R12 to R134a Conversions and Factory R134a Systems
(For Use With R12 and R134a Refrigerants Only)
For specific application information, contact your Smart VOV distributor.
Note: Both standard duty and severe duty Smart VOVs are available for all vehicles. The severe duty Smart VOV is recommended for areas where the temperature normally exceeds 105°F, e.g., Phoenix, Arizona, and is identified by a red mark on the white filter end (see illustration below).
2. The Smart VOV is supplied with four tabs on the white filter ( see illustrations ). Remove the Smart VOV filter tabs to match the filter tab configuration of the removed orifice tube. Also verify that the black tip configuration matches that of the removed orifice tube; this will be either a Across stop@ as shown in illustration 3, or a non-cross stop as shown in illustrations 1 and 2.
Note: if it appears that the tube ID is too small for the VOV to insert easily, replace the VOV O-rings with factory GM O-rings, which have a slightly smaller OD.
**ALL AIR AND MOISTURE MUST BE REMOVED FROM THE SYSTEM.**
( R134a charge = 90% of the manufacturer recommended R12 charge )
Adapter length may be reduced to accommodate bend requirements; always maintain at least 0.25 inches between the external thermistor and the pointed end of the VOV.
False tripping of the "loss of refrigerant charge switch" will occur without the Adapter.