Refrigerant Recovery & Reclamation: EPA 608 Essential Procedures

Refrigerant recovery and reclamation are fundamental skills every EPA 608-certified technician must master. Understanding proper recovery procedures, evacuation requirements, and the difference between recovery, recycling, and reclamation is critical for both passing your certification exam and performing compliant, safe HVAC work.

The Three R's: Recover, Recycle, Reclaim

EPA Section 608 regulations establish three distinct processes for handling used refrigerants. Understanding the differences is essential for proper compliance and exam success.

Recover: Removing Refrigerant from Systems

Definition: To remove refrigerant in any condition from an appliance and store it in an external container without necessarily testing or processing it in any way.

Recovery is the most basic refrigerant handling operation. When you connect your recovery machine and remove refrigerant from an air conditioning system or refrigeration unit, you are performing recovery. The refrigerant is simply removed and placed into a DOT-approved recovery cylinder - nothing more.

Key characteristics of recovery:

• No cleaning or processing of the refrigerant
• Refrigerant condition is unknown - may contain moisture, acids, oil, or contaminants
• Must be stored in DOT-approved recovery cylinders (yellow body with gray top)
• Can be returned to the same system or another system owned by the same person
• Required before opening any system for maintenance, service, repair, or disposal
• Must use EPA-certified recovery equipment manufactured after November 15, 1993

Recycle: On-Site Cleaning for Reuse

Definition: To extract refrigerant from an appliance and clean refrigerant for reuse without meeting all requirements for reclamation. Generally involves oil separation and filtering to reduce moisture, acidity, and particulate matter.

Recycling involves processing recovered refrigerant through basic cleaning steps before returning it to service. Most recovery machines have built-in recycling capabilities including oil separators and filter-driers.

Recycling process typically includes:

• Oil Separation: Removing compressor oil mixed with refrigerant
• Moisture Removal: Passing refrigerant through replaceable filter-driers
• Particulate Filtering: Removing solid contaminants and debris
• Non-Condensable Removal: Purging air and other gases

Important limitations of recycling:

• Only suitable for returning refrigerant to equipment owned by the same person
• Cannot guarantee complete contaminant removal
• Not tested for purity - quality is unknown
• May not meet virgin refrigerant specifications
• Under EPA 609 (motor vehicle AC), can be charged into a different car after recycling

Reclaim: Reprocessing to Virgin-Grade Purity

Definition: To reprocess refrigerant to at least the purity specified in AHRI Standard 700-2016 and to verify this purity using the analytical methodology prescribed in the standard.

Reclamation is the only process that restores used refrigerant to virgin-grade quality. It involves sophisticated chemical analysis and processing that cannot be performed on-site.

Reclamation requirements:

• Must be performed by EPA-certified reclamation facilities - technicians cannot reclaim refrigerant on-site
• Chemical analysis required: Testing for water content, acidity, chlorides, non-condensables, volatile impurities
• Processing to AHRI 700-2016: Distillation, filtration, drying, and chemical treatment
• Verification testing: Laboratory confirmation of purity specifications
• Identifies contaminated refrigerant: Bad or mixed refrigerants that must be destroyed

When reclamation is required:

• Before selling used refrigerant to a new owner (federal law)
• When refrigerant will be charged into equipment owned by a different company
• When refrigerant is suspected to be contaminated or mixed
• For commercial refrigerant resale or redistribution

AHRI Standard 700-2016: The Reclamation Benchmark

The Air-Conditioning, Heating, and Refrigeration Institute (AHRI) Standard 700 establishes purity specifications for both new and reclaimed refrigerants. The EPA references AHRI Standard 700-2016 as the minimum purity requirement for reclaimed refrigerants sold to new owners.

What AHRI Standard 700 Covers

• Purity Requirements: Maximum allowable levels of contaminants regardless of refrigerant source
• Test Procedures: Analytical methods for verifying refrigerant composition and purity
• Acceptable Refrigerants: Standards for single-component, azeotropic blend, and zeotropic blend refrigerants
• Contaminant Limits: Specifications for water content, acidity, chlorides, non-condensables, volatile impurities

Key Contaminants Tested in AHRI 700

• Water (Moisture): Measured in parts per million (ppm) by weight - causes ice formation, acid development, and copper plating
• Acidity: Measured in ppm by weight - attacks metals and insulation, reduces compressor life
• Chloride Ions: Indicate refrigerant decomposition - cause corrosion and system damage
• Non-Condensable Gases: Measured as % by volume - reduces system efficiency and increases head pressure
• Volatile Impurities: Other refrigerants and hydrocarbons - affect system performance and safety

Reclaimed refrigerant meeting AHRI 700 specifications is chemically identical to virgin refrigerant and suitable for use in any compatible system without risk of contamination or performance degradation.

