Performed PSA maintenance. Tech found compressor not shifting from first to second stage properly. Blower control board (not defrost board) is wired to compressor solenoid. Board is sending 12 volts AC and 22 volts DC to compressor solenoid all the time regardless of whether or not Y2 is calling. Did see compressor shift to high stage once, but not consistently. Tech recommends replacing blower control board. Please order board. Extended Premium maintenance.