Plan 02 would be better named as Plan 00 because there is no flush.  Seal generated heat is removed by convection and conduction to the process fluid, pump components, and the surrounding environment.  In general, Plan 02 is not recommended; however,  it is sometimes used in conjunction with API Plan 62 and/or the optional use of a cooling jacket, which may provide additional cooling. This plan should only be used for services where adequate vapor suppression can be assured, so that vaporization of the process in the seal chamber or at the seal interface does not occur.