Book 2: Unit 4 - Review:

Question 1

The applicable code requires that each refrigerating system containing _____ or more of Group A1 refrigerant having an operating pressure over 103 kPa shall be constructed so the refrigerant can be discharged into the atmosphere by means of a manually operated valve to be used in case of emergency.
Select one:

A. 45.0 kg (100 lb)

B. 182.0 kg (400 lb)

C. 91.0 kg (200 lb)

D. 273.0 kg (600 lb)

E. 136.0 kg (300 lb)

Answer 1

A. 45.0 kg (100 lb)

Question 2

The moisture indicator and sight glass in a compression refrigeration system is placed between the:
Select one:

A. Compressor and the evaporator

B. Condenser and the receiver

C. Compressor and the condenser

D. Receiver and the expansion valve

E. Expansion valve and the evaporator

Answer 2

D. Receiver and the expansion valve

Question 3

The compression ratio is calculated by dividing the:
Select one:

A. Discharge gauge pressure by the Suction gauge pressure

B. Absolute discharge pressure by the absolute suction pressure

C. Absolute discharge pressure by the suction gauge pressure

D. Absolute suction pressure by the absolute discharge pressure

E. Discharge gauge pressure by the absolute suction pressure

Answer 3

B. Absolute discharge pressure by the absolute suction pressure

Question 4

One of the general types of condensers is the _____ condenser.
Select one:

A. Direct expansion

B. Water-cooled

C. Bare tube

D. Flooded

E. Dry

Answer 4

B. Water-cooled

Question 5

The air handling unit may include all except a/an:
Select one:

A. Motorized dampers for airflow control

B. Filters

C. Source of heating and cooling

D. Air sanitizer

E. Fan

Answer 5

D. Air sanitizer

Question 6

Liquid refrigerants are fluids that, at atmospheric pressure, have a boiling point considerably:
Select one:

A. Lower than that of oxygen

B. Lower than that of water

C. Lower than that of oil

D. High than that of water

E. Higher than that of oxygen

Answer 6

B. Lower than that of water

Question 7

The main parts of a refrigerant reciprocating compressor include all except the:
Select one:

A. Compressor bearings

B. Suction and discharge valves

C. Compressor body

D. Pistons and connecting rods

E. Blades

Answer 7

E. Blades

Question 8

One of the main classifications of refrigeration compressors is the _____ compressor.
Select one:

A. Piston

B. Vane

C. Axial

D. Screw

E. Centrifugal

Answer 8

E. Centrifugal

Question 9

Refrigerants that are flammable and highly toxic belong to Group:
Select one:

A. A3

B. B3

C. A2

D. B1

E. B2

Answer 9

E. B2

Question 10

Steel refrigeration piping of schedule 40 may be used when the diameter over:
Select one:

A. 25 mm (1 in)

B. 19 mm (¾ in)

C. 38 mm (1½ in)

D. 13 mm (½ in)

E. 32 mm (1¼ in)

Answer 10

A. 25 mm (1 in)

Question 11

The fusible plug relief device consists of a connection filled with a metal alloy designed to:
Select one:

A. Melt at a specific pressure

B. Freeze at a specific pressure

C. Freeze at a specific temperature

D. Vaporize at a specific temperature

E. Melt at a specific temperature

Answer 11

E. Melt at a specific temperature

Question 12

The high pressure in the condenser is maintained by the:
Select one:

A. Receiver

B. Expansion valve

C. Evaporator

D. Chiller

E. Compressor

Answer 12

E. Compressor

Question 13

In the compression refrigeration system to condense the low-pressure, low-temperature vapour back to a liquid the _____ absorbed in the evaporator must be removed.
Select one:

A. Sensible temperature

B. Latent heat

C. Sensible heat

D. Latent temperature

E. Enthalpy

Answer 13

B. Latent heat

Question 14

If a compressor discharge pressure gauge indicates 1120 kPa and the suction pressure is 70 kPa , what is the pressure ratio?
Select one:

A. 7.25

B. 16

C. 3.84

D. 16.2

E. 7.14

Answer 14

E. 7.14

Question 15

The function an air conditioning system that provides a source of heat to offset the heat loss to the atmosphere surrounding the building through the exterior walls and roof and through floor slabs on grade and basement walls is:
Select one:

A. Ventilation

B. Humidification

C. Filtration

D. Heating

E. Cooling

Answer 15

D. Heating

Question 16

The induced draft cooling tower has one or more fans located at the top of the tower that _____ the downward flow of water.
Select one:

A. Draw water upwards against

B. Draw air upwards with

C. Draw air upwards against

D. Draw water upwards with

E. Draw air downwards against

Answer 16

C. Draw air upwards against

Question 17

One of the functions of the compressor in a refrigeration system is to raise the _____ pressure and temperature.
Select one:

A. High-temperature, low-pressure vapours

B. High-temperature, low-pressure liquids

C. Low-temperature, low-pressure liquids

D. Low-temperature, high-pressure vapours

E. Low-temperature, low-pressure vapours

Answer 17

E. Low-temperature, low-pressure vapours

Question 18

The rotary design of refrigeration compressors includes all of the following except:
Select one:

A. Helical rotor

B. Rotating vane

C. Helical screw

D. Stationary single-blade

E. Piston

Answer 18

E. Piston

Question 19

The counterflow mechanical draft tower occupies less floor space than a crossflow tower but is _____ for a given capacity.
Select one:

A. Faster

B. Smaller

C. Larger

D. Shorter

E. Taller

Answer 19

E. Taller

Question 20

The applicable code specifies that when a system contains more than _____ of refrigerant, stop valves are required on the suction and discharge of each compressor, compressor unit, or condensing unit and on the outlet of each liquid receiver.
Select one:

A. 10.0 kg (22 lb)

B. 5.0 kg (11 lb)

C. 3.0 kg (6.6 lb)

D. 1.0 kg (2.2 lb)

E. 8.0 kg (17.6 lb)

Answer 20

C. 3.0 kg (6.6 lb)