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Recovery is removing refrigerant from an appliance and putting it into a container in any condition, with no processing. Recycling cleans it for reuse, and reclamation restores it to new-product purity verified against AHRI 700. Knowing these three definitions is one of the most tested exam topics.

Reclamation reprocesses refrigerant to new-product purity and verifies it by chemical analysis against the AHRI 700 standard. Only an EPA-certified reclaimer may do this. Recovery only removes and stores, and recycling cleans for reuse without a chemical purity check.

AHRI Standard 700, formerly ARI 700, defines the purity a refrigerant must meet, limiting moisture, acidity, non-condensables, and other contaminants, to be sold as reclaimed and equivalent to new product. Cylinder color and evacuation levels are set by other standards and EPA rules. Meeting AHRI 700 is what allows resale of reclaimed refrigerant.

Only an EPA-certified reclaimer may reprocess refrigerant to AHRI 700 purity and resell it. A certified technician can recover and recycle refrigerant but cannot legally reclaim and resell it. This distinction keeps resold refrigerant at a verified quality level.

Recovery and recycling equipment made on or after November 15, 1993 must be certified by an EPA-approved laboratory, such as UL or ETL, to meet EPA performance standards. Gray-and-yellow coloring applies to recovery cylinders, not the machine. Equipment does not have an automatic five-year replacement rule.

Self-contained equipment has its own compressor or pump and can pull refrigerant from any appliance without relying on the unit. System-dependent equipment has no pump and depends on the appliance's own pressure or compressor, so it may be used only on small appliances. Choose active equipment for high- and low-pressure work.

System-dependent equipment relies on the appliance's own pressure or compressor to move refrigerant, so it is limited to small appliances with five pounds or less of charge. Larger high- and low-pressure systems require self-contained equipment. Using passive equipment on a large system would not achieve the required recovery.

Recovered refrigerant must go into a DOT-approved refillable recovery cylinder, never a disposable one-trip cylinder, which is illegal and unsafe to refill. The cylinder must be within its hydrostatic test date and filled to no more than 80 percent. Proper cylinders prevent contamination and rupture.

Recovery cylinders are marked with a gray body and a yellow top or shoulder so they are not confused with containers of virgin refrigerant, which carry their own product-specific colors. This standard coloring helps prevent accidental cross-contamination. Always confirm a recovery cylinder is proper before filling.

Never fill a recovery cylinder beyond 80 percent of its capacity by weight. The remaining 20 percent of headspace lets the liquid refrigerant expand as temperature rises, preventing a hydraulically full cylinder from rupturing. Always weigh the cylinder to confirm the fill level.

An overfilled cylinder has no room for the liquid to expand, so a rise in temperature can make it hydraulically full and burst it, releasing refrigerant with great force. This is why the 80 percent limit and weighing are strict rules. Overfilling is one of the most serious cylinder hazards.

Identifying the refrigerant with a refrigerant identifier before recovery prevents pulling an unknown or contaminated charge into clean equipment or a partly filled cylinder. Mixing refrigerants can ruin a whole cylinder and the recovery machine. Identification protects both the equipment and the value of the recovered refrigerant.

A mixed refrigerant batch generally cannot be recycled or reclaimed to any standard, so it must be sent for destruction at a cost. This wastes refrigerant and money. To avoid it, identify refrigerant before recovery, use a dedicated cylinder per refrigerant, and evacuate equipment between refrigerants.

Recycling reduces a refrigerant's oil, moisture, and acidity using an oil separator and filter-driers so it can be reused, typically on-site or at a local shop, without a chemical purity analysis. Reclamation goes further, verifying AHRI 700 purity by chemical analysis. Recycled refrigerant generally stays with the same owner.

When refrigerant changes ownership, it generally must be reclaimed to the AHRI 700 standard by a certified reclaimer before resale. Refrigerant that stays with the same owner may simply be recycled and reused. This rule keeps resold refrigerant at verified new-product quality.

The recovery evacuation table sets required levels based on the appliance type and size and whether the recovery equipment was made before or after November 15, 1993. For example, low-pressure appliances require 25 mm Hg absolute, while a large HCFC-22 system requires 10 in Hg with newer equipment. Certification type and cylinder color do not set the vacuum level.

A refillable DOT recovery cylinder must be hydrostatically tested every five years, and the test date is stamped on the cylinder. Using a cylinder past its test date is unsafe and not permitted. Always confirm the test date before filling.

The fill level must be determined by weighing the cylinder on a scale, since the 80 percent limit is by weight. Pressure, sound, and temperature do not reliably show how full a cylinder is. Overfilling risks a hydrostatic rupture, so accurate weighing is essential.

Pulling liquid first moves the largest portion of the charge quickly, then vapor recovery finishes drawing the system down to the required level. This shortens the job significantly on a big system. It is a technique choice, not a cleaning or a legal recycling prerequisite.

Compliance recordkeeping includes proof that recovery equipment is certified, technician certification records, and, for larger appliances, records of refrigerant added during servicing. These documents protect the company during an EPA inspection. Good records also help ensure recovered refrigerant can be reclaimed later.

