quiz 2

Question 1

Which device is used to check a leak in an ammonia system?

Answer 1

Halide torch

Other options include litmus paper and sulfur stick.

Question 2

What color smoke does a sulfur stick produce in the presence of ammonia?

Answer 2

Dense white smoke.

Question 3

An ammonia leak will turn litmus paper _______.

Answer 3

blue.

Question 4

In an ammonia system, the oil gauge must be kept _______.

Answer 4

closed except when checking oil level.

Question 5

Valves and piping in an ammonia system are made of _______.

Answer 5

iron.

Question 6

The relief valve on an ammonia machine is located _______.

Answer 6

on the discharge pipe from the compressor.

Question 7

When purging an ammonia condenser into a bucket of water, how can one tell when ammonia starts to come through?

Answer 7

By the smell of the ammonia being liberated from the water.

Question 8

The crossover connection in an ammonia system can be used for _______.

Answer 8

hot-gas defrost.

Question 9

How is an ammonia system purged to avoid operator exposure to fumes?

Answer 9

Into a bucket of water.

Question 10

Thermal expansion valves are usually of the _______.

Answer 10

diaphragm.

Question 11

When checking zinc plates in a condenser, one should _______.

Answer 11

clean the plates and renew worn out ones.

Question 12

The scale trap is located between the _______.

Answer 12

King (liquid) valve and expansion valve.

Question 13

When the evaporator coils are located in the icebox, the system is known as a _______.

Answer 13

direct system.

Question 14

The purge valve is located _______.

Answer 14

in the highest part of the system.

Question 15

The solenoid valve is a _______.

Answer 15

temperature-controlled stop valve.

Question 16

The thermal expansion valve is located between the _______.

Answer 16

solenoid valve and the evaporator coils.

Question 17

The purpose of the scale trap is to _______.

Answer 17

remove dirt, scale and metal chips from the refrigerant.

Question 18

The oil separator (trap) is located between the _______.

Answer 18

compressor discharge valve and the condenser.

Question 19

The charging connection in a refrigerating system is located _______.

Answer 19

between the king valve and the solenoid valve.

Question 20

The dehydrator is located _______.

Answer 20

between the receiver and the expansion valve.

Question 21

The charging valve is located between the _______.

Answer 21

king valve and the expansion valve.

Question 22

The solenoid valve is located between the _______.

Answer 22

thermal expansion valve and the evaporator.

Question 23

A device used to keep moisture from passing through the system is called a _______.

Answer 23

dehydrator.

Question 24

The relief valve is located on the _______.

Answer 24

discharge side of the compressor.

Question 25

The dehydrator is used to _______.

Answer 25

remove moisture from the system.

Question 26

Which of the following is another name for the liquid valve?

Answer 26

King valve.

Question 27

If no gaskets are used in the piping joints of a Freon system, the _______.

Answer 27

wielded joints.

Question 28

A device for holding open the suction valve and drawing gas from the suction manifold is called a _______.

Answer 28

cylinder unloader.

Question 29

The solenoid valve can be typed as a _______.

Answer 29

magnetic stop valve.

Question 30

The bulb for the thermal expansion valve is located _______.

Answer 30

near the evaporator coil outlet.

Question 31

The elements of a thermostat switch are usually of the _______.

Answer 31

bimetal type.

Question 32

The expansion valve is located between the _______.

Answer 32

receiver and evaporator.

Question 33

The oil separator is located between the _______.

Answer 33

compressor and condenser.

Question 34

Zinc rods are found in the _______.

Answer 34

salt-water side of condenser.

Question 35

A double-trunk piston is used to _______.

Answer 35

prevent gas from getting to crankcase.

Question 36

Which gasket materials should be used on a Freon system?

Answer 36

A and B.

Question 37

Many pressure gauges on a Freon system have two dials representing _______.

Answer 37

suction and discharge pressure.

Question 38

A double-pipe condenser has _______.

Answer 38

a small pipe inside a larger pipe.

Question 39

When there is a Freon leak, the torch will burn _______.

Answer 39

green.

Question 40

Large leaks in a Freon system can be detected easier by applying _______.

Answer 40

a soapsuds solution.

Question 41

The relief valve on a CO2 Machine is located _______.

Answer 41

on the discharge pipe between the compressor and the discharge valve.

Question 42

The discharge pressure of the compressor should be _______.

Answer 42

the pressure which corresponds to a temperature from 5°F to 15°F higher than the condenser discharge.

Question 43

The purpose of relief valves on refrigeration machines is to _______.

Answer 43

prevent excessive pressure in case of stoppage on the discharge side of the system.

Question 44

A leaky suction valve can usually be detected by _______.

Answer 44

any of these.

Question 45

Too low suction pressure could be caused by _______.

Answer 45

any of these.

Question 46

What do you call a system in which the evaporator coils are located in a brine solution?

Answer 46

an indirect system.

Question 47

Before securing a compressor for maintenance, be sure to _______.

Answer 47

pump down the system.

Question 48

Obstruction of the valve is usually caused by _______.

Answer 48

any of these.

Question 49

Excess frost on the evaporator coils _______.

Answer 49

reduces efficiency of the plant.