Required Evacuation Levels: Before and After November 15, 1993

EPA regulations specify minimum evacuation levels that technicians must achieve when recovering refrigerant. These requirements changed significantly on November 15, 1993, when the EPA implemented stricter standards and required certification of recovery equipment.

Small Appliances (Type I) Evacuation Requirements

Small appliances are defined as containing 5 pounds or less of refrigerant, factory-charged and hermetically sealed.

Equipment Manufactured	Working Compressor	Non-Working Compressor
Before Nov 15, 1993	80% of refrigerant OR 4 inches Hg vacuum	80% of refrigerant OR 4 inches Hg vacuum
After Nov 15, 1993	90% of refrigerant OR 4 inches Hg vacuum	80% of refrigerant OR 4 inches Hg vacuum

High-Pressure Systems (Type II) Evacuation Requirements

High-pressure systems use refrigerants with saturation pressures between 170-355 psia at 104°F (R-22, R-410A, R-404A, etc.).

System Charge Size	Before Nov 15, 1993	After Nov 15, 1993
Less than 200 lbs	4 inches Hg vacuum	0 psig (atmospheric)
200 lbs or more	4 inches Hg vacuum	10 inches Hg vacuum

Very High-Pressure Systems (Type II) Evacuation Requirements

Very high-pressure systems use refrigerants with saturation pressures above 355 psia at 104°F (R-13, R-23, R-503).

Equipment Manufactured	Required Evacuation Level
Before Nov 15, 1993	4 inches Hg vacuum
After Nov 15, 1993	0 psig (atmospheric pressure)

Low-Pressure Systems (Type III) Evacuation Requirements

Low-pressure systems operate below atmospheric pressure and typically use R-11 (legacy) or R-123 in large centrifugal chillers.

Equipment Manufactured	Required Evacuation Level
Before Nov 15, 1993	25 inches Hg vacuum
After Nov 15, 1993	25 mm Hg absolute (29 inches Hg vacuum)

Vapor vs. Liquid Recovery: Methods and Best Practices

Refrigerant can be recovered as vapor, as liquid, or using a combination of both methods. Understanding when to use each method significantly impacts recovery speed and efficiency.

Vapor Recovery Method

Liquid Recovery Method

Push-Pull Recovery Method

Best Practice: Combined Recovery Approach

For maximum efficiency, most technicians use a combined approach:

1. Start with Liquid Recovery: Remove bulk of refrigerant quickly as liquid (if system has 15+ lbs)
2. Monitor Pressure: When liquid line pressure equalizes with vapor pressure, liquid is depleted
3. Switch to Vapor Recovery: Complete the recovery and pull system into required vacuum
4. Wait and Verify: Wait 5-10 minutes after reaching vacuum to ensure no trapped liquid is vaporizing
5. Check for Pressure Rise: If pressure increases, continue vapor recovery until stable

Techniques to Speed Up Recovery

Recovery time directly impacts job profitability and customer satisfaction. Several proven techniques can significantly reduce recovery duration.

1. Cool the Recovery Cylinder

Most effective method for speeding recovery, especially with large refrigerant quantities.

• Place recovery cylinder in ice water bath
• Use wet towels on the cylinder (evaporative cooling)
• Position cylinder in shade or air-conditioned space
• Commercial refrigerant heat exchangers available for high-volume recovery

Why it works: Cooling the cylinder reduces internal pressure, maintaining a greater pressure differential between the system and cylinder, which accelerates refrigerant flow.

2. Heat the System (Carefully)

Increasing system temperature raises refrigerant pressure and speeds vapor recovery.

• Ensure adequate ventilation in the equipment room
• Use heat lamps or heating blankets on the evaporator
• Never use open flames near refrigerant
• Monitor system pressure - don't exceed safe operating limits
• Especially effective on low-pressure (chiller) systems

Caution: Excessive heating can cause refrigerant decomposition. Keep temperatures moderate and monitor continuously.

