I have a 1950's Cavalier 96. It has been working wonderfully since I got it. Now, there is a problem with ice forming on the cooling coils. I have turned it down but that does not seem to help. (I am not particularly well versed in this department) I have to shut it down, let the ice melt and then start it up again. This is a pain in the rear, to say the least. It does cool but never seems to shut off. The fan blades eventually come into contact with the ice build up on the coils. I don't think this is the original cooling system but as I said, until now, it has been just fine. All of this started this spring when we have high humidity. Never had a problem all winter. Can some one point me in the right direction. Do I need a new thermostat, a new on off switch? Does anyone have one or where can I get one?