Self-priming pump system

A system for priming a pump during startup and repriming a pump during operation, comprising:

• a pump having an inlet and an outlet, an impeller disposed between said inlet and said outlet, and an inducer disposed between said inlet and said impeller;
• said inlet, inducer, impeller and outlet defining a primary flow path through said pump;
• a liquid reservoir in communication with said pump through said inlet;
• a recirculation loop including a separate discharge priming reservoir outside of said primary flow path for storing priming liquid for said pump, said recirculation loop having an inlet conduit extending from said separate discharge priming reservoir and in communication with said pump at said outlet for delivering priming liquid from said pump to said separate discharge priming reservoir and said recirculation loop also including an outlet conduit extending from said separate discharge priming reservoir and in communication with said pump downstream of said inlet between the ends of said inducer for delivering priming liquid from said separate discharge priming reservoir directly to said pump, said recirculation loop including means outside of said primary flow path and associated with said separate discharge priming reservoir for separating air from priming liquid delivered from said pump;
• a priming valve disposed in said outlet conduit between said separate discharge priming reservoir and said pump, said priming valve being adapted to be opened at startup for priming said pump and during operation for repriming said pump by allowing priming liquid to flow freely through said inlet conduit for circulation from said separate discharge priming reservoir directly to said pump at said inducer, through said inducer and said impeller, and through said outlet of said pump back to said separate discharge priming reservoir, said inducer and impeller causing air in said inlet of said pump to be entrained in and pumped with said priming liquid for removal and venting of air from said separate discharge priming reservoir;
• and
• means for opening and closing said priming valve during operation of said pump, said opening and closing means being adapted to ensure said pump is always maintained in a fully primed condition.