ANSWERS SURE A+
✔✔If you are using a recovery machine manufactured AFTER November 15, 1993, you
must evacuate any low-pressure appliance to ________ before making a major repair.
a) 0 psig
b) 15 inches of Hg vacuum
b) 25 inches of Hg vacuum
d) 25 mm of Hg absolute - ✔✔d) 25 mm of Hg absolute
✔✔A chiller's rupture disk is connected to the system's ___________.
1) low pressure side
2) high pressure side
3) never used - ✔✔1) low pressure side
✔✔When leak testing a low pressure centrifugal, what is the maximum test pressure?
1) 0.1 psig
2) 10 psig
3) 10 inches of Mercury
4) 14.7 psia
, 5) 50 psig - ✔✔2) 10 psig
✔✔What is the EPA's estimate for how much refrigerant vapor is left in an average 350
ton R-11 chiller at 0 psig pressure, once all the R-11 liquid has been removed?
1) 1.5 lbs
2) 3.0 lbs
3) 10 lbs
4) 20 lbs
5) 100 lbs
6) 1000 lbs - ✔✔5) 100 lbs
✔✔How would you SAFELY reduce refrigerant loss from a purge-unit on a low pressure
unit?
1) Leak test and repair the chiller.
2) Seal the purge-unit discharge.
3) Plumb the purge-unit discharge back into the low side.
4) Plumb the purge-unit into the recovery unit. - ✔✔1) Leak test and repair the chiller.
✔✔When recharging a refrigeration system with R-11, why is refrigerant vapor added
first to raise the system pressure?
1) To prevent freezing of the water in the heat exchanger (water box).
2) To reduce the stress on the rupture disk.
3) To speed recharging.
4) To prevent condensation. - ✔✔1) To prevent freezing of the water in the heat
exchanger (water box).
✔✔If you suspected a low pressure system leak at the water box, where would you
place your leak detector?
1) At the rupture disk.
2) At the recovery port.
3) At the vent valve.
4) At the service port.
5) At the water box drain port. - ✔✔5) At the water box drain port.
✔✔A hydrostatic tube test kit will ________.
1) determine if a tube leaks
2) determine if there is water in the system
3) remove water from a machine
4) vent water - ✔✔1) determine if a tube leaks