is the clutch engaged/spinning on the compressor when the A/C is turned on inside the car? as far as it blowing out the defrost and floor.that means you most likely have a vacuum hose leak and the blower has defaulted to the defrost/floor mode like it should.find the vacuum leak and repair it,either under the hood close to the firewall or under the dash.
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Everything kicks on just feels like the heater is stuck on you can feel a tiny but of air but more heat comes out then air