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A/C Refrigerant Analyzer Function





Ford Motor Company has approved the Rotunda Deluxe A/C Refrigerant Analyzer (198-00003) for use on Ford and Lincoln-Mercury vehicles (Figure 1). The analyzer provides the technician with a quick and easy way to identify the type and percentage of refrigerant (R-134a, R-12, R-22, or flammable hydrocarbon). The analyzer can also provide the percentage of air in the A/C system and automatically purge air from the system.

The A/C Refrigerant Analyzer is designed to identify vapor gas samples taken directly from automotive air conditioning systems or refrigerant storage cylinders. Refrigerant vapor passes through the multiple sensor Non-Dispersive Infra-Red (NDIR) sensing unit. The microprocessor calculates each refrigerant type and purity percentage which is displayed on the analyzer's Liquid Crystal Display (LCD).

The analyzer identifies the purity percentage of R-134a, R-12, R-22, hydrocarbon; and air in the sample. If the purity percentage of the R-134a or R-12 is 98% or greater by weight, a green "PASS" Light Emitting Diode (LED) will light. If refrigerants R-134a or R-12 do not meet 98% purity levels, the red "FAIL" LED will light. Levels of R-22 and flammable hydrocarbons above 2% will light the red "FAIL" light. If a hydrocarbon is detected above 5%, both the "FAIL" light and "HYDROCARBON" light will illuminate and a horn will sound alerting the user of potential hazards.

The percent of air contained in the sample will be displayed if the R-134a or R-12 content is 98% or above. The analyzer eliminates the effect of air when determining the refrigerant sample content because air is not considered a contaminant although air can affect A/C system performance. Air will automatically be purged until a pure refrigerant with a less than 2% by weight air measurement is reached.