Rinsing, cleaning and disinfecting dialysate preparation and supply apparatus

Dialysate preparation and supply apparatus having a water intake port, a concentrated dialysate solution intake connector, dialysate connectors for delivering fresh dialysate to and removing spent dialysate from a dialyzer, and system pumps for pumping liquids through hydraulic circuitry connected to said intake ports, said hydraulic circuitry including said dialysate connectors, said apparatus further comprising a cleaning and/or disinfecting system comprising

• a chemical intake port on an accessible exterior surface of said apparatus for connection to sources of different treatment liquids, one at a time,
• said port being connected to said hydraulic circuitry,
• means for regulating the flow of liquid from said chemical port into said hydraulic circuitry,
• means for providing a plurality of keyholes corresponding to said different treatment liquids in said exterior surface at different locations, each said keyhole being adapted to receive a corresponding key on a treatment liquid connector connected to a source of one said treatment liquid, each said keyhole being adapted to not receive any key corresponding to any other said treatment liquid,
• means associated with said keyholes for sending electrical signals indicating the presence of a said key in a corresponding said keyhole, and
• electrical control means for controlling said pumps and said means for regulating, to pump one of said different treatment liquids for a specific period of time and at a specific flowrate depending on which keyhole has a key in it.