Hi fellow fordsters,
have a 2016 f150 XLT crew cab 4wd 2.7 eco boost.
My question is concerning heat/ac. I had the heat on yesterday on the way to work. All is fine. I leave work and I have no heat at all. I can switch between vent positions… defrost,center and foot. I have no clue how this would work one minute but not the next. I’ve had the truck about 5 years and this is the first time I’ve had this problem

 

Try a hvac reset and see if it helps just search google. If you have dual zone climate control, try them separately.
If you have a scanner that can retrieve live data try to get the ECT reading after the vehicle has been fully warmed up.
Go to underneath your glove box, then turn from cold to hot, can you hear any noise from the blend door actuator moving the blend door inside the heater box.
If you don't think the hot coolant is getting into the heater core you need to check all the hose, it can be a stuck closed heater control valve.
Check your coolant level, and check for leaks too.