EPA 608 Recovery Equipment and Recovery Cylinders
Updated October 27, 2026
Recovery equipment and cylinders come up in Core and in every type section of the EPA 608 exam. Here’s what to know about recovering refrigerant safely and legally, followed by free practice questions.
Recovery equipment
| Type | How it works |
|---|---|
| Self-contained (active) recovery | Has its own compressor and pulls refrigerant out of the system |
| System-dependent (passive) recovery | Uses the appliance’s own compressor, or system pressure, to push refrigerant into a container. Allowed only for small appliances. |
- Recovery and recycling equipment made after November 15, 1993 must be certified by an EPA-approved equipment testing organization.
- Recovery removes refrigerant and stores it. Recycling cleans it on site for reuse. Reclaiming reprocesses it to new-product purity (AHRI 700), verified by lab analysis.
- When switching refrigerant types, purge or clean the recovery machine, so refrigerants don’t get mixed.
Recovery cylinders
- Recovery cylinders are gray with a yellow top (shoulder) and have both a liquid and a vapor valve.
- Never fill a recovery cylinder beyond 80% of its capacity by liquid volume.
- Recovery cylinders must be DOT-approved, and the standard cylinders (DOT 4BA and 4BW) must be requalified (hydrostatically tested) every 5 years. The test date is stamped on the cylinder.
- Disposable cylinders, used for new refrigerant, must never be refilled or used for recovery.
- Transport cylinders upright and secured, and follow DOT labeling and shipping rules.
- Use a separate recovery cylinder for each refrigerant. Mixed refrigerants often can’t be reclaimed.
Free practice questions
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What colors identify a refrigerant recovery cylinder?Answer: ARecovery cylinders are gray with a yellow top. They're refillable and have both liquid and vapor valves.
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How often must a standard DOT 4BA or 4BW recovery cylinder be requalified (hydrostatically tested)?Answer: CThe standard requalification interval for DOT 4BA and 4BW cylinders is 5 years, and the test date is stamped on the cylinder.
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Which recovery method uses the appliance's own compressor?Answer: BSystem-dependent (passive) recovery relies on the appliance's compressor or system pressure. It's allowed only for small appliances.
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Can a disposable cylinder be used to recover refrigerant?Answer: DDisposable cylinders are for new refrigerant only. They must never be refilled or used for recovery.
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What must happen before a recovery machine used on R-22 is used to recover R-410A?Answer: BPurge or clean the recovery equipment following the manufacturer's instructions when changing refrigerants, so the refrigerants don't mix.
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Recovery equipment made after November 15, 1993 must be:Answer: ARecovery and recycling equipment made after November 15, 1993 must be certified by an EPA-approved testing organization.
Related: EPA 608 Core practice test and required evacuation levels.
Pass the EPA 608 exam on your first try
- All 168 questions across Core, Type I, Type II and Type III
- An explanation for every answer, with the rule or principle behind it
- Unlimited practice exams per section, scored like the real test (18 of 25 to pass)