Regarding your question, this may be because you set the circulation mode to external circulation before turning off the air conditioner, so that when the vehicle is driving, air enters the air duct through the air conditioner filter element and then enters the cab through the air conditioner outlet. It is suggested that you adjust the air conditioner to the internal circulation mode, and observe it in the trial operation after adjustment. If there is still warm air blowing out, it may be caused by the lax closing of the air door in the air duct. I suggest you follow the above analysis to check.