Book 2: 4-19 - "Heat Exchangers for Refrigeration Systems"

Question 1

Based on how they operate one of the basic types of evaporator is the _____ evaporator.
Select one:

A. Dry/direct expansion

B. Evaporative

C. Aerial

D. Cold expansion

E. Dry/indirect expansion

Answer 1

A. Dry/direct expansion

Question 2

The finned tube evaporator is basically a bare tube evaporator coil with fins attached to it by crimping or bonding to form a/an:
Select one:

A. Decreased temperature exchange surface area

B. Decreased heat exchange surface area

C. Increased heat exchange surface area

D. Increased temperature exchange surface area

E. Increased heat exchange volume

Answer 2

C. Increased heat exchange surface area

Question 3

Evaporative condensers continual evaporation of water and its replenishment from the makeup supply causes the concentration of dissolved solids steadily increases in the water and if uncontrolled would eventually:
Select one:

A. Precipitate out as mud

B. Condense out as scale

C. Condense out as mud

D. Precipitate out as scale

E. Evaporate out as scale

Answer 3

D. Precipitate out as scale

Question 4

A proper chemical treatment program for evaporative condensers includes a/an:
Select one:

A. Oxygen scavenger

B. Scale producer

C. Sludge conditioner

D. Anti-foaming agent to prevent turbulence from creating foam in the sump

E. Precipitation agent

Answer 4

D. Anti-foaming agent to prevent turbulence from creating foam in the sump

Question 5

The plate surface evaporator is usually applied as a _____ evaporator.
Select one:

A. Evaporative

B. Dry/direct expansion

C. Flooded

D. Cold expansion

E. Aerial

Answer 5

B. Dry/direct expansion

Question 6

A double tube condenser consists of a:
Select one:

A. Small tube wound around a larger tube

B. Small tube parallel to a larger tube

C. Large tube contained concentrically within a smaller tube

D. Small tube contained concentrically within a larger tube

E. Large tube wound around a smaller tube

Answer 6

D. Small tube contained concentrically within a larger tube

Question 7

Defective condenser operation in the compression refrigeration system may result from:
Select one:

A. Dirty refrigerant

B. Dirty cooling water on the refrigerant side surface of the coils

C. Dirty cooling water on the waterside surface of the coils

D. Dirty refrigerant on the cooling surface of the coils

E. Dirty refrigerant on the waterside surface of the coils

Answer 7

C. Dirty cooling water on the waterside surface of the coils

Question 8

One of the basic designs of water-cooled condensers is the _____ condenser:
Select one:

A. Direct expansion

B. Bare tube

C. Shell and coil

D. Evaporative

E. Flooded

Answer 8

C. Shell and coil

Question 9

Evaporative condensers are favored in locations where it is necessary to conserve on:
Select one:

A. Power

B. Air

C. Noise

D. Space

E. Water

Answer 9

E. Water

Question 10

The shell and tube evaporator is also known as a:
Select one:

A. Heat exchanger

B. Condenser

C. Evaporator

D. Cooler

E. Chiller

Answer 10

E. Chiller

Question 11

The additional heat added by the compressor results in the condenser being _____ larger in capacity than the evaporator.
Select one:

A. 15% to 20%

B. 20% to 25%

C. 25% to 30%

D. 10% to 15%

E. 5% to 10%

Answer 11

A. 15% to 20%

Question 12

According to their class of construction one of the refrigeration evaporators is the _____ evaporator.
Select one:

A. Water tube

B. Flat tube

C. Bare tube

D. Condensing

E. Square tube

Answer 12

C. Bare tube

Question 13

A proper chemical treatment program for evaporative condensers includes a/an:
Select one:

A. Oxygen scavenger

B. Precipitation agent

C. Scale producer

D. Sludge conditioner

E. Biocide to prevent bacteria buildup due to the warm water

Answer 13

E. Biocide to prevent bacteria buildup due to the warm water

Question 14

One of the basic designs of water-cooled condensers is the _____ condenser:
Select one:

A. Flooded

B. Evaporative

C. Direct expansion

D. Bare tube

E. Shell and tube

Answer 14

E. Shell and tube

Question 15

The refrigeration condenser must remove _____ absorbed in the evaporator, along with the heat of compression added to the refrigerant by the compressor.
Select one:

A. Both the temperature and pressure

B. Both the latent and sensible heat

C. The enthalpy and entropy

D. The sensible heat

E. The latent heat

Answer 15

B. Both the latent and sensible heat

Question 16

One of the main heat exchangers used in the compression refrigeration system is the:
Select one:

A. Cooling tower

B. Compressor

C. Condenser

D. Regenerator

E. Absorber

Answer 16

C. Condenser

Question 17

A serious reduction in the rate of heat transfer through the condenser surfaces will occur if _____ are permitted to accumulate on the refrigerant-side surfaces of the tubes or coils.
Select one:

A. Refrigerant deposits

B. Refrigerants

C. Coolants

D. Non-condensables

E. Lubricating oil deposits

Answer 17

E. Lubricating oil deposits

Question 18

An evaporator is that part of the refrigerating system in which the _____ by the absorption of heat from the medium to be cooled.
Select one:

A. Liquid refrigerant is condensed

B. Vapour refrigerant is condensed

C. Vapour refrigerant is liquidized

D. Vapour refrigerant is vaporized

E. Liquid refrigerant is vaporized

Answer 18

E. Liquid refrigerant is vaporized

Question 19

Bare tube evaporators are used when the space temperature is maintained below :
Select one:

A. 20°C (68°F)

B. 10°C (50°F)

C. 5°C (41°F)

D. 15°C (59°F)

E. 1°C (34°F)

Answer 19

E. 1°C (34°F)

Question 20

One of the basic designs of water-cooled condensers is the _____ condenser:
Select one:

A. Evaporative

B. Flooded

C. Direct expansion

D. Double tube

E. Bare tube

Answer 20

D. Double tube