1. A technician is repairing a walk-in cooler that holds 80 pounds of R-22. What is the
maximum annual leak rate allowed before the EPA requires repairs?
A) 10%
B) 15%
C) 25%
D) 35%
For comfort cooling appliances with over 50 lbs of refrigerant, repairs are mandatory when
the annual leak rate exceeds 15%.
2. On a low-pressure chiller using R-11, you need to add refrigerant after a repair. Where
is the correct charging point?
A) The compressor discharge valve
B) The liquid line receiver outlet
C) The charging valve on the evaporator
D) The condenser inlet
Low-pressure chillers are charged into the evaporator charging valve to ensure proper
vapor entry and avoid slugging the compressor.
3. A technician recovers refrigerant from a system and stores it in a cylinder to be sent for
reclamation. What must be placed on that cylinder?
A) A hazardous waste symbol
B) A refrigerant label
C) A pressure test stamp
D) The owner’s name
Any cylinder returned for reclaiming must bear a refrigerant label identifying its contents
per EPA regulations.
,4. You are shipping several used refrigerant cylinders. How must they be positioned?
A) On their side with valves protected
B) Up-right with proper DOT classification tags
C) Stacked horizontally
D) Inverted to prevent leaks
DOT requires cylinders be shipped upright with proper classification tags for safety and
identification.
5. Which international treaty was the basis for Section 608 of the Clean Air Act?
A) Kyoto Protocol
B) The Montreal Protocol
C) Paris Agreement
D) Geneva Convention
*The Montreal Protocol (1989) established the phase-out of ozone-depleting substances,
forming the basis for Section 608.*
6. A technician is working with a blend refrigerant numbered in the 500 series. What is
true about this refrigerant?
A) It exhibits temperature glide
B) It acts like a single-component refrigerant (azeotrope)
C) It must always be charged as a vapor
D) It is non-azeotropic
Refrigerants numbered 500–599 are azeotropes, which behave as a single compound with
constant composition.
7. According to your notes, what date made it illegal to vent HFC refrigerants?
A) July 1, 1992
B) November 14, 1994
C) November 15, 1995
D) December 31, 1995
, HFC venting became illegal on November 15, 1995, as EPA determined all refrigerants
contribute to global warming.
8. A technician finds a low-pressure chiller with excessive moisture collecting in the purge
unit. What does this likely indicate?
A) Overcharged system
B) Tube leakage
C) Faulty compressor
D) High superheat
Excessive moisture in the purge unit typically indicates water tube leaks allowing moisture
ingress.
9. What is the maximum fill capacity by weight for a recovery cylinder?
A) 60%
B) 70%
C) 80%
D) 90%
Recovery cylinders must never be filled beyond 80% of their capacity by weight to prevent
hydrostatic rupture.
10. A technician is evacuating a system and wants the most accurate vacuum reading.
Where should the vacuum gauge be connected?
A) At the vacuum pump inlet
B) As far from the vacuum pump as possible
C) At the compressor discharge
D) On the liquid line
The vacuum gauge should be placed far from the pump to avoid false readings due to
pressure drop in hoses.
, 11. What is the definition of a Type I appliance under EPA 608?
A) Any appliance with over 50 lbs of refrigerant
B) *Factory-sealed with 5 lbs of refrigerant or less*
C) Low-pressure centrifugal chiller
D) Motor vehicle air conditioner
Type I appliances are small appliances manufactured, charged, and hermetically sealed
with ≤5 lbs of refrigerant.
12. A technician sees bubbles in the liquid line sight glass of an R-22 system. What does this
most likely indicate?
A) Overcharged system
B) Low refrigerant charge
C) Clogged filter drier
D) High subcooling
Bubbles in the sight glass indicate insufficient liquid refrigerant, meaning the charge is
low.
13. Which oil MUST be used with all HFC refrigerants in HVAC/R systems?
A) Mineral oil
B) Alkylbenzene
C) Polyolester (POE)
D) Naphthenic oil
POE oil is required for HFCs because mineral oil is not miscible with HFC refrigerants.
14. A technician is recovering refrigerant from a system using self-contained equipment.
What does this mean?
