Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Refrigerant Identification / Testing




Special Tools


1. Use the A/C refrigerant analyzer to identify the refrigerant type and purity. Refer to the manufacturer's operating instructions.
^ If the purity percentage of the R-134a or R-12 is 98% or greater by weight, a green PASS LED will light. Proceed with the refrigerant recovery.
^ If the R-134a or R-12 does not meet 98% purity, a red FAIL LED will light. Proceed with the refrigerant recovery.
^ Levels of R-22 and flammable hydrocarbons above 2% will light the red FAIL LED. Refer to Recovery of Contaminated A/C Systems in this section.
^ If a flammable hydrocarbon is detected above 5%, both the FAIL and HYDROCARBON LED's will light and a horn will sound.