Epa Type Iii

Front 1

A typical setting for the high pressure cut-out control on a recovery unit used for evacuating the refrigerant from a low pressure chiller is:

Back 1

10 PSIG

Front 2

A charged low pressure refrigeration system can be efficiently leak checked by:

Back 2

Raising system pressure by heating with circulated hot water or heating blankets.

Front 3

The existence of air in a low pressure system, causes _______

Back 3

High head pressure

Front 4

Which safety precaution should be adhered to for low pressure systems?

Back 4

Do not siphon refrigerant by mouth, avoid spilling liquid refrigerant on the skin, use gloves and safety goggles when working with liquid refrigerant ( all of the above)

Front 5

Refrigerant-11 at 14.7 PSIA will boil at about:

Back 5

74.5°F

Front 6

When there is excessive moisture collecting in the purge unit of a low pressure refrigeration system, this indicates that the _________.

Back 6

Condenser or chiller barrel tubes are leaking.

Front 7

ASHRAE standard 15-1994 requires equipment room refrigerant sensors for what safety group classification?

Back 7

All refrigerant safety groups ( A1 B2 A2)

Front 8

When recharging a refrigeration system with R-11, what vapor pressure is necessary in the shells before charging with liquid?

Back 8

16.9" Hg vacuum

Front 9

After reaching the required recovery vacuum on a chiller, you should:

Back 9

Wait for at least a few minutes to see if the system pressure rises, indicating that there is still refrigerant in liquid form or in the oil.

Front 10

A hydrostatic tube test kit is used to:

Back 10

Determine if a tube leaks

Front 11

When charging a chiller, refrigerant vapor is introduced into the system before charging with liquid. This is because :

Back 11

Liquid charged into a deep vacuum will cause the refrigerant to boil and may lower temperatures enough to freeze the water in the tubes.

Front 12

When evacuating a system, the use of too large a vacuum pump can cause:

Back 12

Trapped water to freeze.

Front 13

On a low-pressure chiller with an open type compressor, the ________ is very susceptible to leaks.

Back 13

Shaft seal

Front 14

What steps may be taken to prevent air accumulation into an idle low pressure refrigeration system?

Back 14

System pressure should be maintained slightly above atmospheric

Front 15

Commercial and industrial process Refrigeration systems must be repaired when the leak rate exceeds ______ percent of the charge per year.

Back 15

35

Front 16

When recovering vapor from a low pressure refrigeration system the:

Back 16

System water pumps, the recovery compressor, and the recovery condenser water should all be on.

Front 17

Where does refrigerant go after it leaves the purge unit of a low pressure centrifugal system?

Back 17

Evaporator

Front 18

The purge unit takes it suction from the :

Back 18

Top of the condenser

Front 19

Which of the following repairs would ALWAYS be considered "major" under EPA's regulations?

Back 19

Replacement of an evaporator coil

Front 20

Charging refrigerant liquid into a refrigeration system when it is under 29 inchesHg vacuum can cause the:

Back 20

System water to freeze.

Front 21

According to the EPA, there is approximately ________ refrigerant vapor left in an average 350 ton R-11 chiller at 0PSIG pressure once all the R-11 liquid has been removed?

Back 21

100 LBS

Front 22

An oil sample should be taken when _______

Back 22

There has been a compressor burnout

Front 23

Both CFC-11 and HCFC-123 chillers require purge units because :

Back 23

The system operates below atmospheric pressure

Front 24

Refrigerant recovery typically starts with _______ it is faster.

Back 24

Liquid recovery

Front 25

Under EPA's regulations __________ is used to pressurize a low-pressure chiller for the purpose of opening the system for a non-major repair?

Back 25

Warming the refrigerant

Front 26

The primary water source for a recovery unit condensing coil is ________

Back 26

Local municipal water supply.

Front 27

Which statement is NOT true of the recycling and recovery equipment manufactured after November 15, 1993?

Back 27

It must be able to handle more than one refrigerant

Front 28

A system does not have to be evacuated all the way to the required level when:

Back 28

Leaks in the appliance make evacuation to the prescribed level unattainable

Front 29

Which action listed below is the proper method to reduce refrigerant loss from a purge unit on a CFC-11 chiller?