A) Using the system’s own compressor
B) Recovery without the appliance’s components
C) Recovery only in vapor phase
D) Using a passive system-dependent device
maximum annual leak rate allowed before the EPA requires repairs?
A) 10%
B) 15%
C) 25%
D) 35%
For comfort cooling appliances with over 50 lbs of refrigerant, repairs are mandatory when
the annual leak rate exceeds 15%.
2. On a low-pressure chiller using R-11, you need to add refrigerant after a repair. Where
is the correct charging point?
A) The compressor discharge valve
B) The liquid line receiver outlet
C) The charging valve on the evaporator
D) The condenser inlet
Low-pressure chillers are charged into the evaporator charging valve to ensure proper
vapor entry and avoid slugging the compressor.
3. A technician recovers refrigerant from a system and stores it in a cylinder to be sent for
reclamation. What must be placed on that cylinder?
A) A hazardous waste symbol
B) A refrigerant label
C) A pressure test stamp
D) The owner’s name
Any cylinder returned for reclaiming must bear a refrigerant label identifying its contents
per EPA regulations.
,4. You are shipping several used refrigerant cylinders. How must they be positioned?
A) On their side with valves protected
B) Up-right with proper DOT classification tags
C) Stacked horizontally
D) Inverted to prevent leaks
DOT requires cylinders be shipped upright with proper classification tags for safety and
identification.
5. Which international treaty was the basis for Section 608 of the Clean Air Act?
A) Kyoto Protocol
B) The Montreal Protocol
C) Paris Agreement
D) Geneva Convention
*The Montreal Protocol (1989) established the phase-out of ozone-depleting substances,
forming the basis for Section 608.*
6. A technician is working with a blend refrigerant numbered in the 500 series. What is
true about this refrigerant?
A) It exhibits temperature glide
B) It acts like a single-component refrigerant (azeotrope)
C) It must always be charged as a vapor
D) It is non-azeotropic
Refrigerants numbered 500–599 are azeotropes, which behave as a single compound with
constant composition.
7. According to your notes, what date made it illegal to vent HFC refrigerants?
A) July 1, 1992
B) November 14, 1994
C) November 15, 1995
D) December 31, 1995
, HFC venting became illegal on November 15, 1995, as EPA determined all refrigerants
contribute to global warming.
8. A technician finds a low-pressure chiller with excessive moisture collecting in the purge
unit. What does this likely indicate?
A) Overcharged system
B) Tube leakage
C) Faulty compressor
D) High superheat
Excessive moisture in the purge unit typically indicates water tube leaks allowing moisture
ingress.
9. What is the maximum fill capacity by weight for a recovery cylinder?
A) 60%
B) 70%
C) 80%
D) 90%
Recovery cylinders must never be filled beyond 80% of their capacity by weight to prevent
hydrostatic rupture.
10. A technician is evacuating a system and wants the most accurate vacuum reading.
Where should the vacuum gauge be connected?
A) At the vacuum pump inlet
B) As far from the vacuum pump as possible
C) At the compressor discharge
D) On the liquid line
The vacuum gauge should be placed far from the pump to avoid false readings due to
pressure drop in hoses.
, 11. What is the definition of a Type I appliance under EPA 608?
A) Any appliance with over 50 lbs of refrigerant
B) *Factory-sealed with 5 lbs of refrigerant or less*
C) Low-pressure centrifugal chiller
D) Motor vehicle air conditioner
Type I appliances are small appliances manufactured, charged, and hermetically sealed
with ≤5 lbs of refrigerant.
12. A technician sees bubbles in the liquid line sight glass of an R-22 system. What does this
most likely indicate?
A) Overcharged system
B) Low refrigerant charge
C) Clogged filter drier
D) High subcooling
Bubbles in the sight glass indicate insufficient liquid refrigerant, meaning the charge is
low.
13. Which oil MUST be used with all HFC refrigerants in HVAC/R systems?
A) Mineral oil
B) Alkylbenzene
C) Polyolester (POE)
D) Naphthenic oil
POE oil is required for HFCs because mineral oil is not miscible with HFC refrigerants.
14. A technician is recovering refrigerant from a system using self-contained equipment.
What does this mean?
A) Using the system’s own compressor
B) Recovery without the appliance’s components
C) Recovery only in vapor phase
D) Using a passive system-dependent device
