Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

EPA Sec608 > Type 3 prep > Flashcards

Type 3 prep Flashcards

1
Q

What must a technician be certified in to maintain, service, repair, or dispose of low-pressure appliances?

A

Type 3 or Universal EPA certification.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are most low-pressure appliances subject to?

A

A lower allowable leak rate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why will leaks in gaskets or fittings cause air and moisture to enter the sytem?

A

Low pressure systems operate in a vacuum.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What do low pressure chillers that operate in a vacuum require?

A

Purge units.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is the purpose of a purge unit?

A

To remove non-condensables that leak into the system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What generally indicates a leaking system?

A

Excessive running of a purge system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What two things does high head pressure in a low-pressure system indicate?

A

Air in the system and the purge unit may not be operating properly.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What type of purge units discharge a low percentage of refrigerant with the air they remove?

A

High-efficiency purge units.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is used to determine if a tube is leaky ?

A

Hydrostatic tube test kit.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What can cause the rupture disc to fail when pressure testing a low-pressure refrigeration system with nitrogen?

A

Pressures greater than 10 psig.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where could the leak be in a low-pressure refrigeration system if excessive moisture continuously collects in the purge unit?

A

In the condenser or the chiller barrel tubes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How do you prevent air from accumulating into an idled low-pressure system?

A

Maintain system pressure slightly above atmospheric pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How do you check for a refrigerant leak to the water side of a chiller?

A

Place a leak detector probe in the drain valve opening of the water box with the water removed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What must you do prior to recovering refrigerant from a chiller suspected of having tube leaks?

A

Drain the water sides of the evaporator and condenser.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What should be done if the pressure in a system rises from 1mm Hg to 2.5mm Hg during a standard vacuum test?

A

The system should be checked for leaks.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What 3 things can the owner do when an appliance using regulated refrigerant exceeds the threshold leak rate?

A

Repair appliance to below the leak rate threshold, retrofit, or retire the appliance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What EPA leak repair category do chillers generally belong to?

A

Comfort cooling.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What category would a chiller that diverts 55% of its cooling to manufacturing and 45% to cooling its office space be in?

A

Industrial process refrigeration leak rate category.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How can you find a chiller’s normal charge for leak rate calcualtions?

A

The charge is stated on the equipment nameplate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

When must the leak rate of an appliance using regulated refrigerant be calculated?

A

When topping off or recharging a system due to a loss of charge.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How much time does an owner or operator have to retrofit or retire an appliance with 50 or more pounds of refrigerant that has exceeded the threshold leak rate?

A

18 months.

22
Q

What can not be used as an excuse to extend the appliance leak repair deadline?

A

Failure to have a certified service technician available.

23
Q

What does not require removing the appliance and storing it in a warehouse at the facility?

A

System mothballing.

24
Q

How much time does an owner or operator have to repair an appliance with 50 or more pounds of refrigerant so that it leaks below the threshold?

A

30 days.

25
Q

When must a follow up verification test be conducted within 10 days?

A

When a chiller with a charge of 200 pounds or more of ozone-depleting refrigerant has passed the initial verification leak test.

26
Q

What records is the owner or operator responsible for keeping?

A

All leak inspections, initial verification, and any completed leak repair follow-up verification tests for 3 years.

27
Q

What is the high-pressure cut out on a recovery unit used for low-pressure chillers?

A

Typically 10 psig.

28
Q

Why must you first remove the liquid refrigerant before the vapor refrigerant in a large low-pressure system?

A

Because of the high volume of liquid refrigerant.

29
Q

How much vapor refrigerant will an average 350-ton, R-123 chiller, at 0 psig have after all the liquid refrigerant has been removed?

A

Approximately 100 pounds.

30
Q

Why may it be necessary to break the vacuum using nitrogen during an evacuation of a system containing large amounts of moisture?

A

Increasing the pressure with nitrogen prevents the moisture from freezing and increases the speed of dehydration.

31
Q

What allows for faster recovery of large quantities of refrigerant?

A

A water-cooled recovery unit.

32
Q

What should be on during vapor or liquid removal from a low-pressure refrigeration system?

A

System’s water pumps, recovery compressor, and recovery condenser water.

33
Q

What will also help achieve a faster refrigerant recovery?

A

Raising the temperature of the system or the room the chiller is located.

34
Q

Why should refrigerant oil be heated to 130F when being removed?

A

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

35
Q

What relieves at 15 psig for low-pressure refrigerants?

A

The rupture disc on a recovery vessel.

36
Q

What must recovery and recycling equipment be labeled as?

A

Certified to meet EPA’s requirements.

37
Q

What kind of repairs allow you to warm the system’s liquid refrigerant with hot water or warming blankets to bring it out of a vacuum?

A

When performing non-major repairs.

38
Q

What must be done before disposing of a low-pressure appliance?

A

The refrigerant must be recovered or evacuated to 25mm of Hg absolute.

39
Q

When must an oil sample be taken if the unit has had a compressor burn-out?

A

Before recovery/evacuation or dehydration.

40
Q

What should you do when evacuating/dehydrating a system that contains a large amount of moisture to break the vacuum?

A

Triple evacuate/dehydrate using dry-nitrogen.

41
Q

How is refrigerant vapor re-introduced into the chiller to prevent freezing the water in the heat exchanger tube bundle?

A

It is charged to a pressure which corresponds to its saturation temperature above freezing.

42
Q

What is the lowest access point on a low-pressure appliance?

A

The evaporator charging valve.

43
Q

How is absolute pressure (psia) converted to guage pressure (psig)?

A

Subract 14.7 from the absolute pressure (psia). ie 14.7 psia equals 0 psig.

44
Q

When does ASHRAE Standard 15-2013 require that each machinery room activate an alarm and a mechanical ventilation system?

A

When the TLV-TWA (Threshold Limit Value - Time Weighted Average) is exceeded.

45
Q

Why is the use of room sensors and alarms to detect refrigerant leaks of all refrigerant types required?

A

Not only because of refrigerant flammability and toxicity levels but because refrigerants are heavier than air and can displace oxygen.

46
Q

What should be worn when working with liquid refrigerant for low-pressure systems?

A

Gloves and safety goggles.

47
Q

What should be piped outdoors to prevent venting into the machine room?

A

The discharge from a rupture disc or pressure relief valves.

48
Q

How should all pressure relief valves be piped or installed?

A

In parallel, never in series.

49
Q

What is located on the evaporator of centrifugal chiller?

A

A 15 psig rated rupture disc.

50
Q

What do you use to remove ice from sight glasses?

A

Isopropyl alcohol.

EPA Sec608 (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions