EPC TYPE 3 EXAM QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS)
|ALREADY GRADED A+
A hydrostatic thest kit will; - ANS -determine if a tube leaks.
When leak testing a low pressure centrifugal with nitrogen, what is the maximum
test pressure? - ANS -10 psig
Excessive running of a purge system on a low-pressure chiller generally indicates
what condition? - ANS -Leaking system.
According to ASRAE Guidline 3, the system should be checked for leaks if during a
standard vacuum test the pressure in a system rises from 1 mm toa level above; -
ANS -2.5 mm Hg.
If an owner operator of an apliance with 50 or more pounds of an ozone-
depleting refrigerant charge are required to retrofit or retire an appliance that has
exceeded the treshold leak rate, how many months do they have if the
replacement appliance uses a refrigerant exempt from venting prohibition? - ANS
-18 months
When must the leak rate of an appliance be calculated? - ANS -When topping off
or recharging a system due to a loss of charge.
Starting in 2019, what is the leak rate threshold for comfort cooling appliances
with a full charge of 50 Or more pounds. - ANS -10%
A typical setting for the high pressure cut-out control on a recvery unit used for
evacuating the refrigerant from a low-pressure chiler is; - ANS -10 psig
Refrigerant removal from a low-pressure system starts;with; - ANS -liquid removal
Why should the oil be removed from a low-pressure system at 130 degrees F.? -
ANS -Less refrigerant will be contained in the oil at the higher temperature.
, What is a typical advantage of a water cooled recovery unit? - ANS -Faster
recovery of large quantities of refrigerant.
Why must water be circulated through a chiller during refrigerant evacuation? -
ANS -To prevent freezing of water in the appliance.
Where is the lowest access point on a low-pressure air-conditioning appliance? -
ANS -Evaporator charging valve
What should you do after reaching the required recovery vacuum on a low-
pressure appliance? - ANS -Wait for at least a few minutes to see if the system
pressure rises before charging.
When should an appliance NOT be evacuated all the way to the prescribed level? -
ANS -When leaks in the appliance make evacuation to the prescribed level
unattainable.
Which of the following statements is true of recycling and recovery equipment? -
ANS -It must be labled as certified to meet EPA's requirements.
How long must a technician evacuating refrigerant from appliances with a full
charge of more than 5 pounds and less than 50 pounds that are being disposed of
keep records of the event? - ANS -3 years
What evacuation level must technicians recover refrigerant to before disposing a
low-pressure appliance? - ANS -25mm of Hg absolute
Which of the following always falls under the EPA definition for "major,
maintenance, service, or repair?" - ANS -Replacing a compressor.
Where is refrigerant added to a centrifugal machine? - ANS -Evaporator charging
valve.
Why do chillers using low-pressuree refrigerants require purge units? - ANS -
These systems operate below atmospheric pressure.
DETAILED ANSWERS (VERIFIED ANSWERS)
|ALREADY GRADED A+
A hydrostatic thest kit will; - ANS -determine if a tube leaks.
When leak testing a low pressure centrifugal with nitrogen, what is the maximum
test pressure? - ANS -10 psig
Excessive running of a purge system on a low-pressure chiller generally indicates
what condition? - ANS -Leaking system.
According to ASRAE Guidline 3, the system should be checked for leaks if during a
standard vacuum test the pressure in a system rises from 1 mm toa level above; -
ANS -2.5 mm Hg.
If an owner operator of an apliance with 50 or more pounds of an ozone-
depleting refrigerant charge are required to retrofit or retire an appliance that has
exceeded the treshold leak rate, how many months do they have if the
replacement appliance uses a refrigerant exempt from venting prohibition? - ANS
-18 months
When must the leak rate of an appliance be calculated? - ANS -When topping off
or recharging a system due to a loss of charge.
Starting in 2019, what is the leak rate threshold for comfort cooling appliances
with a full charge of 50 Or more pounds. - ANS -10%
A typical setting for the high pressure cut-out control on a recvery unit used for
evacuating the refrigerant from a low-pressure chiler is; - ANS -10 psig
Refrigerant removal from a low-pressure system starts;with; - ANS -liquid removal
Why should the oil be removed from a low-pressure system at 130 degrees F.? -
ANS -Less refrigerant will be contained in the oil at the higher temperature.
, What is a typical advantage of a water cooled recovery unit? - ANS -Faster
recovery of large quantities of refrigerant.
Why must water be circulated through a chiller during refrigerant evacuation? -
ANS -To prevent freezing of water in the appliance.
Where is the lowest access point on a low-pressure air-conditioning appliance? -
ANS -Evaporator charging valve
What should you do after reaching the required recovery vacuum on a low-
pressure appliance? - ANS -Wait for at least a few minutes to see if the system
pressure rises before charging.
When should an appliance NOT be evacuated all the way to the prescribed level? -
ANS -When leaks in the appliance make evacuation to the prescribed level
unattainable.
Which of the following statements is true of recycling and recovery equipment? -
ANS -It must be labled as certified to meet EPA's requirements.
How long must a technician evacuating refrigerant from appliances with a full
charge of more than 5 pounds and less than 50 pounds that are being disposed of
keep records of the event? - ANS -3 years
What evacuation level must technicians recover refrigerant to before disposing a
low-pressure appliance? - ANS -25mm of Hg absolute
Which of the following always falls under the EPA definition for "major,
maintenance, service, or repair?" - ANS -Replacing a compressor.
Where is refrigerant added to a centrifugal machine? - ANS -Evaporator charging
valve.
Why do chillers using low-pressuree refrigerants require purge units? - ANS -
These systems operate below atmospheric pressure.
