 AWG

How should R134a be stored to meet safetyrequirements?

• Under pressure as a vapour
• Under pressure as a gas
• Under no pressure as a vapour
• Under no pressure as a gas

46. The equipment grounding conductor contacts of receptacles and cord connectors must be grounded by:

• Connection to the equipment grounding conductor
• Aluminum ground clips
• Aluminum conductors
• Aluminum ground clamps

Which of the following would be carriedout to confirm a system contained no refrigerant?

• Press the service port valve on the low pressure side and listen for a gas leak
• Connect the gauges to both high and lowpressure ports to confirm a vacuum is present
• Connect the Air Conditioning equipmentand carry out a full recovery
• Connect the gauges to both high and low pressure ports to confirm no pressure is present

16. When a branch circuit feeds both noncontinuous and continuous loads, the circuit must be sized to accommodate 100% of the noncontinuous load plus what percent of the continuous load?

• 110%
• 115%
• 120%
• 125%

The name part (2) is ...........

• Compressor
• Condenser
• Capillary tube

Which of these is NOT a refrigerant used in automotive A/C sytems?

• R1234yf
• R12
• R134a
• R2D2

What is the temperature of the line at the outlet of the expansion device if you touch it?

• Warm
• Cold
• Cool
• Very Warm/Hot

A speed governor shall be provided in the escalator, the operation of which will cause the interruption of power to the driving machine should the speed of the steps exceed a pre-determined value, which shall be not more than ____% above the rated speed.

• 30%
• 40%
• 50%
• 60%

What is the temperature of the suction line if you touch it?

• Warm
• Cold
• Cool
• Very Warm/Hot

49. What location requires all 15- and 20-ampere receptacles to be protected with a ground fault circuit-interrupter?

• Those installed within 6 feet of a residential kitchen sink
• Those installed in hotel and motel bathrooms, rooftops and kitchens
• Those installed in residential bathrooms
• All of these areas

48. When receptacles are connected to circuits having different voltages, frequencies, or types of current (ac or dc) on the same premises, what precautions must be taken?

• One type must have a means of disconnection from the circuit when another type is used
• Each receptacle must be tagged for the use intended
• None of the receptacles are allowed to be used without proper supervision
• The attachment plugs must be of a design so they are not interchangeable

What is the job of the evaporator?

• Absorb heat from inside the refrigerator.
• Absorb heat from outside the refrigerator.
• change vapor to liquid
• create flash gas

Where does the low pressure liquid become a gas?

• Evaporator
• Condenser
• TX valve
• Compressor

What does a TXV do?

• Cleans, dries and filters the refrigerant
• It controls the quantity ofrefrigerant entering the evaporator
• Allows for an increase in pressure andtemperature prior to entering the condenser
• It acts as a safety device if thecompressor is over pressuring the system

41. Where outdoor pendant-type lampholders have terminals that puncture conductor insulation to make contact with the conductor, what type of wire must the conductor be?

• Copper-plated solid steel
• Stranded
• Copper-clad solid aluminum
• Solid copper

Which system has moving parts?

a type of vertical transport equipment that efficiently moves people or goods between floors (levels, decks) of a building, vessel or other structures.Powered by Electric Motors

• Escalator
• Elevator
• Conveyor
• Chutes

The state of Refrigerant at point D is ........

• Liquid
• Mixture (Liquid +Vapor)
• Vapor

2. What is the minimum size THW copper conductor that may be used on a 30-ampere branch circuit?

• No. 14 AWG
• No. 12 AWG
• No. 10 AWG
• No. 8 AWG

28. Feeders containing a common neutral are permitted to supply how many sets of 4-wire feeders?

• 2
• 3
• 4
• 5

13. Cable tray systems must not be used:

• For power and control applications
• For service-entrance systems
• For signal cables
• In hoistways

The state of Refrigerant at point C is ........

• Liquid
• Vapor
• Mixture (Liquid + Vapor )

26. The lighting outlets installed at or near heating, air-conditioning, and refrigeration equipment in attics or underfloor spaces be controlled by a switch. Where must the switch be located?

• Mounted on the HVAC equipment
• At the point of entry to the area
• At the main disconnect
• At least 5 feet from the equipment

The rated speed Of Escalators shall be not more than 0.64 m/s except that higher speeds may be permitted subject to the approval of the enforcing authority.

• 0.61 m/s
• 0.62 m/s
• 0.63 m/s
• 0.64 m/s

42. What is the minimum size conductor allowed for festoon lighting?

• No. 8 AWG
• No. 10 AWG
• No. 12 AWG
• No. 14 AWG

The effective temperature increases with a decrease in relative humidity at the same DBT.

