Often confused · Small-appliance recovery
System-dependent vs self-contained recovery equipment
System-dependent recovery equipment captures refrigerant with the help of the appliance's own compressor or the pressure already in the system, while self-contained equipment brings its own compressor; the rule bars system-dependent equipment from appliances holding more than 15 lb of refrigerant unless it's permanently attached as a pump-out unit (40 CFR 82.156, eCFR as of October 5, 2026).
Part of Small-appliance recovery in the Study guide
Same 20-lb appliance, two setups
An appliance holding 20 lb of refrigerant needs its charge recovered. Setup one is a portable passive device, clipped on for the afternoon and relying on the appliance to push the refrigerant out. The rule bars it, because the appliance is over 15 lb. Setup two is a pump-out unit the owner had permanently attached to that same appliance. That's the rule's one exception, so the size limit doesn't apply to it.
Either way, a 20-lb appliance isn't a small appliance, so the technician needs Type II, Type III or Universal for its pressure class. The equipment rule and the certification rule look like one decision on a ticket. They're two, and the exam tests them separately.
A third requirement sits under both. Whichever kind of machine you carry, the Core test topics expect recovery equipment to be certified by a third party, a Core subject of its own (EPA test topics, checked October 7, 2026). On Type I, both kinds have to reach the 80/90% recovery requirement.
Passive and active, side by side
System-dependent vs self-contained recovery equipment under Section 608
| Item | System-dependent (passive) | Self-contained (active) |
|---|---|---|
| What moves the refrigerant | The appliance's own compressor, or the pressure already in the system | The recovery machine's own compressor |
| Appliance size limit | 15 lb or less, unless permanently attached to the appliance as a pump-out unit | No size cap in the rule |
| Where the exam asks about it | Core and Type I; the 15-lb cap also appears in Type II | Core, Type I, II and III |
| Counts as recovery | Yes: refrigerant is removed and stored, not processed | Yes, same definition |
Yellow edge: the two columns say different things on this row.
Sources: 40 CFR 82.152 and 40 CFR 82.156, eCFR as of October 5, 2026; EPA test topics (Core, Type I, Type II), checked October 7, 2026.
Same equipment, different names
- System-dependent
- Also called passive or appliance-dependent. Relies on the appliance's compressor or internal pressure.
- Self-contained
- Also called active or system-independent. Brings its own compressor to the job.
- Pump-out unit
- Recovery equipment permanently attached to an appliance; the one case where system-dependent equipment may serve an appliance above 15 lb.
- Recovery
- Removing refrigerant and storing it, with no processing. Cleaning it is recycling; bringing it to AHRI 700 purity is reclaiming, both on recover, recycle, reclaim.
Passive or active: make the call
Note the appliance's charge and what's meant to move the refrigerant before you pick.
0 right · 0 of 6 answered
System-dependent recovery devices may be used only on appliances holding a maximum of how many pounds of refrigerant?
Why each option is right or wrong
Answer: A. 15 pounds of refrigerant or less.
- ACorrect: system-dependent recovery equipment may be used only on appliances holding 15 lb of refrigerant or less.
- BWrong: 12 lb isn't the limit; the cutoff is 15 lb.
- CWrong: appliances above 15 lb need self-contained recovery equipment.
- DWrong: 10 lb isn't the limit; the cutoff is 15 lb.
System-dependent recovery equipment may be used only on appliances holding 15 pounds of refrigerant or less, whatever the refrigerant. Larger systems need self-contained recovery equipment.
What is the primary function of active recovery equipment used in HVAC systems?
Why each option is right or wrong
Answer: C. Removes refrigerant using an external recovery machine.
- AWrong: needing the appliance compressor describes system-dependent recovery, not active recovery.
- BWrong: capturing into non-pressurized containers like bags is a passive method.
- CCorrect: active (self-contained) equipment uses its own compressor to pull refrigerant out of the appliance.
- DWrong: active equipment doesn't rely on atmospheric pressure; it has its own pump.
