EPA Core

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Recovery Cylinders

If a refillable cylinder shows signs of rust or appears to have been heated or damaged in any way, it should be reduced to 0 psig by recovering to another cylinder and discarded. Reclaimers will not accept visibly burned recovery tanks.

Recovery Techniques

It is important NOT to mix different refrigerants in the same recovery tank because the mixture may be impossible to reclaim. Recover only one type of refrigerant into a recovery tank. The number of recovery tanks required by a person or company depends on the variety of equipment worked on and their types of refrigerants.

Carbon dioxide (CO2):

. Carbon Dioxide is used as a very high-pressure refrigerant (R-744) with zero (0) ODP and a Global Warming Potential (GWP) of one (1). R-744 is used primarily in commercial and industrial process systems and does not require Section 608 certification for purchasing or servicing

There are two basic types of recovery devices:

1) "System-dependent" which captures refrigerant with the assistance of components in the appliance from which refrigerant is being recovered. 2) "Self-contained" which has its own means to draw the refrigerant out of the appliance.

ASHRAE

American Society of Heating, Refrigerating and Air-Conditioning Engineers. grouped refrigerants by Class A (safest) or B, depending on their toxicity level to humans. Flammability is indicated by a 1 (no flammability), 2 (low flammability), or 3 (high flammability).

Carbon dioxide (CO2):

CO2 is a natural gas, created through respiration and absorbed through photosynthesis, a relatively balanced cycle. The addition of man-made CO2 creates an overabundance and results in excess GHGs that enter the atmosphere as a result of burning fossil fuels (coal, natural gas, and oil), solid waste, wood/products, and is the result of certain chemical reactions such as cement manufacturing

Clean Air Act

Companies and or service technicians who violate Clean Air Act provisions may lose their certification, be required to appear in Federal Court and be fined up to $44,539 per day, per violation. The EPA may require technicians to demonstrate the ability to properly perform refrigerant recovery/recycling procedures. Failing to demonstrate these skills can result in revocation of certification. State and local jurisdictions may impose regulations that are equal to or greater than those under the EPA's Section 608

Flammable refrigerants

Equipment with flammable refrigerants requires a red color marking on all process tubes, service connections, and pipes through which a flammable refrigerant passes. When propane (R-290) is used as refrigerant, it must meet the purity standards set for HVACR equipment. Propane and Isobutane are examples of "A3" flammable refrigerants that do not require recovery. Propane, Butane and other Hydrocarbon refrigerants are also known as HC refrigerants

Dehydration

Evacuation of a system is the suggested method of dehydration. It is not possible to over evacuate a system. Most manufacturers require an evacuation to 500 microns or lower which can be measured with a micron gauge

Fluorinated gases

Hydrofluorocarbons, perfluorocarbons, sulfur hexafluoride, and nitrogen trifluoride are synthetic, powerful greenhouse gases that are emitted from a variety of industrial processes. Fluorinated gases such as CFCs, HCFCs and HFCs are referred to as high Global Warming Potential gases ("High GWP gases").

Ozone Depletion Potential

Ozone Depletion Potential (ODP) is a measurement of a substance such as CFC's and HCFC's ability to destroy ozone, and ranges from 0 to 1. CFCs have the highest ODP. HFCs (Hydrofluorocarbons/R-134a, R-32, & 400 series blends) and HFOs (hydrofluoroolefins/ R-1234yf, 1234ze & 1233zd) do not contain chlorine and have an Ozone Depletion Potential of zero.

R-1234yf: (Tetrafluoropropene)

R-1234yf is a medium pressure, HFO refrigerant with an (ODP) of 0 and global warming potential (GWP) only 4 times greater than carbon dioxide.

gauge manifold set

The left side, compound gauge (blue) and the right side, high-pressure gauge (red), are attached to the manifold to measure system pressures. Hoses are used to connect the manifold to the refrigeration system's access ports or service valves to gain access to system pressures.

Dehydration

The reason for dehydrating a refrigeration system is to remove water and water vapor and it is important to follow proper dehydration procedures. If moisture is allowed to remain in an operating refrigeration system, hydrochloric and hydrofluoric acids may form.

