a/c compressor fuse blows

I have a 2015 t800 day cab and the fuse/breaker for the air conditioning compressor gets really hot and trips. The fuse will cool off and the a/c compressor will work again and cool the truck off. The fuse, and relays for everything have been replaced. I can switch out the fuse with another and it will work for another two hours or so. The heater does not work either. The electric valve that controls the coolant flow to the heater core works.
It have spent almost as much time at Kenworth of Houston (performance truck) as we have had it. It is not going back to them. 1200.00 later and it still does the same thing. They have admitted there is a problem, but cant find it. I'm on my own now, any help would be great.

I'm going to replace the a/c compressor clutch tomorrow.
If that doesn't work the hvac controls on the dash, then the coolant valve.

 

The 250k mile warranty is drivetrain only.

The blower works great. The flow control gates for the direction also work.

 

Warranty has exceeded the mileage

 

Not a bad idea. I was going just to replace the clutch on the compressor, not the whole unit. I think the clutch is $30-$40