Active recovery involves using a recovery machine to extract refrigerant, unlike system-dependent methods that rely on the appliance's compressor. It is effective for removing refrigerants quickly and efficiently.
What is a key advantage of using a system-independent (active) recovery device for small appliances?
Why each option is right or wrong
Answer: C. It can recover refrigerant even if the appliance's compressor is not working
- AWrong: recovery machines don't sort refrigerants; you must keep different refrigerants separate yourself.
- BWrong: an active machine uses its own power, so it doesn't save electricity.
- CCorrect: because it has its own compressor, an active machine can recover refrigerant even when the appliance compressor doesn't work.
- DWrong: the type of equipment doesn't reduce documentation requirements.
System-independent recovery devices have their own compressors or pumps, allowing them to recover refrigerant from systems with non-operational compressors. This is particularly important for handling equipment that has failed or is being disposed of.
Under the Section 608 rules, in which case is an appliance-dependent recovery method not allowed?
Why each option is right or wrong
Answer: D. A commercial refrigeration appliance containing 18 pounds of R-404A
- AWrong: a 4 lb PTAC is well under 15 lb, so system-dependent recovery is allowed.
- BWrong: 10 lb is under the 15 lb limit, so system-dependent recovery is allowed.
- CWrong: 14 lb is under the 15 lb limit for system-dependent recovery.
- DCorrect: system-dependent recovery isn't allowed on appliances with more than 15 lb of refrigerant, and 18 lb is over that limit.
System-dependent recovery is allowed only on appliances holding 15 pounds of refrigerant or less, so an 18-pound commercial system needs self-contained equipment.
Which sequence of actions is required when utilizing an appliance-dependent recovery method to safely capture refrigerant from a functional small appliance?
Why each option is right or wrong
Answer: D. Connect bags, run the compressor
- AWrong: venting the vapor is prohibited.
- BWrong: cutting the lines releases refrigerant instead of capturing it.
- CWrong: passive recovery uses the appliance's own compressor; flushing lines would release refrigerant, not capture it.
- DCorrect: attach a recovery bag or container and run the appliance's compressor to push refrigerant into it.
Appliance-dependent recovery relies on the system's own compressor to pump refrigerant into a capture container. Lines must never be severed or vented during this process.
A technician must use a system-dependent recovery device on a small appliance whose compressor will not run. What should the technician do to recover the refrigerant properly?
Why each option is right or wrong
Answer: D. Access both high and low sides and warm or tap the compressor
- ANitrogen dilutes the charge in the bag and does not replace proper two-side access.
- BWith one access point and no compressor, much of the refrigerant stays trapped in the system.
- CThe compressor is inoperative, so forcing it on will not move refrigerant and risks damage.
- DCorrect: with the compressor dead, access both sides and heat or tap the compressor to free refrigerant.
When the appliance compressor does not run, system-dependent recovery needs access valves on both the high and low sides. Warming and tapping the compressor helps release refrigerant trapped in the oil.
More practice across all four sections: Practice test · Timed mock
Common follow-ups
Does the system-dependent limit matter for small appliances?
Not in practice. The cap applies to appliances holding more than 15 lb (40 CFR 82.156, eCFR as of October 5, 2026), and a small appliance holds five pounds or less by definition. On a small appliance the number that matters is the 80/90% recovery requirement.
Where does the recovered refrigerant go afterward?
Into a recovery container; the recovery cylinders page covers the gray-and-yellow DOT cylinders. It may go back into the same appliance or another one owned by the same owner without recycling or reclaiming, but it can be sold to a new owner only after a certified reclaimer brings it to AHRI 700 purity (40 CFR 82.154 and 82.156, eCFR as of October 5, 2026).
Are “active” and “system-independent” the same thing?
Yes. Self-contained, active and system-independent all describe a recovery machine with its own compressor. Passive, system-dependent and appliance-dependent all describe the reverse. The exam rotates the names.