My Amana Hi Effiency 12 central air unit does not turn on all the time, like today. We set the temperature at 75 degrees and the compressor does not seem to turn on. We had a man out to look at it, he said it was fine because it turned on. For the past couple of days, it has been on and will then shut off by itself. Today though, it hasn't worked at all. It is 95 degrees out right now and we are so hot, any ideas/help would be greatly appreciated. Thank you!