Why is my AC cold then warm?

Cools for a few minutes, then goes warm, then cycles back — that's classic evaporator icing. When the system is low on refrigerant (or the expansion valve is misbehaving), the evaporator coil temperature drops below 32°F and cabin humidity freezes on it, blocking airflow. Turn the AC off for 10–15 minutes; if it works fine again for a few minutes, you've confirmed icing. The real fix is finding the refrigerant leak or replacing the expansion valve — not another recharge.

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