ammonia exam

Question 1

Calcium chloride brine solutions are suitable for food processing applications because it uses simple table salt in mixture (t or f)

Answer 1

f

Question 2

when using an electric float for the control of ammonia systems a needle valve must always be used to control the amount of liquid refrigerant entering the chiller, this valve is normally located up stream of the liquid solonoid valve (t or f)

Answer 2

t

Question 3

calcium chloride may be stored in the same location or equipment room as ammonia as long as there is no direct source of heat (t or f)

Answer 3

f

Question 4

copper or brass may be used in ammonia systems as long as there is no moisture present in the equipment room (t or f)

Answer 4

f

Question 5

the minimum test pressure for the lowside of an air cooled ammonia system is equal to or greater than the setting of the pressure relief device (t or f)

Answer 5

f

Question 6

cascade is desirable if system temperatures of lower than -125 are required

Answer 6

t

Question 7

the liquid recirculating pump as used with 2 stage liquid recirculation ammonia systems is located between

Answer 7

The low pressure receiver and the evaporator

Question 8

the boiling point of r717 at atmospheric pressure is

Answer 8

-28f

Question 9

when installing globe valves in any system for component isolation how should they be installed on horizontal line rows

Answer 9

the stem should be at right angles to a horizontal run of pipe and the high pressure side exerted on the bottom side of seat assembly

Question 10

what component is not normally required in cascade systems

Answer 10

low stage condenser

Question 11

which type of intercooler is not suitable for ammonia compression systems

Answer 11

dry type

Question 12

multi stage or booster compression systems are normally required for low temp applications such as ammonia blast freezers. This type of compression system is normally good for applications above -90f and should be used if the reciprocating compression ratio of a single stage system exceeds

Answer 12

10;1

Question 13

multi stage compression systems can be put in 2 groups

Answer 13

cascade or direct

Question 14

ammonia receiver 3ft x 60’’ long what is the prv capacity

Answer 14

7.5 lbs per min

Question 15

the corrosiveness of a brine or eutectic mixture should be maintained between _ and _ and can be determined by a ph tester

Answer 15

7-8.5

Question 16

the normal temp drop through a lower temp chiller is normally

Answer 16

2f at a flow rate of 10 to 15 gallons per ton

Question 17

normally ice temp is controlled by a brine thermostat if your sat suction temp is 8f what should your actual ice temp be

Answer 17

28f

Question 18

centrifugal pumps are widely used in the industry what device can be found in the stuffing box of a centrifugal pump that has no moving parts

Answer 18

packing gland

Question 19

1 closed circuit condenser water is not exposed to atmosphere
2 direct contact condenser water is not exposed to atmosphere
3 closed circuit condenser water is exposed to atmosphere
4 direct contact condenser water is exposed to atmosphere

Answer 19

1&4

Question 20

what is the importance of the fill material as used in cooling tower design and construction

Answer 20

fill adds to the surface area of the cooling tower

Question 21

2 types of fill material used

Answer 21

cedar strips and polyvinylchloride

Question 22

term used for a mixture of salt and water to lower its freezing temp below 32f

Answer 22

eutectic mixture

Question 23

under what condition should the operator or service tech wear a self contained breathing apparatus into an ammonia equipment room

Answer 23

300 ppm

Question 24

most common sec refrigerant

Answer 24

water

Question 25

what is particular code requirement with regards to the construction of a fire valve box for a class t machinery room

Answer 25

it has a glass front

Question 26

term used to describe the constant dilution of cooling tower sump water

Answer 26

bleed water

Question 27

a microprocessor controller analyzes the conductivity of the cooling tower sump water when the electrical conductivity is high what maintenance must be performed

Answer 27

indicates that the water is contaminated and must be drained and refilled

Question 28

the liquid leaving the pipe on the discharge side of the system is the

Answer 28

point of free discharge

Question 29

feet

Answer 29

head unit measurement

Question 30

the head that appears only when the liquid is moving

Answer 30

friction head

Question 31

the normal type of pump used in the industry

Answer 31

centrifugal pump

Question 32

liquid entering the pump with the level below the center line of the pump

Answer 32

static suction lift

Question 33

liquid entering the suction side of the pump

Answer 33

lift or head

Question 34

the pressure that the pump must overcome on the discharge

Answer 34

total static head

Question 35

pressure + velocity + friction heads

Answer 35

dynamic head

Question 36

the head that is measured only when the pump is off

Answer 36

static head

Question 37

dynamic + total static

Answer 37

total head

Question 38

3 main groups of sec refrigerants

Answer 38

brines, glycol, alcohol

Question 39

according to b52 indentify 6 design features that are required for an ammonia equipment room

Answer 39

b52 6.3

Question 40

2 methods of demhumidification for curling or ice rinks

Answer 40

ventilation fans refrigerated dehumidifier

Question 41

where should the fire valve be located on class t ammonia equipment room

Answer 41

7.5 feet off ground

Question 42

under what condition should a operator wear an escape breathing respirator into an ammonia equipment room

Answer 42

incase of a sudden leak in the system