flow up the annulus formed around the single tube and the production casing or production tubing fluid is pumped down the conduit 205 and through connector 210 to fill the single fluid conductor 220 and line 215 egress check valve 295 prevents fluid from entering the pumping piston from the tube as fluid continues to pump down the tube and through single fluid conductor 220 into the upper driving piston chamber 222 the driving piston head 225 moves downward pushing the pumping piston head 270 downward as the pumping piston head 270 moves downward fluid from the well enters the pumping chamber 262 through ingress check valve 255 and ingress port 260 this continues until the force being exerted by the fluid pressure on the driving piston head 225 is equal the force being exerted by the resilient chamber 280 on the pumping piston head 270 at this point additional fluid being pumped by the conduit 205 has no further effect unless the pressure is increased once the pumping chamber is filled or at least partially filled the pressure on the conduit 205 can be released by a controller on the surface at this point the resilient chamber is exerting a much greater force on the pumping piston head 270 than being exerted on the driving piston head 225 the ingress check valve 255 prevents fluid from exiting the pumping chamber 262 via the ingress port 260 the only.