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HVAC EPA 608 CERTIFICATION EXAM|| EPA 608
HVAC CERTIFICATION TEST WITH ALL
QUESTIONS AND 100% CORRECT ANSWERS
ALREADY GRADED A+|| LATEST AND COMPLETE
UPDATE 2024-2025 WITH EXPERT VERIFIED
SOLUTIONS|| ASSURED PASS!!!
Are there drop-in replacements for R-12 systems? Why or why not? ✔ No because
the new refrigerants are incompatible with the oils and lubricants used in R-12
systems.
What type of oil is used in R-134a and what oils will it mix with? ✔ Ester based
oils and they do not mix with other oils
What type of lubricant is used with HCFCs? ✔ Alkylbenzene lubricant
What is difference b/w ternary blend a azeotropic blend? ✔ Ternary blends are
three-part mixtures whereas azeotropic blends are blends of two or more
compounds that act like a single compound.
What is the trait of a hygroscopic lubricant? ✔ It absorbs (takes on) moisture
What is temperature glide and what type of blend won't have it? ✔ Temp. blend is
the difference between the dew point and the bubble point
Under what circumstances can recovered refrigerant be used? ✔ It may be returned
to the appliance from which it was removed or to another appliance owned by the
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same person without being recycled or reclaimed, unless the appliance is an
MVAC or MVAC-like appliance
Where should you remove the refrigerant in a system that has a condenser below
the receiver? ✔ Condenser outlet
How must you recover refrigerant from a parallel system? Why? ✔ Isolate a
parallel compressor system in order to recover refrigerant. Failure to isolate a
parallel compressor system will cause an open equalization that will prevent
refrigerant recovery
Where do leaks commonly occur in low pressure systems? What about open-drive
type compressor systems? ✔ Leaks in gaskets or fittings. The SHAFT SEAL in
open-drive compressor low pressure refrigeration systems is particularly
susceptible to leaks
Does refrigerant go out of the system in low pressure or does air and moisture go
in? Why? ✔ A low-pressure system operates in a vacuum (below atmospheric
pressure) to enter the refrigeration system.
When should a low pressure system be leaked checked according to ASHRAE
guideline 3-1996? ✔ If the pressure in system rises from 1 mm Hg to a level above
2.5 mm Hg during vacuum testing
What does a purge unit do and what is a high efficiency purge unit? ✔ The purge
unit prevents the accumulation of non-condensable substances (air and moisture) in
order to keep the system clean and maintain efficiency: The purge unit removes air
and moisture to prevent reduced condenser surface area, increased head pressure,
compressor surge, increased pressure differential, and system corrosion. A high
efficiency purge system will expel very little refrigerant along with the air.
HVAC EPA 608 CERTIFICATION EXAM|| EPA 608
HVAC CERTIFICATION TEST WITH ALL
QUESTIONS AND 100% CORRECT ANSWERS
ALREADY GRADED A+|| LATEST AND COMPLETE
UPDATE 2024-2025 WITH EXPERT VERIFIED
SOLUTIONS|| ASSURED PASS!!!
Are there drop-in replacements for R-12 systems? Why or why not? ✔ No because
the new refrigerants are incompatible with the oils and lubricants used in R-12
systems.
What type of oil is used in R-134a and what oils will it mix with? ✔ Ester based
oils and they do not mix with other oils
What type of lubricant is used with HCFCs? ✔ Alkylbenzene lubricant
What is difference b/w ternary blend a azeotropic blend? ✔ Ternary blends are
three-part mixtures whereas azeotropic blends are blends of two or more
compounds that act like a single compound.
What is the trait of a hygroscopic lubricant? ✔ It absorbs (takes on) moisture
What is temperature glide and what type of blend won't have it? ✔ Temp. blend is
the difference between the dew point and the bubble point
Under what circumstances can recovered refrigerant be used? ✔ It may be returned
to the appliance from which it was removed or to another appliance owned by the
, 2|Pag e
same person without being recycled or reclaimed, unless the appliance is an
MVAC or MVAC-like appliance
Where should you remove the refrigerant in a system that has a condenser below
the receiver? ✔ Condenser outlet
How must you recover refrigerant from a parallel system? Why? ✔ Isolate a
parallel compressor system in order to recover refrigerant. Failure to isolate a
parallel compressor system will cause an open equalization that will prevent
refrigerant recovery
Where do leaks commonly occur in low pressure systems? What about open-drive
type compressor systems? ✔ Leaks in gaskets or fittings. The SHAFT SEAL in
open-drive compressor low pressure refrigeration systems is particularly
susceptible to leaks
Does refrigerant go out of the system in low pressure or does air and moisture go
in? Why? ✔ A low-pressure system operates in a vacuum (below atmospheric
pressure) to enter the refrigeration system.
When should a low pressure system be leaked checked according to ASHRAE
guideline 3-1996? ✔ If the pressure in system rises from 1 mm Hg to a level above
2.5 mm Hg during vacuum testing
What does a purge unit do and what is a high efficiency purge unit? ✔ The purge
unit prevents the accumulation of non-condensable substances (air and moisture) in
order to keep the system clean and maintain efficiency: The purge unit removes air
and moisture to prevent reduced condenser surface area, increased head pressure,
compressor surge, increased pressure differential, and system corrosion. A high
efficiency purge system will expel very little refrigerant along with the air.
