F250 Diesel A/C problem

I have a 2002 F250 7.3 diesel. My A/C blows cold for a few minutes and then start blowing hot air , I turn it off and let it set for 5 to 10 minutes and turn it back on get cool and just run for 10 minutes. I check the pressure, change low pressure sensor and cycling switch no luck can someone up there help me.
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If it's just "not cooled", check your clutch gap. Perform a shimectomy if needed.
If it's intermittently HOT, you've probably got a busted blend door flopping around.
Steve








