sandman2000

I have a 2014 F-150 XLT 4x4 crew cab 3.5L eco boost. I really can't say anything bad about the truck, I haven't had ANY issues. Until... This past Friday, I went fishing a/c worked great. When I got back to load the boat I noticed my a/c only blowing hot air. I haven't heard any noise ( knocking/tapping) or had any warnings, that I know. I generally ride by myself about 600-700 miles a week. I've read a few discussions which mention warning sign such as, the passenger side blowing hot and driver side blowing cool until it doesn't.

Any words of advice would be greatly appreciated. TIA.

16IngotFX4

Lets first start out by deciding if you have an actual air conditioning question or if you have an HVAC question?

Are you turning on the actual air conditioning on and it is not working or is the temperature only blowing warm are regardless of what you ask the temperature to be.

I don't think you have auto climate in that truck do you?

Turbonut

Does the clutch engage when a/c on?
If not, first item I would check would be the pressures in the system.
Check with gauges, or, not the best way, tap one of the
Schrader valves to see if any pressure, but keep your eyes away from the
area and put safety glasses on if one wants protection.

Depending on the test results you'll know if there is a refrigerant loss, or
problem elsewhere.

raski

If the refridgerant level gets too low, the clutch will not engage as a safety measure. If the clutch is engaged, compressor running, the two lines running into the evaporator should be cold.Those are the lines running into the firewall.If they are cold, you have a blend door issue. If the compressor is not running, you likely lost your refridgerant due to a leak. If that is the case, you should have a qualified person repair the leak and recharge the system. Adding refridgerant to a leaking system is a wasted effort.

sandman2000

Yes, I am turning the a/c on. Only warm/hot air is coming out the vents. The air does get hotter when adjusting the temperature dial.
No, I do not have auto climate.

raski

We already knew that. If you want help, you need to answer everyone's questions.

Turbonut

What we'd like to know is does the ac clutch on the compressor engage
when air called for? You should be able to detect when compressor is running,
just from the engine rpms, but if not, look at the front of the pulley, it will be
stationary when ac off, but if energized when ac called for, the front will be
turning with the outside of the pulley and belt.

sandman2000

No, the clutch doesn't look like it is engaging. It stays stationary either way.
I checked the fuse and the relay both are good.
I do not have gauges to check the pressure.

Thanks for the input.

Turbonut

With truck off, as stated above, you can remove one of the Schrader vlalve
charging caps and stick the valve with a screwdriver or something that can
push the "pin" down. Need only to do it very quickly to see if any pressure
in the system. If there is pressure, chances are that it may be low not
allowing the compressor clutch to engage, or if no pressure released,
the refrigerant is gone. These are closed systems and wouldn't need any
service unless something is amiss.

This would require someone to check the system with a sniffer that can
detect where the leak is, even soapy water, or a propane torch setup
with a special adapter can be used.

Just to add, not certain as to where the caps may be found on your truck, but look
for the 2 metal a/c lines on the right side of the vehicle and the two plastic caps,
one for low and one for high side.

Let us know

sandman2000

Ok, just went check and 0 pressure, nothing came out at all.
That's strange considering the a/c worked fine that morning and later that day completely done.

Thanks guys. Much appreciated.