3. Use Short, Large-Diameter Hoses

• Standard hoses: ¼" ID (inside diameter)
• Better: ⅜" ID "charging" or "heavy duty" hoses
• Best: ½" ID hoses for large systems
• Keep hose length to minimum necessary
• Avoid coiled or kinked hoses that restrict flow

Impact: A ½" hose has 4 times the flow capacity of a ¼" hose. On large systems, this can cut recovery time by 50% or more.

4. Remove or Bypass Valve Cores

• Valve cores create significant flow restriction
• Use core removal tools or low-loss fittings with built-in core depressors
• Some modern systems have large-port service valves designed for faster recovery

Caution: Only remove cores if you have proper tools to control refrigerant release. Always use low-loss fittings required by EPA.

5. Start with Liquid Recovery

• Remove 80-90% of charge as liquid in a fraction of the time
• Use push-pull method on systems over 100 lbs
• Monitor with sight glass to know when to switch to vapor

6. Use Properly Sized Recovery Equipment

• Small residential recovery machine: 1-2 lbs/min vapor recovery rate
• Commercial recovery machine: 3-5 lbs/min vapor recovery rate
• Large industrial recovery machine: 10+ lbs/min with liquid capability
• Match equipment size to typical system sizes you service

7. Maintain Your Recovery Equipment

• Change oil regularly: Follow manufacturer intervals (typically every 5-10 recoveries)
• Replace filter-driers: Clogged filters drastically reduce recovery speed
• Clean condenser coils: Dirty coils reduce condensing efficiency
• Check for leaks: Recovery machine leaks waste time and refrigerant
• Purge air from hoses: Air in the system slows recovery

Recovery Equipment Certification Requirements

EPA requires that all refrigerant recovery and recycling equipment manufactured or imported after November 15, 1993, be tested and certified by an EPA-approved equipment testing organization.

EPA-Approved Testing Organizations

• Air-Conditioning, Heating, and Refrigeration Institute (AHRI) - Most common certifier
• Underwriters Laboratories (UL) - Also EPA-approved for equipment certification

Certification Requirements

Recovery equipment must meet standards specified in:

• AHRI Standard 740: Performance rating of recovery/recycling equipment
• Appendix B2, 40 CFR 82, Subpart F: EPA technical specifications
• Appendix C, 40 CFR 82, Subpart F: Standards for small appliance equipment

How to Identify Certified Equipment

Look for a certification label stating:

"This equipment has been certified by AHRI/UL to meet EPA's minimum requirements for recycling and/or recovery equipment intended for use with [appropriate category of appliance]."

Equipment Must Be Certified For Specific Refrigerants

• Recovery machines are tested and certified for specific refrigerant types
• Check the equipment label for approved refrigerants
• Using equipment with non-approved refrigerants voids EPA compliance
• Many modern machines are certified for multiple refrigerant classes

DOT Recovery Cylinder Requirements

The Department of Transportation (DOT) regulates refrigerant cylinder design, filling, and transportation.

Recovery Cylinder Identification

• Color Code: Yellow body with gray top (industry standard for recovery cylinders)
• DOT Markings: Must display DOT approval stamp (e.g., "DOT-4BA" or "DOT-39")
• Service Pressure Rating: Marked on cylinder (typically 400-800 psig depending on refrigerant)
• Tare Weight: Empty weight stamped on cylinder (critical for calculating fill weight)
• Test Date: Date of last hydrostatic test

The 80% Fill Rule

How to prevent overfilling:

• Use a digital scale to monitor cylinder weight during recovery
• Calculate maximum fill: (Cylinder tare weight + capacity) × 0.80
• Install mechanical float devices or electronic shutoffs (thermistors)
• Stop recovery before reaching 80% to allow for final vapor recovery

Cylinder Maintenance and Testing

• Hydrostatic Testing: Required every 5 years for DOT-4BA cylinders
• Test Date Location: Stamped on cylinder collar near the DOT marking
• Visual Inspection: Check for dents, corrosion, damaged valves before each use
• Valve Condition: Ensure both liquid and vapor valves operate smoothly
• Label Refrigerant Type: DOT requires cylinder contents to be clearly identified

Never Mix Refrigerants

• Use separate recovery cylinders for each refrigerant type
• Mixed refrigerants may be impossible to reclaim and must be destroyed (expensive)
• Label cylinders clearly with refrigerant type and date
• If unsure of cylinder contents, verify with pressure-temperature check before adding more refrigerant

