Partway through a recovery job a technician discovers the cylinder in use already contains refrigerant of a different type from an earlier job. What is the consequence of that mixed cylinder?
- The mixture cannot be reclaimed and normally has to be sent out for destruction at the owner's expense
- BThe mixture can be reclaimed as long as both refrigerants in it were HCFCs recovered that day
Sharing a chemical family does not make two refrigerants separable. Reclaimers reject a mixed cylinder whatever it holds and whenever the second refrigerant went in, because separation is not a process they run.
- CThe mixture can be recycled on site and returned to either system it came from once it is filtered
Recycling equipment removes oil, moisture, and acid. Passing a mixture through a filter-drier does not pull one refrigerant out of another, so filtering does not rescue a mixed cylinder.
- DThe mixture is acceptable as long as the cylinder is kept below eighty percent full, which is the only limit that applies
The fill limit is a pressure safety rule for the cylinder and says nothing about what is inside it. A correctly filled cylinder holding two refrigerants is still a disposal item.
Why A is correct
Separating a blend of different refrigerants is not practical at a reclamation facility, so once refrigerants are mixed in a cylinder the batch is off the table for reclamation. The remaining route is destruction, which the owner pays for by weight. That expense is why dedicated, clearly tagged recovery cylinders are standard practice.
What this question is testing
This is an applied consequences item. It tests that you know reclamation cannot separate refrigerants, that recycling cannot either, and that the fill limit is an unrelated rule, which requires holding three separate concepts straight. Only one of the four choices describes an outcome that actually happens in practice.
On the job
Every shop that has been around a while has a mixed cylinder in the corner that nobody wants to pay to get rid of. It usually happens exactly as described, a partly used cylinder grabbed off the truck in a hurry with no tag on it. The fix costs nothing: label the cylinder the moment the first refrigerant goes in, and keep a separate cylinder for each refrigerant you commonly handle. Charging a customer for destruction of refrigerant you mixed is a conversation worth avoiding.
Memory technique
40 CFR Part 82, Subpart F
Exam tip
Mixed refrigerants cannot be reclaimed and end up destroyed at cost. One refrigerant per cylinder, always tagged.
Where to look it up
Mix it and you buy it. A tagged cylinder is cheaper than a destruction invoice.