ANSWERS RATED A+
✔✔Under EPA regulations, chillers used in commercial refrigeration and/or industrial
process cooling, with a leak rate of _____% must be repaired. - ✔✔35%
✔✔An estimated 15% of all emissions from low-pressure chillers occur during: -
✔✔Purging
✔✔All the liquid has been recovered. What is the next step in the recovery process? -
✔✔Recover the remaining vapor refrigerant
✔✔An average low-pressure chiller requires about 3 pounds of refrigerant per ton. The
large amount of liquid refrigerant involved is removed more quickly: - ✔✔By a special
liquid pump from the evaporator into the recovery vessel
✔✔When evacuating the refrigerant from a low-pressure chiller, the recovery unit's high-
pressure cutout is set for_____ psig? - ✔✔10
✔✔Almost all of the refrigerants in general use are rated under ASHRAE 34 standard
as Group A-l which means non-toxic and non-flammable. But _______ is listed s Group
BI, which means that it is non-flammable but is somewhat toxic. - ✔✔R-123
✔✔Water must be circulated through a chiller during refrigerant evacuation in order to: -
✔✔Prevent freezing of the water
✔✔For what refrigerant is an equipment room refrigerant sensor required under
ASHRAE standard 15? - ✔✔R123
✔✔Which of the following repairs would ALWAYS be considered "major" under EPA's
regulations? - ✔✔Replacement of an evaporator coil
✔✔The most common refrigerant used by low-pressure chillers has been a CFC (R-11).
The current replacement refrigerant for R- 11 is a HCFC, which is: - ✔✔R-123
✔✔The EPA defines _____________ as maintenance, service or repair that involves
removal of the compressor, condenser, evaporator or auxiliary heat exchanger as: -
✔✔Major maintenance
✔✔ASHRAE Standard 15 requires that a specific refrigerant sensor be provided for
refrigerants under Code B-1. Currently this applies to only: - ✔✔R-123
, ✔✔The PRIMARY purpose of a purge unit is to: - ✔✔Remove non-condensable from
the system
✔✔The RPM of a single stage centrifugal compressor is approximately: - ✔✔30,000
✔✔What will the evaporator temperature of R- 11 be at a vapor pressure of 13.1 psig? -
✔✔ll0 degrees F
✔✔The rupture disk of a low pressure chiller is connected to the: - ✔✔Low side
✔✔With TYPE III certification only, you can also work on Type I and Type II systems. -
✔✔False
✔✔On low-pressure chillers, moisture MOST FREQUENTLY enters the refrigerant
system through: - ✔✔Air leaks from gaskets or fittings
✔✔A Type III service technician's vacuum pump should be capable of pulling a vacuum
of at least: - ✔✔500 microns
✔✔Before a low pressure appliance is dismantled and salvaged: - ✔✔The refrigerant
must be recovered
✔✔After reaching the required recovery vacuum on an appliance, you should: - ✔✔Wait
for at least a few minutes to see if the system pressure rises, indicating that there is still
refrigerant in liquid form or in the oil
✔✔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? - ✔✔100 lbs.
✔✔The "end bell" at the end of the chiller barrel and the condenser of the centrifugal
chiller where the water enters and leaves that heat exchanger is called a - ✔✔Water
box
✔✔Under EPA's regulations, which of the following methods can be used to pressurize
a system for the purpose of opening the system for a non-major repair? - ✔✔Controlled
hot water
✔✔Recovery cylinders are color-coded: - ✔✔Gray with Yellow tops
✔✔Increasing the temperature of the system oil to 130 degrees F during recovery: -
✔✔Maximizes the recovery of refrigerant from the oil