epa Flashcards
What is ODP and what does it do.
Ozone depletion potential measures the ability of a substance to destroy ozone in the stratosphere
how many ozone molecules can a single cholrine molecule destroy
100,000
what are HFCs
they are compounds made up of hydrogens fluoride and carbons
what is GWP
global warming potential
what GWP is used as a baseline measurement and what is its value
Carbon dioxide with a value of 1
what compounds have low GWP
Hydrocarbons and hydrofluoroolefin
true or false,Because Hydrofluoroolefin refrigerants are non depleting and have very low GWP this makes it a good fit for HVACR equipment
true
true or false, HFCs have very low GWP and are also good for the enviroment
false
true or false, when talking about safety identification for refrigerants Class B is the safe non toxic group.
false
true or false, when talking about flammability for refrigerants 1 indicates no flammability, 2 low flammability, 3 high flammability
true
What refrigerants have the highest ODP and are the most harmful to the environment
CFC refrigerants
What refrigerants have a ODP that ranges between 0 and 1
HCFC refrigerants
What refrigerants have little to no ODP but have a very small effect on global warming
HFC refrigerants
What refrigerants have no ODP and are mildly flammable
HFO refrigerants
What refrigerants are an elementary compound and pose the least danger to the environment.
HC refrigerants
What are azeotropic refrigerant
Mixtures that contain two or more refrigerants,
What are zeotropic refrigerants
Mixtures of components that have different boiling points Also called non-azeotropic
When charging by suction or evaporator superheat what values are used
dew point(vapor)
When charging by condenser sub cooling what values are used
bubble point(liquid)
What is the proper charging method for R400 series blended refrigerants
Weigh the refrigerant into the high side of the system as a liquid
true or false, The EPA does not approve any substitute refrigerants as direct drop-in replacements to serve an r-22 or any other system
true
Low pressure refrigerants have what pressure at 104degrees Fahrenheit
30 psig or lower
Medium pressure refrigerants have what pressure at 104degrees Fahrenheit
A pressure between 30psig-155 psig
high pressure temperature refrigerants have what pressure at 104degrees Fahrenheit
A pressure between 155psig- 340psig
very high pressure temperature refrigerants have what pressure at 104degrees Fahrenheit
A pressure above 340psig
what is the Montreal protocol
international treaty that addresses ozone-depleting substances and their alternatives
what refrigerants are starting to be phased out or have been phased out completely
CFCs and HCFCs
It is ____ to knowingly release CFC, HCFC or HFC refrigerants during the service, maintenance, repair, or disposal of appliances
illegal
true or false, A person is required to be a 608 certified technician when servicing an external electric circuit or sections of the system that do not involve the refrigerant components of an HVACR appliance
false
What does the clean air act allow to be used for leak detection
a small amount of refrigerant with mitrogen
By what year will all HCFC be phased out
2030
true or false, It is a violation of the refrigerant management regulations under the Clean Air Act after to service a system that uses phased out refrigerants
false
reclaimed refrigerant must meet what condition in order to be resold
It must meet the AHRI standard 700
_____- recovery devices remove refrigerant from an appliance without the assistance of components in the appliance
self contained
_____- recovery devices remove refrigerant from an appliance with the assistance of components in the appliance
system dependent
The EPA requires appliances that do not have service valves to contain a _____
service aperture or process stub
When disposing appliances with ______ pounds of refrigerants technicians are not required to record the model and serial number of the appliance
5-50
Record that need to be kept when recovering refrigerant are?
type of refrigerant, quantity of refrigerant, quantity recovered from disposed appliances in each calendar month, and quantity of refrigerant sent for reclamation or destruction
true or false, Natural refrigerants such as carbon dioxide need to be purchased by someone who is section 608 certified
false
true or false, it is unlawful to service R22 systems and use existing supplies of R22
false
true or false, it is not legal to top off an R22 charge with another refrigerant such as R410a
true
What is the proper way to discard disposable cylinders of CFCs, HCFC, HFCs. or HFO
recover all remaining refrigerant, render the cylinder useless, and recycle the metal
what needs to be done before disposing any appliance containing a CFC, HCFC, or HFC refrigerant
Refrigerant must be recovered to the EPA recovery or evacuation levels
According to the safe disposal requirements the final person in the disposal chain is responsible for what
Ensuring that any CFC,HCFC, or HFC refrigerant has been removed from household refrigerators or other appliances before they are disposed of
Knowingly releasing ____________ refrigerant during service, maintenance, repair, etc is illegal
CFC, HCFC, HFC, HFO
true or false, venting refrigerant from a recovery machine or recovery cylinder after use is legal
false
true or false, records of recovered refrigerant must be kept to ensure venting does not take place after recovery from an appliance
true
Small quantities of _____ used in household freezers can be vented
isobutane
true or false, releasing mixtures of nitrogen and refrigerant that result from adding nitrogen to a full charged system to leak check it is considered a violation of the prohibition on venting
true
How much refrigerant has to be added to nitrogen in order for it to be considered a leak trace gas
Only a few ounces
What does it mean to recover?
