Although R-410A does not significantly fractionate with a leak, it will fractionate if the refrigerant is removed from the refrigerant drum as vapor.
Inside of the refrigerant drum the two refrigerants in the blend may separate. If the vapor were drawn out of the bottle, there may be more of one refrigerant than the other.
To avoid the potential for fractionation during the charging process, the refrigerant drum must be positioned to deliver liquid refrigerant. This may
involve simply inverting the refrigerant drum so that all liquid leaves the bottle, or in some instances, the drum may have a dip tube to draw liquid out while in the upright position. Always refer to the refrigerant drum for details on position during charging.