I noticed my Ford Ranger was only blowing hot air when set to bring in outside air, regardless of the temperature outside or what my climate control is set to. I noticed (by accident) that if I turn on my AC to Max AC, that cycles air from inside the car, I can get some cold air moving through the vents. However regular AC, that pulls air from outside, still comes out like a sauna. I checked the refrigerant and fuses, but both are fine. I thought maybe it could be the compressor, but would the AC work at all if the compressor was dead?
It sounds to me like the blend door actuator is stuck or not cycling properly. The recirc flap may force it to move through the A/C coils. If you can hear the A/C compressor cycle as you'd expect (conversely, if you can see condensation on the refrigerant line going into the cab), this seems like a likely scenario.
You can also just feel the line if you don't see any condensation. I don't know where you're at in the world, so if your humidity is really low, you might not see condensation ... but it would still be cold going into the engine compartment. Make sure you feel both lines (in/out). One should be cold (after it's been running a bit) and the other should be warm if refrigerant is moving as it should.