Hot air cannot cool something that's at a lower temperature. Convective heat transfer can only occur when the object and the air flowing around it are at different temperatures. And heat will always flow from the hot thing to the cold thing. It will never flow the other direction. Also you should use a thermocouple for this, it will be more accurate. Just gotta make sure you dont short out the pcb with the metal thermocouple tho.
KenKaniff- t1_j5pglb8 wrote
Reply to Why does hot air cool? by AspGuy25
Hot air cannot cool something that's at a lower temperature. Convective heat transfer can only occur when the object and the air flowing around it are at different temperatures. And heat will always flow from the hot thing to the cold thing. It will never flow the other direction. Also you should use a thermocouple for this, it will be more accurate. Just gotta make sure you dont short out the pcb with the metal thermocouple tho.