(under subclass 199.1) Apparatus in which one of the pumps is priming or maintaining the other pump primed and including means responsive to the level of pump fluid in some part of the system to control the pump fluid or modify the operation of at least one of the pumps.
(1) Note. The operation of the pump is considered to be modified, for example, if the drive means is controlled, the capacity is varied, or a valve is operated to bypass the discharge, to draw from a different source, to deliver to a different place or vary the inlet or outlet.
