EPA Section 608 Technician Certification Study
Guide Perfectly Answered
What are the typical uses of the center port of gauge set? -Correct Ans-Used during
evacuation, charging and recovery procedures.
What color are the gauges on a manifold gauge set? -Correct Ans-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 Ans-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 Ans-High pressure, liquid.
Is the refrigerant entering the expansion valve (variable metering device) a liquid or gas?
-Correct Ans-Liquid, high pressure.
Is the pressure of the refrigerant entering the compressor high or low? -Correct Ans-Low
pressure vapor.
Where in a refrigerant circuit does a liquid boil to absorb heat? -Correct Ans-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 Ans-Superheated vapor.
,What can cause liquid refrigerant to migrate to a compressor crankcase? -Correct Ans-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 Ans-Operating while in a deep vacuum or when the service valves are closed.
What system failures require taking an oil sample? -Correct Ans-A compressor burnout
or if the unit has had a leak.
Is flushing with refrigerant an acceptable tube cleaning method? -Correct Ans-No.
In addition to preventing and repairing leaks what else should a technician do to
conserve refrigerant? -Correct Ans-Recover and recycle used refrigerants.
What factors affect the speed of an evacuation? -Correct Ans-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 Ans-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
Ans-Reduces emissions, pressure drop and evacuation time.
Which connection determines the preferred size of hoses used with a vacuum pump? -
Correct Ans-The vacuum pump inlet.
,As the capacity and suction hose size increase what happens to the time needed for an
evacuation? -Correct Ans-Time is reduced.
What purpose is served by heating a system during dehydration? -Correct Ans-To speed
up moisture removal.
Does a thorough evacuation remove moisture from a system? -Correct Ans-Yes.
What can happen to oil in the compressor if the moisture is left in an operating system?
-Correct Ans-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 Ans-No damage will be done.
How can a system be leak checked using a low pressure gauge? -Correct Ans-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 Ans-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 Ans-Turn it off and valve it off.
What is ozone? -Correct Ans-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 Ans-One
atom can destroy 100,000 ozone molecules.
, What is Ozone Depletion Potential (ODP)? -Correct Ans-The ability of any chemical to
deplete the ozone layer.
What is CFC? -Correct Ans-Chlorofluorocarbon.
Which refrigerants are CFC's? -Correct Ans-R-11,12,113,114.
Which chemical in the CFC refrigerants does the most damage to the ozone layer? -
Correct Ans-Chlorine.
What is an HCFC? -Correct Ans-Hydrochlorofluorocarbons.
Which refrigerants are HCFC's? -Correct Ans-R-22,123.
Which is more harmful to the ozone layer a CFC or an HCFC? -Correct Ans-CFC's.
What is it about CFC's that make them more harmful to the stratosphere? -Correct Ans-
Chemical strength, they will not breakdown in the lower atmosphere.
What is an HFC? -Correct Ans-A fluorocarbon that contains no chlorine.
Which refrigerants are HFC's? -Correct Ans-R-134a,404a,407c,410a.
What is the ODP of the HFC refrigerant? -Correct Ans-Zero.
Which refrigerants contain chlorine? -Correct Ans-CFC's and HCFC's.
Guide Perfectly Answered
What are the typical uses of the center port of gauge set? -Correct Ans-Used during
evacuation, charging and recovery procedures.
What color are the gauges on a manifold gauge set? -Correct Ans-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 Ans-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 Ans-High pressure, liquid.
Is the refrigerant entering the expansion valve (variable metering device) a liquid or gas?
-Correct Ans-Liquid, high pressure.
Is the pressure of the refrigerant entering the compressor high or low? -Correct Ans-Low
pressure vapor.
Where in a refrigerant circuit does a liquid boil to absorb heat? -Correct Ans-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 Ans-Superheated vapor.
,What can cause liquid refrigerant to migrate to a compressor crankcase? -Correct Ans-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 Ans-Operating while in a deep vacuum or when the service valves are closed.
What system failures require taking an oil sample? -Correct Ans-A compressor burnout
or if the unit has had a leak.
Is flushing with refrigerant an acceptable tube cleaning method? -Correct Ans-No.
In addition to preventing and repairing leaks what else should a technician do to
conserve refrigerant? -Correct Ans-Recover and recycle used refrigerants.
What factors affect the speed of an evacuation? -Correct Ans-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 Ans-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
Ans-Reduces emissions, pressure drop and evacuation time.
Which connection determines the preferred size of hoses used with a vacuum pump? -
Correct Ans-The vacuum pump inlet.
,As the capacity and suction hose size increase what happens to the time needed for an
evacuation? -Correct Ans-Time is reduced.
What purpose is served by heating a system during dehydration? -Correct Ans-To speed
up moisture removal.
Does a thorough evacuation remove moisture from a system? -Correct Ans-Yes.
What can happen to oil in the compressor if the moisture is left in an operating system?
-Correct Ans-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 Ans-No damage will be done.
How can a system be leak checked using a low pressure gauge? -Correct Ans-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 Ans-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 Ans-Turn it off and valve it off.
What is ozone? -Correct Ans-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 Ans-One
atom can destroy 100,000 ozone molecules.
, What is Ozone Depletion Potential (ODP)? -Correct Ans-The ability of any chemical to
deplete the ozone layer.
What is CFC? -Correct Ans-Chlorofluorocarbon.
Which refrigerants are CFC's? -Correct Ans-R-11,12,113,114.
Which chemical in the CFC refrigerants does the most damage to the ozone layer? -
Correct Ans-Chlorine.
What is an HCFC? -Correct Ans-Hydrochlorofluorocarbons.
Which refrigerants are HCFC's? -Correct Ans-R-22,123.
Which is more harmful to the ozone layer a CFC or an HCFC? -Correct Ans-CFC's.
What is it about CFC's that make them more harmful to the stratosphere? -Correct Ans-
Chemical strength, they will not breakdown in the lower atmosphere.
What is an HFC? -Correct Ans-A fluorocarbon that contains no chlorine.
Which refrigerants are HFC's? -Correct Ans-R-134a,404a,407c,410a.
What is the ODP of the HFC refrigerant? -Correct Ans-Zero.
Which refrigerants contain chlorine? -Correct Ans-CFC's and HCFC's.