Disposable one-trip cylinders are designed to be used once and must never be refilled or used to store recovered refrigerant; refilling them is illegal and dangerous. Recovered refrigerant goes only into refillable DOT recovery cylinders. When empty and recovered, one-trip cylinders are rendered safe and recycled as scrap.

Passing refrigerant through filter-driers to reduce moisture and acidity, together with oil separation, is the essence of recycling refrigerant for reuse. Reclamation adds full chemical analysis to AHRI 700, and venting and retrofitting are unrelated. Recycling equipment is often combined with the recovery machine.

Between refrigerants, evacuate the recovery machine and hoses and use a separate, dedicated cylinder for each refrigerant to prevent cross-contamination. Reusing a cylinder or skipping identification can create a mixed batch that cannot be reclaimed. Clean separation preserves the refrigerant's value.

Low-loss fittings close off automatically to release as little refrigerant as possible each time you connect or disconnect hoses, cutting emissions on every job. They do not test purity, cool cylinders, or raise pressure. Using them is good conservation practice across all refrigerant work.

With post-1993 recovery equipment and a working compressor, a small appliance requires 90 percent recovery; if the compressor does not run, the requirement is 80 percent. The 4 in Hg vacuum is an accepted alternative for such equipment, and 25 mm Hg absolute applies to low-pressure appliances, not small ones.

Preventing air from entering the system, hoses, and cylinder during recovery keeps non-condensable gases low, which keeps pressure readings accurate and the refrigerant cleaner. Adding nitrogen or heating the cylinder would make the problem worse. Purging air and keeping fittings tight are the correct practices.

Recovery and recycling equipment is certified to EPA performance standards by approved laboratories such as Underwriters Laboratories (UL) or ETL. OSHA covers workplace safety and DOT covers cylinder transport, but neither certifies recovery-equipment performance. Look for the certification label when buying equipment.

Refillable recovery cylinders are typically built to DOT-4BA or DOT-4BW specifications, which are rated for repeated filling and periodic hydrostatic testing. DOT-39 is a non-refillable one-trip specification that must never be reused for recovery. Always confirm the cylinder is a refillable recovery type.

Refrigerant that stays with the same owner may be recycled on-site and returned to that owner's equipment without reclamation. Reclamation to AHRI 700 is required only when refrigerant changes ownership and is resold. Venting is always illegal.

A technician or company that acquires certified recovery equipment must certify to EPA that they have the equipment and will use it properly. Registration with DOT and gray-yellow paint apply to cylinders, not the machine, and there is no annual lab retest requirement. This self-certification is part of Section 608 compliance.

With post-1993 equipment, an HCFC-22 appliance of 200 pounds or more must be evacuated to 10 inches of mercury vacuum, while one under 200 pounds needs only 0 in Hg. The 25 mm Hg absolute level is for low-pressure appliances. Matching refrigerant, size, and equipment age to the number is a common exam task.

With many refrigerants in the field and counterfeit or mixed charges circulating, identifying refrigerant first protects your recovery machine and cylinder from contamination and preserves the refrigerant's value for reclamation. A mixed batch usually cannot be reclaimed and must be destroyed. A refrigerant identifier is a small investment against a costly mistake.

From least to most thorough, the order is recover (remove and store), recycle (clean for reuse), and reclaim (restore to new-product purity verified by chemical analysis). Recovery does the least processing and reclamation the most. Remembering this progression makes the definitions easy to keep straight.

Heat raises the pressure inside a cylinder, and an overfilled or very hot cylinder can rupture, which is why cylinders must stay below 125°F and be filled to no more than 80 percent. Store cylinders cool, upright, and secured. A hot trunk can push a marginal cylinder past its safe limit.

Recycling equipment with an oil separator and filter-driers reduces oil, moisture, and acidity so recovered refrigerant can be reused on-site with the same owner. Reclamation to AHRI 700 requires a certified reclaimer and is needed for resale. Venting is never allowed.

For other high-pressure refrigerants such as CFC-12, post-1993 equipment must evacuate an appliance under 200 pounds to 10 inches of mercury vacuum, and 200 pounds or more to 15 in Hg. HCFC-22 has its own lower numbers, and 25 mm Hg absolute is for low-pressure. Memorizing the table by refrigerant and size is essential.

The gray body and yellow shoulder identify a container as a recovery cylinder holding used or mixed refrigerant, keeping it visually separate from color-coded virgin refrigerant containers. This reduces the chance of accidentally charging a system with contaminated refrigerant. The color does not indicate empty, flammable, or disposal status.

Section 608 requires recovering refrigerant to the applicable evacuation level before opening an appliance for major service that breaches the sealed system or before disposal. Simply adding refrigerant or reading gauges does not trigger the requirement. The evacuation level depends on the appliance type and recovery-equipment age.

Keeping proof of technician certification, equipment certification, and servicing or refrigerant-addition records lets you demonstrate compliance if an EPA inspector asks. Recordkeeping does not set prices or replace the requirement for certified equipment. Complete, honest records are a technician's best protection during an inspection.

Recovery merely removes and stores refrigerant; recycling cleans it of oil, moisture, and acid for reuse without a purity test; and reclamation reprocesses it to AHRI 700 purity verified by chemical analysis, and only a certified reclaimer may do it. This layered definition is among the most frequently tested facts on the exam.