sometimes I'll get home and find the wall unit on even though it's still in the 'off' position. I cannot remember if it's just the fan or both fan/compressor.....regardless... what's wrong?what are my options?is it a configuration issue or am I looking at replacing the power brd or driver brd? how much is it gonna co$t me to repair? I'm suspecting it's not worth repairing but I'll make that decision later on.