EPA SECTION 608 TECHNICIAN CERTIFICATION STUDY GUIDE |
QUESTIONS AND ANSWERS | VERIFIED AND WELL DETAILED
ANSWERS | LATEST EXAM
What are the typical uses of the center port of gauge set? - CORRECT
ANSWER - Used during evacuation, charging and recovery procedures.
What color are the gauges on a manifold gauge set? - CORRECT ANSWER -
Low pressure is blue, High pressure is red.
What are the typical ranges of pressure measurements used on the gauges of a
manifold gauge set? - CORRECT ANSWER - High side is 0 to 500 PSIG;
Low side is 0 to 350 PSIG and 0 to 30 in. Hg below atmospheric pressure.
Is the refrigerant leaving a condenser at a high or low pressure? Is it a liquid or
a gas? - CORRECT ANSWER - High pressure, liquid.
Is the refrigerant entering the expansion valve (variable metering device) a
liquid or gas? - CORRECT ANSWER - Liquid, high pressure.
Is the pressure of the refrigerant entering the compressor high or low? -
CORRECT ANSWER - Low pressure vapor.
Where in a refrigerant circuit does a liquid boil to absorb heat? - CORRECT
ANSWER - In the evaporator.
The refrigerant in the suction line is a gas that has been heated above its
saturation. What is this condition called? - CORRECT ANSWER -
Superheated vapor.
,What can cause liquid refrigerant to migrate to a compressor crankcase? -
CORRECT ANSWER - If the compressor is located in the coldest location in
the circuit.
List two conditions that can quickly damage a compressor that is starting to
run? - CORRECT ANSWER - Operating while in a deep vacuum or when the
service valves are closed.
What system failures require taking an oil sample? - CORRECT ANSWER - A
compressor burnout or if the unit has had a leak.
Is flushing with refrigerant an acceptable tube cleaning method? - CORRECT
ANSWER - No.
In addition to preventing and repairing leaks what else should a technician do to
conserve refrigerant? - CORRECT ANSWER - Recover and recycle used
refrigerants.
What factors affect the speed of an evacuation? - CORRECT ANSWER -
Pump size, hose length, hose diameter, size of system to be evacuated, ambient
temperature, suction line size, and the amount of moisture in the system.
How should gauge set hoses be sized for use in evacuating a system? -
CORRECT ANSWER - Use the shortest length and the largest diameter
possible for the quickest evacuation. At least as large as the vacuum pump inlet.
When evacuating what is the benefit of using short hoses with large diameters? -
CORRECT ANSWER - Reduces emissions, pressure drop and evacuation
time.
,Which connection determines the preferred size of hoses used with a vacuum
pump? - CORRECT ANSWER - The vacuum pump inlet.
As the capacity and suction hose size increase what happens to the time needed
for an evacuation? - CORRECT ANSWER - Time is reduced.
What purpose is served by heating a system during dehydration? - CORRECT
ANSWER - To speed up moisture removal.
Does a thorough evacuation remove moisture from a system? - CORRECT
ANSWER - Yes.
What can happen to oil in the compressor if the moisture is left in an operating
system? - CORRECT ANSWER - The oil will form hydrofluoric and
hydrochloric acids which will corrode the internal parts of the system.
What is the result of over-evacuating a system? - CORRECT ANSWER - No
damage will be done.
How can a system be leak checked using a low pressure gauge? - CORRECT
ANSWER - Vacuum reading will rise when vacuum pump is turned off.
How close should the vacuum gauge be connected to the vacuum pump during
evacuation? - CORRECT ANSWER - As far away as possible.
When measuring the vacuum of a system being evacuated the system must be
isolated. What must be done to the vacuum pump? - CORRECT ANSWER -
Turn it off and valve it off.
, What is ozone? - CORRECT ANSWER - 3 atoms of oxygen. It blocks much
of the harmful ultraviolet radiation (uv-b) emitted from the sun and it keeps our
earth's temperature stable.
How much ozone can a chlorine atom destroy in the stratosphere? - CORRECT
ANSWER - One atom can destroy 100,000 ozone molecules.
What is Ozone Depletion Potential (ODP)? - CORRECT ANSWER - The
ability of any chemical to deplete the ozone layer.
What is CFC? - CORRECT ANSWER - Chlorofluorocarbon.
Which refrigerants are CFC's? - CORRECT ANSWER - R-11,12,113,114.
Which chemical in the CFC refrigerants does the most damage to the ozone
layer? - CORRECT ANSWER - Chlorine.
What is an HCFC? - CORRECT ANSWER - Hydrochlorofluorocarbons.
Which refrigerants are HCFC's? - CORRECT ANSWER - R-22,123.
Which is more harmful to the ozone layer a CFC or an HCFC? - CORRECT
ANSWER - CFC's.
What is it about CFC's that make them more harmful to the stratosphere? -
CORRECT ANSWER - Chemical strength, they will not breakdown in the
lower atmosphere.
What is an HFC? - CORRECT ANSWER - A fluorocarbon that contains no
chlorine.
