Chapter 9 Introduction to Refrigerating
HFC's have an ozone depletion potential of _________?
0
When the compressor is running, the temperature of the evaporator tuning is about ________ than the temperature of the refrigerant within.
10*F warmer
When the compressor is running on a system with a standard air-cooled condenser, the temperature different between ambient ate and condenser refrigerant is about ________.
30*F
Section ________ of the Clean Air Act requires that all technicians have certification in order to service HVACR equipment.
608
Lubricants made from propylene and benzene and designed for use with CFCs ,HCFCs, and blends that include CFCs and HCFCs describes _________ lubricants
AB
The most commonly used expendable refrigerants include the following except __________.
Ammonia (R-717)
Which refrigerant blend responds to temperature change like a single refrigerant?
Azeotropic
A halogenated refrigerant classification with high ODP and no longer manufactured since 1995 describes ___________
CFC's
Which type of refrigerant has the highest ozone depletion potential?
CFC's
A refrigerant's global warming potential (GWP) is based on the ratio of its warminng effect compared to the warming effect of ________?
Carbon Dioxide
Often, the number assigned to a specific refrigerant is associated with the refrigerants ___________.
Chemistry
When refrigeration lubricants is found to be dark black in color, pungent in odor, and containing metal shavings, it is likely that the ________ failed.
Compressor
R-508B color
Dark Blue
The US governmental body charged with enforcing the regulations of the Clean Air Act is the
Environmenal Protection Agency (EPA)
True or False? Refrigeration lubricants are stable fluids that should be kept in open containers or cylinders that are vented to atmosphere.
False
A refrigeration lubricant with a high _______ point may have excessive wax separation, which can clog the system.
Floc
The separating of a zeotropic blend's individual refrigerants during phase change is called _________.
Fractionation
Liquid refrigerant that are used to quickly freeze food products are called ___________.
Freezants
In a refrigerant blend contains an HCFC and an HFC, it is considered a(n) ____________.
HCFC
A refrigerant classification with a moderate ODP level but high GWP with a phaseout scheduled for 2030 describes __________.
HCFCs
A refrigerant classification of organic substances with 0 ODP, low GWP, low toxicity, but high flammability and used in standalone freezers and domestic refrigerant-freezers describes_________
HCs
A partially halogenated refrigerant classification with 0 ODP but high GWP describes _________
HFC's
A refrigerants classification with 0 ODP, low toxicity, slightly flammable, and used in some automotive air-conditioning systems describes __________
HFO's
A refrigerant that is classified as B3 has ________.
High toxicity and no flammability
Which of the following is not a characteristic of R-717?
It is odorless
R-134a color
Light Blue (Sky)
R-22 color
Light Green
A refrigerant that is classified as A1 has ___________.
Low toxicity and no flammability identified
When measuring low side pressure, a technician can use a pressure-temperature (P/T) chart to find__________
Low-side refrigerant's boiling temperature
A refrigerant lubricant made from refined crude oil and used only with CFCs and HCFCs describes _________ lubricants.
MO
Regarding pour point, a refrigeration lubricant should be selected based on a systems __________.
Operating temperature
R-404A color
Orange
Lubricants specifically designed for use with HFCs and are not recommended for use in compressors with aluminum pistons in steel cylinders describes ___________ lubricants
PAG
A group of synthetic lubricants compatible with CFC's, HCFCs, and HFCs describes _________ lubricants.
POE
R-410A color
Pink (Rose)
HFO refrigerant used in automotive air conditioning
R-1234yf
Popular HFC refrigerant used in domestic and commercial refrigeration and as a retrofit for R-12.
R-134a
HFC zeotropic blend used in medium and low temperature refrigeration.
R-404A
Zeotropic blend used to retrofit R-22 equipment
R-407C
HFC zeoptropic blend used in new air-conditioning equipment.
R-410a
Azeotropic blend used in low-temperature refrigeration.
R-508B
HC refrigerant commonly used in domestic refrigerations, freezers, and standalone equipment.
R-600a
The temperature of tubing in a refrigeration system is referred to as ___________ temperature
Skin
True or False? Even though some refrigerants, such as R-12 are illegal to manufacture, it is still legal to service units containing R-12.
True
A measure of liquid's resistance to flow is called _______.
Viscosity
R-12 color
White