_:vb50770520 . . "Fan moving return air -- air that is circulated from the building back into the HVAC system"@en . _:vb50770519 _:vb50767740 . . _:vb50767965 . _:vb50767579 . _:vb50767965 . _:vb50767579 . _:vb50767740 . _:vb50767579 . _:vb50770520 _:vb50767965 . _:vb50770517 _:vb50767579 . . _:vb50767740 . _:vb50767740 . _:vb50767965 . _:vb50770518 . . _:vb50767740 . _:vb50770518 _:vb50770517 . "Return Fan" . _:vb50767965 . _:vb50767579 . _:vb50770517 _:vb50770519 . . _:vb50770519 _:vb50770520 . .