• True
• False

- any of the various designs of fittings that allow service tools such as manifold gauges to be attached to an A/C system.

• A/C lines
• valve stem
• service port
• receiver/dryer

21. In what location must a 125-volt single-phase, 15- or 20-ampere receptacle be installed for the servicing of heating, air conditioning and refrigeration equipment?

• All apartment buildings
• One- and two-family dwellings
• Commercial buildings
• All locations

When the heat stored in the body is ________ the human body feels comfortable.

• zero
• infinite
• positive
• negative

36. If four 12 kW electric ranges are used in a four-unit apartment complex, what is the total kW rating that must be used for all of these ranges in calculating the electric service?

• 17 kW
• 18 kW
• 20 kW
• 48 kW

When leaving the compressor what state is the refrigerant in?

• High Pressure, High Temperature gas
• High Pressure, High Temperature liquid
• Low Pressure, low Temperature gas

The air conditioning compressor _____________ vaporized refrigerant and allows it to flow to the condenser.

• pressurizes
• cools
• supplies
• cleans

When the hospital elevator can be made accessible at any other level which is accessible by means of an elevator with a minimum width of ____ mm

• 600 mm
• 700mm
• 800 mm
• 900 mm

1. The cross-sectional area of three or more THW conductors ina conduit must not exceed what percent of the cross-sectional areaof the conduit?

• 30%
• 40%
• 50%
• 60%

Most escalator are designed with ____ mm wide steps which allow passengers to move comfortably when carrying luggage and shopping bags

• 500 mm
• 1000 mm
• 1500 mm
• 2000 mm

38. What demand factor is allowed for a commercial kitchen with one electric appliance?

• 65%
• 70%
• 80%
• 100%

- a heat exchanger, in which low-pressure refrigerant flows and changes state, absorbing heat from the surrounding air and cools the passenger compartment.

• compressor
• condenser
• receiver/dryer
• evaporator

Automatic centralized control of a building's HVAC and otherinterrelated system.

4. What is the maximum continuous load (in amperes) that can be used on a 240-volt, 20- ampere circuit using two No. 12 AWG conductors with THW insulation?

• 12 amperes
• 15 amperes
• 16 amperes
• 20 amperes

How could you confirm the type ofrefrigerant present in an air conditioning system?

• The odour the refrigerant emitswhen released to atmosphere
• The colour of the refrigerant whichis visible through the sight glass in the top of the receiver drier
• Bychecking the identifier label located on the vehicle
• It does not matter as R12 and R134aare interchangeable

3. Heavy-duty type lampholders are required on branch-circuits having a rating in excess of:

• 20 amperes
• 30 amperes
• 40 amperes
• 15 amperes

34. What is the minimum load per each linear foot that must be allowed for show-window lighting?

• 100 volt-amperes
• 200 volt-amperes
• 300 volt-amperes
• 400 volt-amperes

45. Receptacles and cord connectors that have equipment grounding conductor contacts must have those contacts:

• Energized
• Connected to an equipment grounding conductor
• Polished and free from corrosion
• Checked monthly

In the evaporator, refrigerant is under very low pressure and is much colder than the air inside of the vehicle. Because of this, heat transfers from the ________ to the _______, causing the refrigerant to _______.

• refrigerant, vehicle, vaporize
• vehicle, refrigerant, condense
• vehicle, refrigerant, vaporize
• refrigerant, vehicle, condense

15. The total equivalent bend in rigid conduit between pull points (outlet to outlet, fitting to fitting, or outlet to fitting) shall not exceed:

• 3 quarter bends (270°)
• 4 quarter bends (360°)
• 5 quarter bends (450°)
• 6 quarter bends (540°)

What do you call the part of a refrigeration system in which the refrigerant absorbs heat and changes from a liquid to a gas.

• condenser
• evaporator
• expansion valve
• radiator

24. How many lighting outlets must be installed at or near heating, air-conditioning, and refrigeration equipment in attics or underfloor spaces?

• 1
• 2
• 3
• 4

What is the value of the optimum effective temperature in summer?

• 23
• 22
• 21
• 24

What are the impacts on the environmentof fluorinated greenhouse gases?

• Contributes to the formulation of acidrain
• Contributes to the global warming
• Mixes with the Nitrogen within theatmosphere to create a toxic substance, Nox
• Has little or no detrimental effect

6. Branch circuits in two-family or multifamily dwellings required for the purpose of central lighting, central alarm, signal, communications, or other needs for public or commercial areas shall:

• Be rated over 30 amperes for any application or purpose
• Terminate in one of the dwelling unit’s panelbaord
• Be rated over 50 amperes
• Not be supplied from a dwelling unit’s panelboard

How would you know the air con gas hasbeen fully recovered from the system?