Back 29

Leak test and repair the chiller

Front 30

Identify the pressure corresponding to 32F for R-123:

Back 30

20" Hg vacuum

Front 31

What precaution should be taken prior to recovering refrigerant from a chiller suspected of having tube leaks

Back 31

Drain the water sides of the evaporator and condenser

Front 32

Pressure relief valves must never be:

Back 32

Installed in series

Front 33

If you are going to be removing oil from a low-pressure system, you should heat the oil because :

Back 33

Less refrigerant will be contained in the oil at the higher temperature

Front 34

After recovering the liquid refrigerant you must:

Back 34

Recover the vapor refrigerant

Front 35

EPA regulations require that any appliances containing more than 50 pounds of refrigerant(except for commercial and industrial process refrigeration) must be repaired when the leak rate exceeds ______ of the charge per year.

Back 35

15%

Front 36

If you are using a recovery machine manufactured BEFORE November 15, 1993, you must evacuate any low-pressure appliance to _______ before making a major repair.

Back 36

25" Hg vacuum

Front 37

On low-pressure chillers, moisture typically enters the refrigerant system through:

Back 37

Air leaks from areas with gaskets or fittings

Front 38

Refrigerant-11 at a pressure of 17 inches Hg vacuum has a saturation temperature of:

Back 38

35°F

Front 39

The lowest access point on a low pressure centrifugal air-conditioning unit is the:

Back 39

Evaporator charging valve

Front 40

A rupture disc on a recovery vessel for low pressure refrigerants relieves at:

Back 40

15PSIG

Front 41

According to ASHRAE guideline 3-1996 if the pressure in a system rises from 1mm Hg to a level above __________ during a standing vacuum test, system should be checked for leaks.

Back 41

2.5mm Hg

Front 42

During chiller evacuation, water is circulated to:

Back 42

Prevent freezing of the water

Front 43

When charging an R-410A water chiller, you must first charge with vapor to a pressure of at least __________ before switching to liquid charging.

Back 43

120 PSIG

Front 44

If you leak test a low pressure chiller with nitrogen in excess of 10 PSIG you could cause the _______ to fail.

Back 44

Rupture disc

Front 45

ASHRAE Standard 15-1994 requires that each machinery room must activate an alarm and mechanical ventilation before refrigerant concentrations exceed :

Back 45

The TLV-TWA (threshold limit valve -time weighted average )

Front 46

Which repair WOULD NOT fail under the EPA definition for " MAJOR MAINTENANCE, SERVICE, OR REPAIR "?

Back 46

Replacing an oil filter

Front 47

Refrigerant is added to a centrifugal machine through the:

Back 47

Evaporator charging valve

Front 48

What is meant by the term " high efficiency purge unit"?

Back 48

Those purge units which discharge a low percentage of refrigerant with the air which they remove

Front 49

The PRIMARY purpose of a purge unit on a CFC -11 chiller is to:

Back 49

Remove noncondensables from the system

Front 50

If you are using a recovery machine manufactured AFTER November 15, 1993, you must evacuate any low-pressure appliance to _ _ _ _ _ before making a major repair.

Back 50

25mm of Hg absolute

Front 51

If you suspect a leak in the water box of a chiller, you should place the leak detector probe ________ and sniff for refrigerants.

Back 51

Through a drain valve

Front 52

To determine how much vapor to charge into an evacuated chiller, you should charge with vapor until ____________.

Back 52

The system pressure corresponds to a refrigerant saturation temperature of 36F

Front 53

ASHRAE Standard 15-1994 requires the use of room sensors and alarms to detect :

Back 53

Refrigerant leaks

Front 54

The discharge from a rupture disc should be piped_______ for venting?

Back 54

Outdoors

Front 55

A centrifugal chiller's rupture disk is connected to the chiller's

Back 55

Evaporator

Front 56

To remove ice from sight glasses or viewing glasses use:

Back 56

An alcohol spray

Front 57

The maximum test pressure for leak testing a low pressure centrifugal is:

Back 57

10 PSIG

Front 58

According to ASHRAE standard 34 what is the safety classification of R-123?

Back 58

B1

Front 59

Excessive running of a purge system on a low pressure chiller generally indicates that the:

Back 59

System is leaking

Front 60

The typical design burst pressure for a rupture disk on a low-pressure centrifugal air-conditioning system is set at______

Back 60

15 PSI

Front 61

During the evacuation of a system containing large amounts of moisture, you can prevent freezing of this moisture by increasing the pressure with _________ gas.

Back 61

Nitrogen