Burnout Recovery and the Relabeled Cylinder
You are the lead tech at a two-van shop. A 12-year-old, 3-ton R-410A split has just been condemned after a grounded compressor; the oil is black and smells acidic. Your helper recovered the charge into a 30-lb recovery cylinder with a water capacity of 47.6 lb and a tare weight of 22 lb. That cylinder was last used two years ago and still wears a hand-written "R-22" label; it was emptied and triple-evacuated before this job. The system nameplate reads 9.5 lb and the cylinder now gross-weighs 51 lb. The owner of the shop wants the recovered gas put into the next R-410A system you install, saying, "It's a blend - it's still good refrigerant."
1. May the recovered charge be installed into another customer's system? Justify your answer with what a reclaim standard actually requires.
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No. Recovered refrigerant out of a burnout is the worst-case feedstock there is.
- A burnout generates acids, sludge, copper plating and particulate. Those contaminants are in the gas you recovered, and they will migrate to the new system's TXV, filter drier and compressor windings.
- Refrigerant may only be returned to service in another owner's equipment if it has been reclaimed to AHRI 700 - meaning tested for moisture, acidity, high-boiling residue, chloride and particulates, and certified by an EPA-certified reclaimer. A shop cannot self-certify that.
- Mixing recoveries from multiple systems, or from a burnout, into one cylinder makes the contents unreclaimable as a named product. Most reclaimers will take it only as "burnout/dirty" and may destroy it by incineration.
Correct action: label the cylinder for what it is (R-410A, burned-out/dirty), keep it segregated from clean recoveries, and ship it to a certified reclaimer. If you must pump a burnout again, run a dedicated filter-drier on the recovery machine's discharge and use hoses you can dedicate to dirty work.
2. Evaluate the cylinder itself: the label, and the 51-lb gross weight. Would you fill it further?
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Two separate problems.
Labeling. A cylinder must be marked for the refrigerant it actually contains; a cylinder carrying an "R-22" marking cannot be filled with R-410A. Remove the old label and apply a permanent R-410A label before the fill. A properly evacuated cylinder can be repurposed, but the marking has to follow the contents - mislabeled cylinders are how cross-contamination enters the recycle stream.
Weight. Net contents are 51 − 22 = 29 lb. The common working limit is 80% of water capacity: 0.80 × 47.6 = 38.1 lb, so 29 lb is under the 80% mark. But the 80% rule is only a proxy for liquid expansion - always confirm the fill limit stamped by the cylinder manufacturer, charge on a scale, and never exceed the marked gross weight.
Do not top this cylinder off from a second job, and never use a torch or hot water to raise pressure; warm the cylinder only in a controlled way and watch the scale and the pressure.
3. The nameplate says 9.5 lb and only 6.2 lb came out. What is the significance, and what should have happened?
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About 3.3 lb of refrigerant is still in the circuit, and it will be released to atmosphere the moment someone cuts the lines - a violation of the venting prohibition and a handling failure.
Why recovery stalls:
- Vapor recovery slows as the system pressure falls toward the cylinder's own pressure. The last pound comes out slowly.
- Charge can be trapped behind a closed liquid-line solenoid, a check valve, or in a second circuit the helper didn't know about.
- A hot recovery cylinder (truck bed, direct sun) can't accept much vapor.
What should happen:
- Pull from high and low sides, with any solenoids energized open.
- Keep the cylinder cool and out of the sun; use a machine with a subcooler if available.
- Run until the system is at 0 psig - never into a vacuum unless you are also evacuating the circuit.
- Weigh the cylinder before and after and compare against the nameplate; an unexplained shortfall is an unfinished job, not a rounding error.