packer mounts to the pump assembly below an intake of the pump and is lowered in with the pump assembly the packer is radially expansible to seal against the casing in the well a conduit leads from the pump assembly to the packer for diverting a portion of the well fluid being pumped through the pump assembly this pressurized fluid causes the packer to expand and seal against casing application_number US 81706504 A description referring to fig1 well 11 has a casing 13 that is cemented in place perforations 15 in casing 13 admit well fluid into casing 13 a string of production tubing 17 is lowered into casing 13 tubing 17 may be made up of individual sections of pipe screwed together or it may comprise continuous coiled tubing an electrical submersible pump assembly 19 is suspended on the lower end of tubing 17 pump assembly 19 in this embodiment includes an upper pump 21 upper pump 21 is preferably a conventional centrifugal pump having a number of pump stages 23 shown schematically by the dotted lines each pump stage 23 comprises an impeller and a diffuser not shown alternately upper pump 21 could comprise a different type of pump such as a progressing cavity pump a lower pump 25 is mounted below upper pump 21 lower pump 25 is also conventional and has at least one stage 27 having an impeller and a diffuser upper pump 21 preferably has many more stages 23 than the stages 27 of lower pump 25.