EPA 608 609 Type III 2 — Questions and Answers
Question 1: Type III certification covers the servicing of which type of appliance?
- Low-pressure appliances (Correct answer)
- High-pressure appliances
- Small appliances
- Motor vehicle air conditioners
Correct answer: Low-pressure appliances
Type III certification is required to service or dispose of low-pressure appliances.
Question 2: Which refrigerant is commonly found in low-pressure appliances?
- R-123 (Correct answer)
- R-410A
- R-134a
- R-22
Correct answer: R-123
R-123 (and previously R-11) is a typical low-pressure refrigerant used in centrifugal chillers.
Question 3: Low-pressure refrigerants have a boiling point at atmospheric pressure that is generally:
- Above 50°F (10°C) (Correct answer)
- Below 0°F (-18°C)
- Exactly 32°F (0°C)
- Below -40°F (-40°C)
Correct answer: Above 50°F (10°C)
Low-pressure refrigerants boil at relatively high temperatures, above 50°F at atmospheric pressure.
Question 4: A low-pressure appliance normally operates with the low side:
- Under a vacuum (below atmospheric pressure) (Correct answer)
- Above 200 psig
- At exactly atmospheric pressure
- Above 500 psig
Correct answer: Under a vacuum (below atmospheric pressure)
Low-pressure systems often operate under a partial vacuum on the low side.
Question 5: Because low-pressure systems run under a vacuum, the main concern with leaks is:
- Air and moisture leaking into the system (Correct answer)
- Refrigerant rapidly venting out
- Oil being forced out
- High-pressure rupture
Correct answer: Air and moisture leaking into the system
A vacuum allows non-condensables and moisture to be drawn into the appliance.
Question 6: What device removes air and other non-condensables from a low-pressure chiller during operation?
- Purge unit (Correct answer)
- Receiver
- Filter-drier
- Accumulator
Correct answer: Purge unit
A purge unit removes air and non-condensables that accumulate in low-pressure systems.
Question 7: The required recovery level for a low-pressure appliance with a full charge during disposal is:
- 25 mm Hg absolute (Correct answer)
- 0 psig
- 10 inches of vacuum
- 15 psig
Correct answer: 25 mm Hg absolute
Disposal of low-pressure appliances requires evacuation to 25 mm Hg absolute.
EPA 608 609 Type III 2
Type III certification covers the servicing of which type of appliance?