• The gauge on the high pressure sidereads a positive pressure
• The gauge on the low pressure sidereads a negative pressure
• Bothgauges read zero pressure at the end of the recovery process
• Both gauges read a positivepressure of 20 Bar at the end of the recovery process

a valve that controls the flow of refrigerant, changing it from a high pressure liquid to a low pressure gas

• service port
• expansion valve
• A/C lines
• evaporator

22. A 125-volt single-phase, 15- or 20-ampere receptacle be installed for the servicing of heating, air conditioning and refrigeration equipment must be installed within what distance from the equipment?

• 25 feet
• 50 feet
• 75 feet
• 100 feet

- an A/C system component into which high-pressure liquid refrigerant flows and is temporarily stored and dehydrated, usually located between the condenser outlet and expansion valve.

• compressor
• receiver/dryer
• accumulator
• evaporator

11. Holes in wood studs for cables must be drilled in the center of the stud and a distance from the nearest edge of not less than:

• 1/2 inch
• 1 inch
• 1 & 1/4 inches
• 1 & 1/2 inches

What is the job of the condenser?

• Create flash gas, superheat, cool refrigerant
• subcool, superheat, condense refrigerant
• meter refrigerant, create flash gas, condense
• desuperheat, condense, subcool refrigerant

a device, similar to a radiator, in which the refrigerant loses heat and changes state from a high-pressure gas to a high-pressure liquid as it dissipates heat to the surrounding air.

• condenser
• compressor
• evaporator
• radiator

In what state is the refrigerant when it exits the condenser?

• High pressure gas
• Low pressure gas
• High pressure liquid
• Low pressure liquid

The elevators require regular inspection and maintenance and generally have a life of _____ years.

• 5 years
• 10 years
• 15 years
• 20 years

12. Direct buried conductors and cables emerging from grade shall be protected by an enclosure or raceway a distance above ground of no less than:

• 6 feet
• 8 feet
• 10 feet
• 12 feet

Which component squeezes the gas?

• Compressor
• Condenser
• Evaporator
• Thermal Xpansion Valve

Most common type of elevator. Elevator cars are pulled by means of rolling steel ropes over a deeply grooved pulley also called sheave.

What is the temperature of the liquid line if you touch it?

• Warm
• Cold
• Cool
• Very Warm/Hot

23. A 125-volt single-phase, 15- or 20-ampere receptacle be installed for the servicing of heating, air conditioning and refrigeration equipment. The receptacle outlet shall not be connected to the ___ side of the equipment disconnecting means

• On the line side
• At the equipment controls
• On the load side
• At the main panelboard

are the moving step type lifts operating at constant speed between two levels in an inclined course for moving large number of people in a short time

• Stairs
• Elevator
• Escalator
• Conveyor

What is the compressor known as?

• The heart of the system.
• The leg of the system.
• The control system.
• The air system.

Where would you expect to find a high pressure liquid within an AC system?

• Between the compressor and the Thermal Xpansion Valve
• Between the Thermal Xpansion Valve and the Evaporator
• Between the compressor and the condenser
• Between the Condenser and the Thermal Xpansion Valve

50. Which one of the following is not allowed to supply branch circuits?

• A 277-volt circuit
• A 120-volt circuit
• Autotransformer if the circuit is without a grounded conductor of the required type
• A buck-and-boost transformer

What is the temperature of the discharge line if you touch it.

• Warm
• Cool
• Cold
• Very Warm/Hot

In a typical system, within whichcomponent would the evaporation of refrigerant take place?

• Condenser
• Receiver dryer
• Evaporator
• Compressor

What is the state of the refrigerant leaving the evaporator?

• 100 percent liquid
• 50 percent liquid and 50 percent vapor
• 100 percent superheated vapor
• 100 percent subcooled liquid

What happens in the first 1/3 of the condenser?

• Refrigerant subcools
• Refrigerant superheats
• Refrigerant changes to 25 percent vapor and 75 percent liquid
• Refrigerant desuperheats

19. How many receptacles are required in a residential hallway 12 feet in length?

• 1
• 2
• 3
• 4

27. Feeders containing a common neutral are permitted to supply how many sets of 3-wire feeders?

• 1 or 2
• 5 or 6
• 3 or 4
• 2 or 3

- to remove refrigerant from an A/C system and store it temporarily.

