About once every two weeks, my AC is slow to begin cooling. The fan blows hot air for maybe 20 seconds, then the cool air appears and cooling is consistent. It did this last summer as well. I never know when the problem will occur.

Do I have a clutch problem, an electrical problem, or low coolant? Or something else?

The vehicle is. 2016 Explorer, 3.5L EcoBoost.

Probably no help but my brother had similiar symptoms on his rav 4. Also, later on the air wouldnt cool much on a very hot day. Checked all the things you discussed and couldn't resolve the issue. Fought it for probably a year until a month or so his alternator went out and the air issue was resolved with a new alternator. I still have no idea on the how or why and id say its was an anomaly for that to be your issue but your problem sounded so familiar, I thought id throw that out there.

I am going to check the tension on my serpentine belt. Maybe it is a little slack.

A few months ago, we had the bearings on the air conditioning compressor go out on a Ford Ranger. Railroad tracks and other bumps effected whether it worked or not. It took about 30 minutes to put a new one in and charge it.

Keith

Its probably your blend door moving slow in the hvac. Imagine all your air going through the heater core (hot) or the evaporator (cold) depending on the position of the door.

The blend door is probably sticking or the actuator is going out... Its been awhile but I'm having trouble thinking what else would come and go like that?

20 seconds? Check the blend door.

great idea. Since its intermittent, it might be difficult to confirm with a quick check. If so, just get it in the cold position then unplug the wire to the actuator. If the problem goes away for several weeks, you've got your confirmation. Then replace the actuator before you need heat.

I was thinking this weekend and your control head module cycles your doors on startup FYI. You may turn the car on and it cycles through everything making sure things are moving back and forth. All cars are prob diff. Maybe your car is doing that on purpose when you notice it FYI.

as mentioned possibly blend door

also watch the compressor as you have someone else start the car and see if the compressor clutch starts right away or after a litlle time.

it could be low on refrigerant they sell it in cans for not a lot , if the compressor is kicking in and you leave the blend door set to cold all the time it is worth trying a can of the refrigerant