QUESTIONS AND ANSWERS | VERIFIED AND WELL DETAILED
ANSWERS | LATEST EXAM
What are the typical uses of the center port of gauge set? - CORRECT
ANSWER - Used during evacuation, charging and recovery procedures.
What color are the gauges on a manifold gauge set? - CORRECT ANSWER -
Low pressure is blue, High pressure is red.
What are the typical ranges of pressure measurements used on the gauges of a
manifold gauge set? - CORRECT ANSWER - High side is 0 to 500 PSIG;
Low side is 0 to 350 PSIG and 0 to 30 in. Hg below atmospheric pressure.
Is the refrigerant leaving a condenser at a high or low pressure? Is it a liquid or
a gas? - CORRECT ANSWER - High pressure, liquid.
Is the refrigerant entering the expansion valve (variable metering device) a
liquid or gas? - CORRECT ANSWER - Liquid, high pressure.
Is the pressure of the refrigerant entering the compressor high or low? -
CORRECT ANSWER - Low pressure vapor.
Where in a refrigerant circuit does a liquid boil to absorb heat? - CORRECT
ANSWER - In the evaporator.
The refrigerant in the suction line is a gas that has been heated above its
saturation. What is this condition called? - CORRECT ANSWER -
Superheated vapor.
,What can cause liquid refrigerant to migrate to a compressor crankcase? -
CORRECT ANSWER - If the compressor is located in the coldest location in
the circuit.
List two conditions that can quickly damage a compressor that is starting to
run? - CORRECT ANSWER - Operating while in a deep vacuum or when the
service valves are closed.
What system failures require taking an oil sample? - CORRECT ANSWER - A
compressor burnout or if the unit has had a leak.
Is flushing with refrigerant an acceptable tube cleaning method? - CORRECT
ANSWER - No.
In addition to preventing and repairing leaks what else should a technician do to
conserve refrigerant? - CORRECT ANSWER - Recover and recycle used
refrigerants.
What factors affect the speed of an evacuation? - CORRECT ANSWER -
Pump size, hose length, hose diameter, size of system to be evacuated, ambient
temperature, suction line size, and the amount of moisture in the system.
How should gauge set hoses be sized for use in evacuating a system? -
CORRECT ANSWER - Use the shortest length and the largest diameter
possible for the quickest evacuation. At least as large as the vacuum pump inlet.
When evacuating what is the benefit of using short hoses with large diameters? -
CORRECT ANSWER - Reduces emissions, pressure drop and evacuation
time.
,Which connection determines the preferred size of hoses used with a vacuum
pump? - CORRECT ANSWER - The vacuum pump inlet.
As the capacity and suction hose size increase what happens to the time needed
for an evacuation? - CORRECT ANSWER - Time is reduced.
What purpose is served by heating a system during dehydration? - CORRECT
ANSWER - To speed up moisture removal.
Does a thorough evacuation remove moisture from a system? - CORRECT
ANSWER - Yes.
What can happen to oil in the compressor if the moisture is left in an operating
system? - CORRECT ANSWER - The oil will form hydrofluoric and
hydrochloric acids which will corrode the internal parts of the system.
What is the result of over-evacuating a system? - CORRECT ANSWER - No
damage will be done.
How can a system be leak checked using a low pressure gauge? - CORRECT
ANSWER - Vacuum reading will rise when vacuum pump is turned off.
How close should the vacuum gauge be connected to the vacuum pump during
evacuation? - CORRECT ANSWER - As far away as possible.
When measuring the vacuum of a system being evacuated the system must be
isolated. What must be done to the vacuum pump? - CORRECT ANSWER -
Turn it off and valve it off.
, What is ozone? - CORRECT ANSWER - 3 atoms of oxygen. It blocks much
of the harmful ultraviolet radiation (uv-b) emitted from the sun and it keeps our
earth's temperature stable.
How much ozone can a chlorine atom destroy in the stratosphere? - CORRECT
ANSWER - One atom can destroy 100,000 ozone molecules.
What is Ozone Depletion Potential (ODP)? - CORRECT ANSWER - The
ability of any chemical to deplete the ozone layer.
What is CFC? - CORRECT ANSWER - Chlorofluorocarbon.
Which refrigerants are CFC's? - CORRECT ANSWER - R-11,12,113,114.
Which chemical in the CFC refrigerants does the most damage to the ozone
layer? - CORRECT ANSWER - Chlorine.
What is an HCFC? - CORRECT ANSWER - Hydrochlorofluorocarbons.
Which refrigerants are HCFC's? - CORRECT ANSWER - R-22,123.
Which is more harmful to the ozone layer a CFC or an HCFC? - CORRECT
ANSWER - CFC's.
What is it about CFC's that make them more harmful to the stratosphere? -
CORRECT ANSWER - Chemical strength, they will not breakdown in the
lower atmosphere.
What is an HFC? - CORRECT ANSWER - A fluorocarbon that contains no
chlorine.
