ACCURATE ANSWERS
After installation, the refrigerant piping for an A2L system must be:
cleaned with an alcohol-based solution to remove grease and oil.
pressurized with dry nitrogen to perform a leak test.
pressurized with a non-flammable refrigerant (A1) to perform a leak test.
vibration tested using whichever method is approved by the local code authority.
correct answer pressurized with dry nitrogen to perform a leak test.
After reaching the required recovery level on a system that is charged with an A2L
refrigerant:
a nitrogen sweep should be done to remove any residual refrigerant vapor.
an alcohol-based solution must be used to remove any oil or grease.
the refractive index of the compressor must be tested.
the system must stand idle for 60 minutes prior to beginning any work on it.
correct answer a nitrogen sweep should be done to remove any residual
refrigerant vapor.
,An uppercase letter designation (R-407A, R-407B, R-407C) is used when
refrigerant blends are:
Composed of the same refrigerant, but with the same percentages of each.
Composed of different refrigerants but have the same thermodynamic properties.
Composed of the same refrigerants but manufactured by different companies.
Composed of the same refrigerants, but with different percentages of each.
correct answer Composed of the same refrigerants, but with different
percentages of each.
Atmospheric pressure (0 PSIG) is equal to approximately:
25 inches of mercury.
500 microns.
760,000 inches of mercury.
760,000 microns. correct answer 760,000
Before beginning the installation of a system that is charged with an A2L
refrigerant:
, a local code official must approve the site of the installation.
NFPA 704 hazard placards must be placed in visible locations around the
perimeter of the jobsite.
permanent mechanical ventilation must be installed in the structure.
verify that all the components being installed are designed for use with A2L
refrigerants. correct answer verify that all the components being installed are
designed for use with A2L refrigerants.
DOT regulations require refrigerant cylinders over 2.2 pounds of a 2L refrigerant
to be equipped with:
A dip tube.
A fire suppression mechanism.
Pressure relief valve.
Locking valve caps. correct answer Pressure relief valve.
EPA Section 608 regulations require that if a system is charged with a flammable
refrigerant, the equipment must have: