EPA 608 Type 3 Exam Questions &
Answers Updated Solution
1. On low pressure chillers, moisture typically enters the refrigerant system through - ANS ✔✔ -
air leaks from areas with gaskets or fittings
2. The maximum test pressure for leak testing a low pressure centrifugal is: - ANS ✔✔ - 10 psig
3. A hydrostatic tube test kit is used to: - ANS ✔✔ - determine if a tube leaks
4. Commercial and industrial process refrigeration systems must be repaired when the leak rate
exceeds ____ of the charge per year. - ANS ✔✔ - 35%
5. A rupture disc on a recovery vessel for a low pressure refrigerants relieves at: - ANS ✔✔ - 15
psig
6. According to ASHRAE Guideline 3-1996, if the pressure in a system rises from 1 mm Hg to a
level above ____ during a standing vacuum test, the system should be checked for leaks. - ANS
✔✔ - 2.5 mm Hg
7. The primary water source for a recovery unit condensing coil is _____. - ANS ✔✔ - local
municipal water supply
8. When recharging a refrigeration system with R-11, what vapor pressure is necessary in the
shells before changing with liquid? - ANS ✔✔ - 16.9" Hg vacuum
9. After recovering the liquid refrigerant you must: - ANS ✔✔ - recover the vapor refrigerant
, 10. According to the EPA there is approximately _____ refrigerant vapor left in an average 350 ton
R-11 chiller at 0 psig pressure once all the R-11 liquid has been removed. - ANS ✔✔ - 100
pounds
11. Charging refrigerant liquid into a refrigeration system when it is under a 29 inch Hg vacuum can
cause the: - ANS ✔✔ - system water to freeze
12. A system does not have to be evacuated all the way to the required level when: - ANS ✔✔ -
leaks in the appliance make evacuation to the prescribed level unattainable
13. Which of the following repairs would ALWAYS be considered "major" under EPA's - ANS ✔✔ -
replacement of evaporator coil
14. Under EPA's regulation's _______ is used to pressurize a low pressure chiller for the purpose of
opening the system for a non-major repair? - ANS ✔✔ - warming the refrigerant
15. If you are using a recovery machine manufactured AFTER 11-15-93 you must evacuate a low
pressure appliance to _______ before making a major repair. - ANS ✔✔ - 25 mm of Hg absolute
16. After reaching the required recovery vacuum on a chiller, you should - ANS ✔✔ - Wait for at
least a few minutes to see if the system pressure rises, indicating that there is still refrigerant in
a liquid form or in the oil
17. The pressure corresponding to 32 F for R-123 - ANS ✔✔ - 20 inches of HG vacuum
18. When evacuating a system the use of too large a vacuum pump can cause? - ANS ✔✔ - trapped
water to freeze
19. Refrigerant-11 at a pressure of 17 inches HG vacuum has a saturation temperature of: - ANS
✔✔ - 35F
Answers Updated Solution
1. On low pressure chillers, moisture typically enters the refrigerant system through - ANS ✔✔ -
air leaks from areas with gaskets or fittings
2. The maximum test pressure for leak testing a low pressure centrifugal is: - ANS ✔✔ - 10 psig
3. A hydrostatic tube test kit is used to: - ANS ✔✔ - determine if a tube leaks
4. Commercial and industrial process refrigeration systems must be repaired when the leak rate
exceeds ____ of the charge per year. - ANS ✔✔ - 35%
5. A rupture disc on a recovery vessel for a low pressure refrigerants relieves at: - ANS ✔✔ - 15
psig
6. According to ASHRAE Guideline 3-1996, if the pressure in a system rises from 1 mm Hg to a
level above ____ during a standing vacuum test, the system should be checked for leaks. - ANS
✔✔ - 2.5 mm Hg
7. The primary water source for a recovery unit condensing coil is _____. - ANS ✔✔ - local
municipal water supply
8. When recharging a refrigeration system with R-11, what vapor pressure is necessary in the
shells before changing with liquid? - ANS ✔✔ - 16.9" Hg vacuum
9. After recovering the liquid refrigerant you must: - ANS ✔✔ - recover the vapor refrigerant
, 10. According to the EPA there is approximately _____ refrigerant vapor left in an average 350 ton
R-11 chiller at 0 psig pressure once all the R-11 liquid has been removed. - ANS ✔✔ - 100
pounds
11. Charging refrigerant liquid into a refrigeration system when it is under a 29 inch Hg vacuum can
cause the: - ANS ✔✔ - system water to freeze
12. A system does not have to be evacuated all the way to the required level when: - ANS ✔✔ -
leaks in the appliance make evacuation to the prescribed level unattainable
13. Which of the following repairs would ALWAYS be considered "major" under EPA's - ANS ✔✔ -
replacement of evaporator coil
14. Under EPA's regulation's _______ is used to pressurize a low pressure chiller for the purpose of
opening the system for a non-major repair? - ANS ✔✔ - warming the refrigerant
15. If you are using a recovery machine manufactured AFTER 11-15-93 you must evacuate a low
pressure appliance to _______ before making a major repair. - ANS ✔✔ - 25 mm of Hg absolute
16. After reaching the required recovery vacuum on a chiller, you should - ANS ✔✔ - Wait for at
least a few minutes to see if the system pressure rises, indicating that there is still refrigerant in
a liquid form or in the oil
17. The pressure corresponding to 32 F for R-123 - ANS ✔✔ - 20 inches of HG vacuum
18. When evacuating a system the use of too large a vacuum pump can cause? - ANS ✔✔ - trapped
water to freeze
19. Refrigerant-11 at a pressure of 17 inches HG vacuum has a saturation temperature of: - ANS
✔✔ - 35F
