EPA 608 Book Exam CORE SECTION A GENERAL KNOWLEDGE
All refrigerant recovery cylinders should be inspected for
Rust and if they show signs of rust or appear to not be secure they should be reduced to 0 psig and discarded.
The stratosphere is the Earth's security blanket is located
between 10 and 30 miles above sea level and is comprised of, among other things, Ozone
One type of recovery equipment is referred to as System-dependent
captures refrigerant with the assistance of components in the appliance from which refrigerant is being recovered
In the event of a 'large" release of refrigerant in a confined area what is required?
Self Contained Breathing Apparatus (SCBA) is required.
The second type of recovery equipment is Self-contained
has its own means to draw the refrigerant out of the appliance
NEVER expose R-12 or R-22 to
high temperatures, open flames or glowing hot metal surfaces.
If moisture is allowed to remain in an operating refrigeration system what may form?
hydrochloric and hydrofluoric acids may form
Approved refrigerant recovery cylinders can easily be identified by what colors
YELLOW TOPS AND GRAY BODIES
Can R-134A be used in most R-12 systems
Yes, by following appropriate retrofit procedures.
If a strong odor is detected during the recovery process what has likely occurred
a compressor burn-out
EPA regulations require what for Class I&II refrigerant in order to make it easier to recover refrigerant.
a service aperture or process stub on all appliances that use a Class I & II
What are the factors affecting the speed and efficiency of evacuation?
size of equipment being evacuated ambient temperature amount of moisture in the system the size of the vacuum pump and suction line
When servicing a system, if you discover that two or more refrigerants have been mixed in a system what must be done?
you must recover the mixture into a separate tank
Refillable cylinders must be hydrostatically tested and date stamped every how many years?
5 years
Other blends may be azeotropic.
An azeotropic mixture that acts like a single component refrigerant over its entire temperature / pressure range. An azeotrope does not have a temperature glide.
Montreal Protocol called for
CFC's were phased out of production on December 31, 1995
Some states may require special shipping procedures to be followed based on their classification of used refrigerants.
Check with the DOT in the state of origin.
Refillable cylinders used for transporting recovered pressurized refrigerant must be approved by?
DOT (Department of Transportation) approved.
What is the suggested method of dehydration
Evacuation of a system
There is some specific information you will need to know about blends.
First, the components of a blended refrigerant will leak from a system at uneven rates due to different vapor pressures. Second, the proper charging method for blended refrigerants is to weigh into the high side of the system as a liquid.
R-12 and R-22 decompose to form
Hydrochloric acid, Hydrofluoric acid, and Phosgene gas
If a large leak of refrigerant occurs in an enclosed area, and SCBA is not available
IMMEDIATELY VACATE AND VENTILATE the area.
How does the length of the hose between the unit being recovered from and the recovery machine effect the efficiency of the recovery process.
Long hoses will cause excessive pressure drop, increased recovery time, and have a potential for increased emissions
CFC R-12 retrofit which refrigerant is the leading candidate
R-134A
RECOVERY DEVICES
Refrigerant Recovery and/or Recycling equipment manufactured after November 15, 1993, must be certified and labeled by an EPA approved equipment testing organization to meet EPA standards. There are two basic types of recovery devices.
Can relief valves be installed in series?
No
Is R-134A a drop-in substitute for CFC R-12
No
Since what date has the sale of CFC and HCFC refrigerants been restricted to certified technicians.
November 14, 1994
Who is allowed to purchase refrigerants in containers smaller than 20 lbs.
Only technicians certified under Clean Air Act Section 609—Motor Vehicle Air Conditioning
There are four (4) categories of technician certification
TYPE I Persons who maintain, service or repair small appliances must be certified as Type I technicians. TYPE II Persons, who maintain, service, repair or dispose of high or very high-pressure appliances, except small appliances and motor vehicle air conditioning systems, must be certified as Type II technicians. TYPE III Persons, who maintain, service, repair, or dispose of low-pressure appliances must be certified as Type III technicians. UNIVERSAL Persons, who maintain, service or repair both low and high-pressure equipment, as well as small appliances, must be certified as Universal technicians.
What is "temperature glide"
Temperature glide refers to a refrigerant blend that has a range of boiling points or condensing points throughout the evaporator and condenser respectively
Why causes a slower the recovery rate.
The lower the ambient temperature, since all refrigerants have a pressure temperature relationship
The layer of the Stratosphere that protects us from excessive Ultra Violet radiation is comprised of
The stratosphere is the Earth's security blanket. It is located between 10 and 30 miles above sea level and is comprised of, among other things, Ozone
When leak checking a system, NEVER pressurize the system with oxygen or compressed air.
True
When mixed with refrigerants, oxygen or compressed air can cause an explosion.
True
vacuum lines should be equal to or larger than the pump intake connection
True
THE THREE "R's"
To RECOVER is to remove refrigerant in any condition from a system and store it in an external container. To RECYCLE is to clean refrigerant for rouse by separating the oil from the refrigerant and removing moisture from the refrigerant by passing it through one or more filter driers. To RECLAIM is to process refrigerant to a level equal to new (virgin) product specifications as determined by chemical analysis. RECLAIMED refrigerant must meet the standard set forth in ARI 700 before it can be resold.