• refrigerant recovery
• coolant recovery
• recharge
• vacuum

8. All 125-volt, single-phase, 15- or 20-ampere receptacle outlets installed in bathrooms of dwelling units always require:

• Twist-lock receptacles
• Ground-fault circuit-interrupter (GFCI) protection
• Non-grounded receptacles
• Waterproof receptacle covers

What type of refrigerant is R134a?

• CFC
• HCFC
• HSBC
• HFC

Which of the following does not mainly a factor of dependency for the degree of warmth or cold?

• Relative humidity
• WBT
• Air velocity
• DBT

These lifts are self-contained and can be easily moved to where they are needed.

37. If the apartment complex is expanded to include a total of 40 units with a 12 kW range in each, what is the total kW rating for all the ranges that must be used in calculating the electric service?

• 45 kW
• 50 kW
• 55 kW
• 60 kW

The main components of the Air conditioning system are

• Thermistor, condenser, flow control and an evaporator.
• Fan blower, condenser, flow control and an evaporator.
• Compressor, condenser, TXV and an evaporator.
• Drainage, condenser, flow control and an evaporator.

This removes pressure from the liquid refrigerant to allow expansion or change of state from a liquid to a vapor in the evaporator

• condenser
• evaporator
• expansion valve
• radiator

Escalator Inspection are required once a year.

• TRUE
• FALSE

25. How are the lighting outlets installed at or near heating, air-conditioning, and refrigeration equipment in attics or underfloor spaces be controlled?

• From the load side of the HVAC equipment
• With a motor control
• By a switch
• With a 30-amp safety switch

a compound typically found in either a fluid or gaseous state. It readily absorbs heat from the environment and can provide refrigeration or air conditioning when combined with other components such as compressors and evaporators.

• Green Gases
• Refrigerant
• Condenser
• Foam

40. When outside overhead wiring is used, with no messenger cable, what is the minimum size aluminum wire allowed for spans up to 50 feet?

• No. 6 AWG
• No. 8 AWG
• No. 10 AWG
• No. 12 AWG

47. When existing nongrounding types of receptacles need replacing, what type of receptacle must be used?

• Receptacles rated for at least 15 amperes
• Receptacles rated for at least 20 amperes
• Twist-lock receptacles
• Grounding-type receptacles

33. Where a feeder conductor supplies continuous loads, the rating of the overcurrent device shall not be less than the noncontinuous load plus 125% percent of the continuous load except?

• Where the overcurrent devices are listed for operation at 100%
• Where the overcurrent devices are listed at 75%
• Where the overcurrent devices are listed at 80%
• Where no overcurrent devices are provided

Adding pressure to a liquid _______ its boiling point. Adding pressure to a vapor _______ its temperature.

• raises, raises
• lowers, lowers
• raises, lowers
• lowers, raises

- a chemical compound used in an A/C system to remove heat from the evaporator and transfer it to the condenser.

• refrigerant
• coolant
• hydraulic oil
• anti-freeze

29. Feeders containing a common neutral are permitted to supply how many sets of 5-wire feeders

• 1
• 2
• 3
• 4

What does MAC stand for?

• MobileAir Conditioning
• Mechanical Air Conditioning
• Mobile Air Compressor
• Mechanical Air Compressor

The heat production from a normal healthy man when asleep is about _________

• 50 W
• 40 W
• 70 W
• 60 W

If contamination within an air conditioning system is suspected and a flushing procedure is to be carried out what component should also be changed?

• Compressor
• Receiver Drier
• Thermal Xpansion Valve
• Condenser

7. EMT must be supported within what distance from an outlet box, junction box, device box, cabinet, conduit body or other terminations?

• 3 feet
• 4 feet
• 5 feet
• 6 feet

18. A 20-ampere laundry circuit is always required in each:

• Industrial wash room
• Commercial utility room
• Dwelling unit
• Motel unit

What does COSHH stand for?

• Control of Substances Hazardous tohealth
• Company omissions of safe Health hazards
• Control of solutions hazardous to health
• Control of Substances which are health hazardous

20. How many receptacle outlets are required in a residential garage?

• 4
• 3
• 2
• 1

The name of part No (3) is...........

• Evaporator
• Capillary tube
• Compressor

Which of the following provides the relationship between the optimum indoor effective temperature and optimum outdoor effective temperature?

• Clothing
• Occupants
• Duration of stay
• Climatic and seasonal differences

The machine room and the escalator hoistway shall be finished with mortar or other materials so as to prevent concrete dust.

• TRUE
• FALSE

17. The branch-circuit load for a single 12-kilowatt (12 kW) electric range in a dwelling is:

• 8kW
• 9kW
• 10kW
• 11kW