The right recirc fan recirculates cabin air,the left recirculates air from the air conditionning bay.
Left is located back of fwd cargo,right fan on top of fwd cargo.
Fwd cargo is air tight,no air goes into it,or at least not supposed too...you wouldnt want a continous oxygen air source for it now would you?
The air that is going around the fwd cargo(for conductive heating)is air pulled by the exhaust fan,(cockpit air/eebay).
So recirc fans air is air recirculated air from Air con bay and cabin tonyhe mix manifold and then end their journey via the tube' ass ,the outflow valve that is.
Clear?