A single Chlorine atom can destroy 100,000 Ozone molecules.
True
A system that will not hold a vacuum probably has a leak
True
CFC's and HCFC's, when released into the atmosphere deplete the Ozone layer.
True
CFC's have been found in air samples taken from the stratosphere
True
CFC's have the highest ODP
True
Cylinders should be transported in an upright position.
True
Dehydration is complete when the vacuum gauge shows that you have reached and held the required finished vacuum
True
During evacuation you may wish to heat the refrigeration system to decrease dehydration time
True
Each cylinder must be marked with a DOT classification tag indicating it is a "2.2 non-flammable gas".
True
HCFC refrigerants are scheduled of phase out in the future. When virgin supplies of CFC's are depleted, future supplies will come from recovered, recycled, or reclaimed refrigerants.
True
HFC's (R-134A) do not contain chlorine and have no Ozone Depletion Potential
True
In CFC's and HCFC's, chlorine in these compounds is the culprit that damages the Ozone
True
In large quantities, refrigerants can cause suffocation because they are heavier than air and displace oxygen.
True
Inhaling refrigerant vapors or mist may cause heart irregularities, unconsciousness, and oxygen deprivation leading to death (asphyxia).
True
It is not possible to over evacuate a system
True
Measuring a systems vacuum should be done with the system isolated and the vacuum pump turned off
True
Never evacuate a system to the ambient air without first following proper recovery procedures and attaining the mandated vacuum level.
True
Ozone Depletion Potential (ODP) is a measurement of CFC's and HCFC's ability to destroy ozone
True
Ozone protects us from harmful ultraviolet radiation and helps maintain stable Earth temperatures.
True
R-134A is a HFC and is considered Ozone friendly
True
Recovery cylinders have 2 ports, one liquid and one vapor
True
Stratospheric Ozone depletion is a global problem
True
The EPA requires that a refillable refrigerant cylinder MUST NOT BE FILLED ABOVE 80% of its capacity by weight, and that the safe filling level can be controlled by either mechanical float devices, electronic shut off devices (thermistors), or weight
True
The piping connection to the pump should be as short a length as possible and as large in diameter as possible
True
The system vacuum gauge should be connected as far as possible from the vacuum pump
True
When a chlorine atom meets with an Ozone molecule, it takes one Oxygen atom from the Ozone. This forms a compound called Chlorine Monoxide (CIO) and leaves an O2 molecule. The Chlorine Monoxide will collide with another Ozone molecule, release its Oxygen atom, forming two O2 molecules, and leave the chlorine free to attack another Ozone molecule.
True
When pressurizing a system with nitrogen, you should always?
charge through a pressure regulator and insert a relief valve in the downstream line from the pressure regulator.
What must be done before shipping any used refrigerant cylinders?
check that the cylinder meets DOT standards, complete the shipping paperwork including the number of cylinders of each refrigerant, and properly label the cylinder with the type and amount of refrigerant.
How do you determine the safe pressure for leak testing
check the data plate for the low-side test pressure value.
The molecule found in CFC's and HCFC's that depletes ozone is:
chlorine
What are disposable cylinders used for?
only with virgin refrigerant and may NEVER be used for recovery
When leak testing an R-134A system what must be used
pressurized nitrogen
After recovering refrigerant, if nitrogen is used to flush debris out of the system what may be done?
the nitrogen may be vented
What must be done if corrosion buildup is found within the body of a relief valve
the valve MUST be replaced
Ozone molecule consists of
three oxygen atoms (03)
What is the reason for dehydrating a refrigeration system
to remove water and water vapor
Why should a suction line filter drier should be installed on a new compressor
to trap any debris that may damage the new compressor.
Depletion of Ozone in the stratosphere causes:
♦ CROP LOSS ♦ INCREASE IN EYE DISEASES ♦ SKIN CANCER ♦ REDUCED MARINE LIFE ♦ DEFORESTATION ♦ INCREASED GROUND LEVEL OZONE
It is a violation of Section 608 to:
♦ Falsify or fail to keep required records; ♦ Fail to reach required evacuation rates prior to opening or disposing of appliances; ♦ Knowingly release (vent) CFC's, HCFC's or HFC's while repairing appliances, with the exception of de-minimus releases; ♦ Fail to recover CFC's, HCFC's or HFC's before opening or disposing of an appliance; ♦ Fail to have an EPA approved recovery device, equipped with low loss fittings, and register the device with the EPA; ♦ Add nitrogen to a fully charged system, for the purpose of leak detection, and thereby cause a release of the mixture; ♦ Dispose of a disposable cylinder without first recovering any remaining refrigerant (to 0 psig.) and then rendering the cylinder useless, then recycling the metal;
It is a violation of Section 608 to:
♦ Service, maintain, or dispose of appliances designed to contain refrigerants without being appropriately certified as of November 14, 1994. (It is the responsibility of the final person in the disposal chain to ensure that refrigerant has been removed from appliances before scrapping.)
It is a violation of Section 608 to:
♦ Vent CFC's or HCFC's since July 1, 1992;
It is a violation of Section 608 to:
♦ Vent HFC's since November 15, 1995;