Disposable vs. Recovery Cylinders

Special Recovery Procedures

Low-Pressure Chiller Recovery

Low-pressure systems require special techniques due to their vacuum operation:

• Remove liquid first: Pump liquid refrigerant to storage/recovery cylinder before vapor recovery
• Use water-cooled recovery machines: Most low-pressure machines connect to potable water supply
• Circulate chilled water: Keep chiller water pumps running during recovery to prevent tube freezing
• Nitrogen pressurization: May be used to aid liquid removal and leak detection
• Large vapor volume: A 350-ton chiller can retain approximately 100 lbs of vapor at 0 psig even after all liquid is removed
• Extended recovery time: Achieving 25 mm Hg absolute requires patience - may take several hours

System with Receiver/Storage Tank

• Pump-down refrigerant into receiver before recovery
• Close receiver service valve to isolate refrigerant
• Recover from receiver liquid port for fastest recovery
• Minimizes refrigerant-oil mixing

Recovery During Disposal

Special rules apply when recovering refrigerant from equipment being scrapped:

• Must still meet evacuation requirements - EPA eliminated the disposal exception
• Recordkeeping required: For systems 5-50 lbs, technicians must document date, location, refrigerant type, and quantity recovered
• Final disposer responsibility: Person disposing of appliance must ensure refrigerant recovery
• Small appliances: Recovery required even though they have simplified evacuation requirements

Recovery from Leaking Systems

EPA allows limited exceptions when evacuation to required levels is not possible due to leaks:

• Isolate leaking components from non-leaking components whenever possible
• Evacuate non-leaking portions to required EPA levels
• Evacuate leaking sections to lowest level attainable without substantially contaminating refrigerant
• Leaking sections must be evacuated to at least 0 psig
• Document the leak situation and recovery limitations

Common Recovery Mistakes to Avoid

1. Not Waiting After Recovery

After reaching required vacuum, wait 5-10 minutes and watch for pressure rise. Trapped liquid refrigerant in oil or low spots will vaporize, increasing pressure. If pressure rises, continue recovery.

2. Using Wrong Recovery Equipment

System-dependent (passive) recovery equipment that uses the appliance's own compressor cannot be used on systems containing more than 15 pounds of refrigerant or on systems with non-functioning compressors.

3. Overfilling Recovery Cylinders

Always use a scale. Overfilled cylinders are illegal, dangerous, and most recovery equipment will refuse to accept them for disposal or reclamation.

4. Mixing Refrigerant Types

Once mixed, refrigerants often cannot be separated or reclaimed. The entire cylinder contents may need expensive destruction at an EPA-approved facility.

5. Ignoring Oil Loss

Liquid recovery removes significant oil from the system. Check and add oil as necessary when recharging. Vapor recovery minimizes oil loss.

6. Using Contaminated Recovery Equipment

Change recovery machine oil and filter-driers regularly. Old oil and clogged filters contaminate recovered refrigerant and slow recovery dramatically.

Exam Tips: Recovery and Reclamation

Common Exam Question Patterns

• "What is the required evacuation level for a [type] system with [charge size] using recovery equipment manufactured [date]?"
• "What is the difference between recovery and reclamation?"
• "Can recovered refrigerant be returned to equipment owned by a different company?"
• "What is the fastest way to recover refrigerant from a large system?"
• "What minimizes oil loss during recovery?"
• "What organization certifies recovery equipment?"
• "What standard defines purity for reclaimed refrigerant?"

Conclusion: Recovery is a Core Competency

Refrigerant recovery and reclamation procedures form the foundation of EPA 608 compliance and responsible HVAC practice. Whether you're working on a home refrigerator, commercial rooftop unit, or industrial chiller, proper recovery protects the environment, ensures equipment reliability, and keeps you in legal compliance.

Key takeaways for technicians:

• Always recover refrigerant before opening any system - it's the law
• Use EPA-certified recovery equipment manufactured after November 15, 1993
• Know the required evacuation levels for your equipment type and age
• Combine liquid and vapor recovery for maximum efficiency
• Never overfill recovery cylinders above 80% capacity by weight
• Keep refrigerants separated - never mix different types
• Maintain your recovery equipment for optimal performance
• Reclamation to AHRI 700 is required before selling to a new owner

Understanding these procedures thoroughly will not only help you pass the EPA 608 exam but make you a more competent, efficient, and environmentally responsible HVAC professional.