Air Conditioning and Refrigeration Service

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

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%

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

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

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

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

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

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

- 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

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

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

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

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

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

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

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

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

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

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

• Green
• Light blue
• White

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

• Evaporator
• Capillary tube
• Compressor

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

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

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

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%

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

• zero
• infinite
• positive
• negative

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

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

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

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

• True
• False

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

• Sensor
• Cloud
• Camera
• Hardisk

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

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.

An electric motor shall not drive more than _____ escalator.

• one
• two
• three
• four

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

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

Which system has moving parts?

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

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

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

• pressurizes
• cools
• supplies
• cleans

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

What type of refrigerant is R134a?

• CFC
• HCFC
• HSBC
• HFC

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

• 4
• 3
• 2
• 1

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

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

• refrigerant recovery
• coolant recovery
• recharge
• vacuum

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

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

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

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

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

• Mixture (vapor + liquid)
• vapor
• Liquid

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%

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

• 2
• 3
• 4
• 5

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

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

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

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

• Relative humidity
• WBT
• Air velocity
• DBT

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

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

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

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

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

• Warm
• Cold
• Cool
• Very Warm/Hot

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

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

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

• Liquid
• Vapor
• Mixture ( liquid + vapor)

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

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

• 65%
• 70%
• 80%
• 100%

Which component squeezes the gas?

• Compressor
• Condenser
• Evaporator
• Thermal Xpansion Valve

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

• Warm
• Cool
• Cold
• Very Warm/Hot

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

• Liquid
• Vapor
• Mixture (Liquid + Vapor )

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

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

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

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

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

• Condenser
• Receiver dryer
• Evaporator
• Compressor

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

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

• Liquid
• Mixture (Liquid +Vapor)
• Vapor

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

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

• air conditioning
• condensation
• evaporation
• refrigeration

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

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

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.

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

• 8kW
• 9kW
• 10kW
• 11kW

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

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

- 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

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°)

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

• 50 W
• 40 W
• 70 W
• 60 W

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

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

• Compressor
• Condenser
• Capillary tube

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

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

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

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

14. EMT shall be supported at least every:

• 4 feet
• 8 feet
• 10 feet
• 15 feet

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

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

• Warm
• Cold
• Cool
• Very Warm/Hot

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

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

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

- 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

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

• TRUE
• FALSE

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

Where does the low pressure liquid become a gas?

• Evaporator
• Condenser
• TX valve
• Compressor

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

• 1
• 2
• 3
• 4

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

Escalator Inspection are required once a year.

• TRUE
• FALSE

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

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

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

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

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 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

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

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

The Simple Refrigeration cycle consists of .....

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

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

• Condenser
• Evaporator
• Compressor

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

- 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

13. Cable tray systems must not be used:

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

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%

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 does MAC stand for?

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

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

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

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

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

• Warm
• Cold
• Cool
• Very Warm/Hot

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

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

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

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

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 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

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

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

What is the value of optimum effective temperature in winter?

• 17
• 18
• 19
• 20

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

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

• Condenser
• Capillary tube
• Evaporator

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

• 1
• 2
• 3
• 4

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

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

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

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

• R1234yf
• R12
• R134a
• R2D2

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

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

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

• 23
• 22
• 21
• 24

What is the compressor known as?

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

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

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

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

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