Ac problems

I have 2007 pt cruiser standard model and the ac is fine for the first 1 - 1 1/2 hours then cooling slows, but not fan speed, also exposed lines under hood become frosted. I can turn the car off for 5-10 minutes and everything is back to normal for another 1 1 1/2 hours. What do you suspect is the problem

Perhaps the evaporator is freezing. The evaporator is the part within the HVAC system that incoming air passes through to be cooled.

If the evaporator freezes the airflow will be reduced or stop altogether until the evaporator defrosts.

I suggest you consult a shop that specializes in automotive AC systems. They have the equipment and expertise to correctly diagnose and repair your car’s AC.