Ozone depletion is caused by _______ in HFC refrigerants. - ANSWER chlorine
CFCs and HCFCs ________ making them capable capable of reaching the stratospheric ozone layer. - ANSWER do not dissolve in water or easily br
...
Ozone depletion is caused by _______ in HFC refrigerants. - ANSWER chlorine
CFCs and HCFCs ________ making them capable capable of reaching the stratospheric ozone layer. - ANSWER do not dissolve in water or easily break down in the atmosphere
According to the Rolanda-Molina theory, ________ are destroyed by each chlorine atom in the stratosphere. - ANSWER 100,000 ozone molecules
The stratospheric ozone layer protects us from _______. - ANSWER ultraviolet radiation from the sun
Which health effect increases from loss of the stratospheric ozone layer? - ANSWER cases of cataracts or skin cancer
What proves that HCFCs are in the stratosphere? - ANSWER HCFCs found in air samples from the stratosphere.
What makes HFC refrigerants damaging to the environment? - ANSWER They can have very high global warming potentials.
_______ makes HFO refrigerants less flammable than HC refrigerants. - ANSWER Flourine
Which refrigerant contains chlorine? - ANSWER R-12
HFO refrigerants are miscible in _______ lubricants. - ANSWER POE lubricants
An example of HcFC refrigerant is: ______ - ANSWER R-123
What is being done in the U.S. to stop damage to the stratospheric ozone layer? - ANSWER Eliminating the use of CFCs and HCFCs refrigerants
EPA regulations require appliances to have _________. - ANSWER a service aperture or process hub
The release of any CFC, HCFC, or HFC refrigerant during _________ is illegal. - ANSWER theft of equipment
____________ is the only EPA SNAP approved "drop in" replacement for
R-22. - ANSWER There are no direct drop-in refrigerant substitutes
Ester-based oils like POE can be mixed with ________. - ANSWER no other oils
What provides the cooling in a vapor compression refrigeration system? - ANSWER The vaporization of the liquid refrigerant
An oil sample might be taken when __________. - ANSWER a. moisture and/or acid problems are suspected
b. oil sludge formation or oil waxing is suspected
c. residual acidic oil from a burn-out is suspected of contaminating the replacement oil
________ returns refrigerant to new product specifications and requires chemical analysis to verify the purity to AHRI-700 standards. - ANSWER reclaiming
The EPA considers _________ the most effective for locating the general area of a small leak. - ANSWER electronic or ultrasonic tester
Low ambient temperatures __________ recovery time. - ANSWER increase
A system is considered dehydrated when _________. - ANSWER a micron gauge shows you have reached and held a vacuum of 500 microns or less with the vacuum pump isolated from the system
If corrosion is discovered in the body of a relief valve, the valve must be _______. - ANSWER replaced
The fill level of a recovery cylinder can be determined by __________. - ANSWER a. mechanical-float or electronic shut-off devices
b. the weight of the cylinder
Before recharging any flammable hydrocarbon or HFO refrigerant, always ___________. - ANSWER a. electronically ground the recovery machine and recovery tank, and verify the refrigeration system is grounded
b. install a fresh filter drier, successfully complete a
standing-pressure leak
A small appliance is defined as a system that is __________. - ANSWER manufactured, fully charged, and hermetically sealed in a factory with a charge of 5 pounds or less
__________ is an approved refrigerant for new household refrigerators, freezers, and combination refrigeration/freezers. - ANSWER R-600a
The hydrocarbon refrigerant approved for retrofit into existing household refrigerators is __________. - ANSWER none.
Hydrocarbons are not approved for any retrofit applications
Recovery devices for use with small appliances must be capable of ________. - ANSWER recovering 90% of the refrigerant when's the compressor is operating
Recovery equipment is certified by _________. - ANSWER an EPA-approved laboratory
When recovering refrigerant from small appliances, you must recover _________. - ANSWER at least 80% of the refrigerant with an inoperative compressor and 90% of the refrigerant with an operative compressor
The sale of reclaimed CFC, HCFC, HFC, and HFO refrigerants is ___________. - ANSWER restricted to technicians who are EPA certified in refrigerant recovery
A process stub is a ________. - ANSWER straight piece of tubing that is entered using a piercing access valve
Small appliance servicing requires a _________ or Universal certification. - ANSWER Type I
If a recovery cylinder is suspected to be contaminated, measure the ___________. - ANSWER pressure of the refrigerant in the cylinder
You must know the ___________ before beginning a refrigerant recovery. - ANSWER type of refrigerant that is in the system
When installing an access fitting, _____________. - ANSWER the fitting should be verified as leak free before beginning any recovery to avoid drawing air into the recovery tank
A passive system-dependent recovery process _________. - ANSWER uses a non-pressurized container
When recovering refrigerant using a passive recovery system and the system has an inoperative compressor, it is __________. - ANSWER helpful to heat and stretch the compressor with a rubber mallet to release any refrigerant trapped in and under the compressor oil
What requires access in both the high and low side of the system for refrigerant recovery when using a passive recovery process? - ANSWER when the compressor does not run
What is the pressure of a storage cylinder of R-134a, that is stored in a room where the temperature is 100 °F? - ANSWER 124 psig
Recovery of refrigerant cannot begin if the initial pressure in the system is _______.
[Show More]