Sales Restriction

The sale of CFC and HCFC refrigerants has been restricted to certified technicians since November 14, 1994. The sale of HFC and HFO refrigerants are restricted to certified technicians as of January 1, 2018.

Leak Detection

an electronic or ultrasonic leak detector after pressurizing the system with nitrogen and a trace amount of refrigerant. Once the general area of the leak is located, the use of soap bubbles will aid in pinpointing the leak.

Montreal Protocol

an international agreement (treaty) regulating the production and use of CFCs, HCFCs, halons, methyl chloroform and carbon tetrachloride entered into force in mid-1989.

Stratospheric Ozone Depletion

caused by ozone-depleting chemicals (ODCs) such as CFCs, methyl chloroform or trichloromethane (CHCl3), carbon tetrachloride (CCl4), halon (haloalkanes), methyl bromide (CH3Br)— all of which attack stratospheric ozone. The Cl or Br atoms "attack" the ozone molecules and cause the thinning of this layer. Global Agreement to decrease ODC - Montreal Protocol (1987)

Carbon dioxide (CO2)

created through respiration and absorbed through photosynthesis, a relatively balanced cycle.The addition of man-made CO2 creates an overabundance and results in excess GHGs that enter the atmosphere as a result of burning fossil fuels (coal, natural gas, and oil), solid waste, wood/products, and is the result of certain chemical reactions such as cement manufacturing

R-410A

is a high-pressure, HFC refrigerant with an ODP of zero (0) and global warming potential (GWP) 2,090 times greater than carbon dioxide. R-410A is a near azeotrope refrigerant that does not fractionate during phase change in HVACR equipment. One disadvantage of R-410A is the operating pressure is approximately 50% higher than R-22 and cannot be considered as a replacement for retrofitting existing systems.

R-134a: (Tetrafluoroethane)

is an HFC with an ozone depletion potential (ODP) of zero (0) and global warming potential (GWP) 1,430 times greater than carbon dioxide. R-134a is a medium-range pressure refrigerant used in auto, domestic refrigeration and commercial industries.

stratosphere

located between 7 and 30 miles above sea level, is comprised of ozone and other gases. The ozone layer is the Earth's security blanket. An ozone molecule, (O3), which consists of 3 oxygen atoms, protects us from harmful ultraviolet radiation from the Sun, and helps maintain stable Earth temperatures

The Three Rs (Recover - Recycle - Reclaim)

Recover: Remove refrigerant, in any condition, from a system and store it in an external container to be put back into the same system, recycled, or reclaimed. Recycle: Clean refrigerant by separating the oil from the refrigerant and removing moisture and other contaminants from the refrigerant by passing it through one or more filter driers. Recycled refrigerants may be placed back into the same system they came from or another system that is owned by the same owner. Reclaim: Process refrigerant to a level equal to new (virgin) product specifications as determined by chemical analysis. Reclaimed refrigerants must meet AHRI 700 Standards before they can be reused or sold to another user.

Recovery Cylinders

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 mechanical float d evices, electronic shut off devices (thermistors), or weight. Refillable cylinders must be hydrostatically tested and date stamped every 5 years.

CFCs (chlorine, fluorine & carbon) and HCFCs, (hydrogen, chlorine, fluorine & carbon)

When CFCs and HCFCs, are released into the atmosphere their chlorine content causes depletion of the ozone layer. When a chlorine atom encounters an ozone molecule, it takes one Oxygen atom from the ozone forming a compound called chlorine monoxide (CIO), leaving an oxygen O2 molecule behind. The chlorine monoxide will collide with another ozone molecule, releasing its Oxygen atom, forming two O2 molecules, leaving the chlorine free to attack another ozone molecule. A single chlorine atom can destroy up to 100,000 ozone molecules.

Safety

When handling and filling refrigerant cylinders or operating recovery or recycling equipment, you should wear safety glasses, protective gloves, and follow all equipment manufacturer's safety precautions. Make sure your recovery machine is grounded when in use, especially when recovering a flammable refrigerant.

Leak Detection

When leak testing any flammable hydrocarbon or HFO refrigerant, install a fresh filter-drier and complete a standing-pressure leak check at the maximum system pressure before evacuating to 500 microns or lower


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