Honda Repair: pressure switch on a 93 Honda accord lx, compressor clutch, honda accord

Question
I have a honda accord lx. The proble is the air conditioner the air sometimes blows cold and the turns hot. I took it to have the system charged and the tec told me that it was full. The compresser kicks on and the air is cold for about ten seconds and kicks off. There is no leak in the hoses because I had the system charged about a year ago and it is still full.  When it is not very hot outside the air is cool. What could be the problem.  

Answer
Does the system stay on?  Check to see if the fans are both running when the system goes warm.  Also look down and see if the compressor is still engaged.  The relay for the compressor is located directly behind the p/s reservour on the left fender.   Also the compressor clutch could be going bad.  

Craig