On a new installation the line set is brazed to a factory charged outdoor unit and an indoor coil shipped under a nitrogen holding charge, with the outdoor unit's service valves still closed. What does the recovery requirement call for before that brazing?
- ARecovery of the outdoor unit's factory charge before any joint is made
The factory charge stays sealed behind closed service valves during installation. It is not in the tubing being brazed and does not have to be removed.
- Nothing to recover, because no refrigerant is present in the sections being joined
- CRecovery of the nitrogen holding charge into a certified recovery cylinder
Nitrogen is not a refrigerant and is not subject to the recovery rules. A holding charge of nitrogen alone may be released.
- DRecovery is required only if the outdoor unit holds more than five pounds
Charge size does not create a recovery obligation where no refrigerant is present in the section being opened. The five pound figure belongs to a different rule.
Why B is correct
Nothing being cut or heated contains refrigerant. The factory charge is isolated behind closed service valves in the outdoor unit, and the indoor coil and line set hold nitrogen. The recovery obligation attaches to refrigerant that is present where the appliance is being opened, so a new installation of this kind has nothing to recover before brazing.
What this question is testing
This tests the trigger for the recovery requirement rather than the requirement itself. Candidates who treat recovery as something that happens on every job cannot explain why a new installation is different, and the difference is simply whether refrigerant is present.
On the job
New construction and change-out work runs on this sequence, and the risk is the day the technician forgets which side the valves are on. Opening the service valves before the line set is brazed dumps the factory charge into an open pipe, which is a release and an expensive one. Checking that both valves are front seated and capped before the torch comes out is the habit that prevents it.
Memory technique
No refrigerant in the pipe, no recovery in the plan. But check those valves twice.
Exam tip
Ask where the refrigerant actually is. Recovery attaches to the section being opened, not to the job as a whole.
Where to look it up
Refrigerant must be removed from an appliance before it is opened; a section that holds only nitrogen has nothing to recover.