Recovery is a trade with a rule bolted to it, and the two are easy to confuse. The rule decides what must be removed, how completely, with what equipment and who may do it; the trade decides how you actually get there — which valve to close, which gauge to trust, where the liquid is hiding. This guide reads the regulations directly and is explicit about the boundary: where the rule specifies something it says so and quotes it, and where the answer is craft it says that instead of dressing an opinion up as a citation. Orientation for study, not a substitute for the refrigerant's own safety data sheet, the equipment manual or an employer procedure, and not affiliated with any agency or exam body.
Each chapter opens with the short version. Tap one to read the detail.
Recover, recycle, reclaim — three words the rule defines apart
~2 min
The whole subject hangs on one prohibition and three verbs. Nobody servicing or disposing of an appliance may knowingly vent refrigerant; recovery removes it, recycling cleans it for the same owner, and reclaiming reprocesses it to a published specification. Only the third makes it fit to sell on.
Small appliances: a percentage, not a vacuum
~2 min
Small appliances are the one family where the rule states recovery as a fraction of the charge rather than as a vacuum level, and the fraction depends on how old the recovery machine is. Disposal of a small appliance needs no certification at all.
High-pressure work: evacuate to a table, with certified equipment
~2 min
For everything except small appliances and vehicle systems, the rule requires evacuation to levels set out in a table, using a machine certified under its own section — and the required level depends on the appliance's charge size and on whether the machine is new or old.
Low pressure: the machines that can pull themselves into a vacuum
~2 min
Low-pressure appliances run below atmospheric pressure in normal operation, which changes everything about recovery: air leaks in rather than refrigerant leaking out, and the rule restricts how such a system may be pressurised at all.
The cycle, and the two ways a rule measures a charge
~2 min
No federal document teaches the refrigeration cycle as a trade. What one does specify is how a correct charge is verified — by superheat on a fixed-orifice system and by subcooling on one with an expansion valve — and that single distinction carries most of what a recovery technician needs from the cycle.
What the rule measures, and what it leaves to you
~2 min
A regulation specifies exactly as much instrumentation as it needs to be enforceable — a vacuum expressed in two units, a balance's sensitivity, an annual calibration — and no more. The manifold, the chart and the probe are the technician's craft.
Contamination is defined by what has to be removed
~2 min
The rule names the contaminants by naming the device that removes them — moisture, acidity and particulate — and sets air and water as specified limits in the purity standard. The oil is a separate regulatory world with its own rule.
Evacuation, charging, and the equipment that has to be certified
~2 min
The service sequence is bounded at both ends by the rule: recovery equipment must be certified against a standard, and evacuation must reach a stated level with the liquid included. What happens between those points — how you pull a vacuum efficiently — is technique.
Once it is in a cylinder, it is the transport rules' problem
~2 min
A filled recovery cylinder is a shipped hazardous material, and the fill limit is a ratio of weights rather than of volume. A cylinder overdue for periodic requalification may not be filled and offered for transport at all.
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