Ac troubles

Have you tried cleaning the fins on the condenser and air to air cooler?

 

Check filters, turn on see if and when clutch turns check plug for compressor, reset it, belt and or tension pulley on and on

 

Sounds like possibly a blend door is getting stuck?

 

The door that allows airflow controlled by the actuator...

I had a similar problem that you are having with my peterbilt. The system had to be evacuated, then the entire hvac was removed in order to fix the broken blend doors...

 

U tube Cascadia ac reset

 

First thing to check is the fan operation at idle, with a/c on. Make sure it’s working. If so, chances are the front of the radiator is blocked with dirt and debris. Take condensor off, leaving the lines hooked up. Set it aside, and clean the radiator fins, along with the condenser fins. Use water and air, maybe some brake keen, from the backside first. Be careful not to use too much pressure and bend the fins. Normally when idling the fan pulls air in to cool the condenser, and lower the pressure. If the fins are corroded badly, you may need to use a tiny screwdriver to clean in between them, very time consuming. An inexpensive fin comb will come in handy.