To remove refrigerant in any condition from a system and store it in an approved recovery cylinder or container.
True or false, Recovered refrigerant may not be charged into the same system, or into another system with the same ownership
false
What does it mean to recycle
means to extract refrigerant from an appliance and clean the refrigerant for reuse in equipment of the same owner without meeting all of the requirements for reclamation
when recycling refrigerant from an appliance, does it apply to motor vehicle air conditioner or MVACs as well.
no they are exempt from this
How is refrigerant cleaned
It is cleaned by using oil separation and single or multiple passes through devices such as core filter driers to remove particulate matter
Recycling equipment must meet this requirement in order to be used
They must meet the AHRI 740 performance ratio standard
what does it mean to reclaim
to process refrigerant o a level equal to new product specifications as determined by chemical analysis
true or false reclaiming is usually preformed at a chemical processing company
true
Refrigerant recovery and/or recycling equipment manufactured after ______ must be certified and labeled by an EPA approved equipment testing organization to meet EPA standards
November 15,1993
What is required on all new recovery equipment
EPA approved certification label
What are the two types of recovery devices
System dependent, and self contained
The recovery time will be ____ if the appliance is located in low ambient temperature or long hoses are used between the unit and the recovery machine
increased
What should be type of hoses should be avoided when connecting the unit to the recovering machine
long and small diameter hoses
why do long and small diameters need to be avoided
They cause excessive pressure drop and increase recovery time
What needs to be done upon the completion of refrigerant liquid transfer between the recovery unit and the refrigerant system
A technician must guard against the trapping of liquid refrigerant in the service hose between closed service valves
The technician must have a ____ refrigerant recovery cylinder for each type of refrigerant recovered
separate
true or false it is okay to have a single cylinder for refrigerants that are known to be mixed
false
How many cylinders are required if you are servicing a system that uses HFC-134a, HFC410a, and HCFC-22
3
true or false it is fine for someone to mix refrigerants in the same containers when recovering refrigerants
false
what happens when refrigerants are mixed
They maybe impossible to reclaim and there maybe an additional cost to have them destroyed
In order for used refrigerant to change ownership what needs to be done
They need to be reclaim and pass the AHRI standard for virgin refrigerant
true or false, it is okay for you to use any leak detector with flammable refrigerant
False
What is the most effective way to determine the general area of a leak
Using an electronic or ultrasonic leak detector
Newly installed systems should be pressurized with______ for leak detection purposes
dry-nitrogen
true or False, the trace gas can be different than the refrigerant the appliance is going to be charged with
false
true or false, a leak trace gas is considered a refrigerant
false
what should a technician do upon the completion of a leak repair
install a new filter drier and complete a standing pressure leak check at the maximum system pressure
Any system designed t0 contain a flammable HC or HFO refrigerant has to have a ____ before evacuating to 500 microns or less
leak test
true or false, Odarants need to be added to a system containing flammable refrigerants
false
What does it mean to dehydrate a refrigeration system
To remove water and water vapor from the system
What occurs if water and water vapors are allowed to remain in a system
Hydrochloric and hydrofluoric acids may form
true or false, it is possible to over evacuate a system
false
What do most manufacturers require a system evacuation to be
500 microns or less
true or false, never evacuate a system to the ambient air without first following props recovery procedures and attaining the mandated recovery level required by the EPA regulations
true
What are the factors that affect the speed and efficiency of evacuation
ambient temperature, amount of moisture n the system, size of the vacuum pump and vacuum lines
Vacuum lines should be ______ than the pump intake connections
equal to or greater than
true or false, the way a micron gauge is connected may affect the speed of evacuation
true
the piping connection to the vacuum pump should be as ____ in length as possible and as ___ in diameter as possible
short;long
How do you get accurate readings during an evacuation
The system vacuum gauge should be as far away from the vacuum pump as possible
a system that can not hold a vacuum most likely has what
a leak
What may a technician do to speed up dehydration time
They may heat up the system
What may a technician do to release refrigerant trapped in oil
tap the compressor with a mallet
what is an indicator that moisture is still stuck in the system
if the pressure rises, stops, and then continues to rise
A refrigerant recovery cylinder should not be filled more than __ of its capacity by weight
80%
How do you identify refrigerant recovery cylinders
they have gray bodies with a yellow colored top
true or false the pitch of the recovery device controls the fill level of the recovery cylinder
false
true or false a disposable refrigerant cylinder may be used to recover refrigerant
false
when shipping used refrigerants what needs to be placed on the cylinders
A refrigerant label to identify the type of refrigerant to avoid accidental mixing
What do DOT Regulations require
the number of cylinders be recorded on the shipping papers for hazard class 2.2 nonflammable compressed gases
What position do refrigerant cylinders need to be in when they are shipped
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