My 2014 F150 had the same issue. I was able to solve the issue today.
To cut a long tale short, never use one of those do-it-yourself Freon cans from the parts store to add Freon.
I did it and let moisture into my system, as well as somewhat overfilling it.
It turns out that the computer in your Ford detects this and, as a safety measure, activates your high-speed fan.
I took it to a shop that properly emptied the Freon, vacuumed out the moisture, and then refilled to the proper amount.
I’ve seen this on a couple other message boards. We’d tried everything that came to mind. Nothing seemed to work, so I replaced the water pump, flushed the coolant system, and had it serviced.
I also replaced the ac sensor that one of the guys said worked for him. Another issue arose, and the advised solution was to replace fuse #27 beneath the hood.
Fuse #27 was burned on one end but not broken when I pulled it out. Even with the warmer weather the past three days, I replaced it and haven’t heard the loud jet engine fan noise in two weeks. Best of luck!
Even on cold days, I had the same issue with the fan running continually. To diagnose the problem, I had a very good technician that I work with install his computer on my truck.
It stated that my air conditioning line was producing 496 pounds of pressure. He claims the problem is with my air pressure sensor.
The fan switched off when we unplugged it. I’ll get the part the next day. I couldn’t find it at any of the auto parts stores, so I had to go to the Ford dealership.
It costs around $30.00. I’m hoping this will fix the problem I’m having with my 2014 F-150 5.0L.
It’s a simple repair. Remove the wire from the socket, unscrew the valve, and reinstall it.