Robinair 16910 ID Plus Refrigerant Identifier - Manual (Page 18)

16
Operating Procedures
Time Out: To conserve refrigerant during a potentially long purging procedure, the
instrument automatically halts the operation after a time-out of 1-1/2 hours. You are
asked if the procedure is to continue. To restart the procedure, press the “A” button;
press the “B” button to end the session and return to calibration. Note that purge
duration in excess of 1-1/2 hours is unusual (assuming a 50 lb. cylinder or smaller
is being purged) and can be caused by high levels of air contamination, refrigerant
contamination other than R-12, R-134a, R-22, or hydrocarbons, or by absence of liquid
refrigerant in the refrigerant source.
Calibration: To keep the instrument at peak accuracy, an occasional self-calibration
is performed. The purge procedure is momentarily halted until completion of the
20-second self-calibration operation. The self-calibration automatically occurs after the
first five minutes of the purging procedure, and then at 10-minute intervals thereafter.
The calibration operation is fully automatic and requires no intervention.
Normal Purging Procedure: During the purging process, the instrument displays
NOW AIR IS XX.X% PURGING TO X.X%. Purge times vary with application and
are dependent upon headspace size in the source, amount of initial air contamination,
and the purge limit setting. Typically, it requires three minutes to purge an automotive
air conditioning system from 8% to 2% contamination levels. A typical 50 lb. storage
cylinder that is at least 50% liquid requires one hour to reduce the contamination levels
from 8% to 2 %. Observation of the instrument display reveals air contamination levels
may rise and fall during the purging procedure. This fluctuation is normal and is the
result of air coming out of liquid solution and repeated refrigerant displacements of air.
5. When the purging procedure is complete, the instrument display reads DONE, AIR
IS X.X% PRESS B TO EXIT and the green LED flashes. Press the “B” button to exit
the purge operation and return to the calibration operation to be ready for another
refrigerant identification procedure. Replace the cap on the purge port, and disconnect
the service end of the sample hose BEFORE calibration occurs. If the instrument will
not be used again at this time, unplug the power cord to power down the instrument.