Having (after commenting on not to have a you're wrong I'm right match on here) taken the time to read through the AMM for my own reassurance of system knowledge and for the benefit of ALL readers here not having access to this document, the following extracts, make of them what you want:
AIR CONDITIONING - DISTRIBUTION - INTRODUCTION
Recirculation System
The recirculation system permits ventilation of air in the passenger cabin areas. The recirculation system decreases the use of engine bleed air. This enables better thrust management and decreases fuel consumption.
AIR CONDITIONING - DISTRIBUTION - GENERAL DESCRIPTION
Recirculation System
The recirculation system uses two fans to move air from the passenger compartment to the mix manifold. This system reduces the amount of air that the packs need to supply.
AIR CONDITIONING - RECIRCULATION SYSTEM - INTRODUCTION
Purpose
The recirculation system supplies air for ventilation. The use of cabin air for ventilation decreases the use of air from the engine bleed system.
General Description
The recirculation system collects cabin air to use with pack air in the distribution system. The distribution system supplies air to the passenger compartment area.
Operation
The recirculation fans are enabled when you move the RECIRC FAN switches to the AUTO position. Recirculation fan operation depends on air conditioning pack operation.
AIR CONDITIONING - RECIRCULATION SYSTEM - RECIRCULATION FAN
Functional Description
The recirculation fans pull air in from the passenger cabin and supply it into the main distribution manifold.
The right recirculation fan pulls in air from the collector shroud in the forward cargo compartment.
Floor grilles in the passenger compartment permit airflow into the collector shroud.
The left recirculation fan pulls in air from the distribution compartment.