Additional Information.Purge properly set to 3 min, 3 sec. and now working properly.Charging 3300psi, 80cf scuba tank:Charge set to 3200 psiTank and Omega pressure equalized at 2200psi per Omega gaugeAfter 30 min pressure only increased to 2600 and did not seem to want to increase.Observed that in addition to the normal "washing machine" noise from the Omega a consistant click or soft clank was heard at what seemed to be compressor rotation (less than 1 sec)Every time it happens the gauge needle jumps. This occurred at initial compressor start up.Help please!Ron