How does cabin heating work?

[WXman]

Only 42F here this morning...not even cold yet. But with the truck on "Auto" and temp set to 74F it still never got warm. Also, the windshield gets foggy.

So two questions:

Why do I have to crank the temp up so high to get warmth in the cabin? ALL my prior trucks I would set to 68-70F and stay comfy.

Why does "Auto" mode still require me to select A/C to get the compressor to clear the fog off the windshield?

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[Heliian]

Auto mode doesn't defrost the windows. You need to select defrost on the climate screen or go max defrost with the button.

Also, in the climate screen, make sure heat is selected on.

 

[Firn]

There has been a fair bit of discussion on heat and defrost and I wish I could remember it well enough to recap.

Put simply, there is a lot of disagreement as to if it works well, or doesn't. I have seen some say they have to enable heat to get it to warm up. Others have complained about the windows fogging up. A lot of discussion on how it clicks off recirculate and or how the A/C will re-enable itself.

My gut feeling is the heat pump trucks may work a little different than the resistive heat trucks too, but I have nothing to support that.

I will say that in my 23 the auto setting seems to work how I would expect it aside from maybe fogging up slightly some times IIRC.

 

[RickLightning]

Only 42F here this morning...not even cold yet. But with the truck on "Auto" and temp set to 74F it still never got warm. Also, the windshield gets foggy.

So two questions:

Why do I have to crank the temp up so high to get warmth in the cabin? ALL my prior trucks I would set to 68-70F and stay comfy.

Why does "Auto" mode still require me to select A/C to get the compressor to clear the fog off the windshield?

There has been a fair bit of discussion on heat and defrost and I wish I could remember it well enough to recap.

Put simply, there is a lot of disagreement as to if it works well, or doesn't. I have seen some say they have to enable heat to get it to warm up. Others have complained about the windows fogging up. A lot of discussion on how it clicks off recirculate and or how the A/C will re-enable itself.

My gut feeling is the heat pump trucks may work a little different than the resistive heat trucks too, but I have nothing to support that.

I will say that in my 23 the auto setting seems to work how I would expect it aside from maybe fogging up slightly some times IIRC.

Bingo.

I can't wait for the winter discussions of heat pump vs no heat pump trucks. Our 2022 heats great. I believe heat pump owners will not be happy with what I expect to be:

- slower heat
- noisier heat
- vibration

 

[abcut973]

How do you know if you have a heat pump or not?

 

[WXman]

And if the heat pump setup is objectively worse, why would Ford switch to it? I have a hard time believing it would cost less to produce.

 

[bmwhitetx]

How do you know if you have a heat pump or not?

It was introduced on 2024 models. Your 2022 has a resistance heater.

 

[Firn]

And if the heat pump setup is objectively worse, why would Ford switch to it? I have a hard time believing it would cost less to produce.

Efficiency. Heat pumps are MUCH more efficient at making heat in most weather conditions.

That can change in VERY cold environments (aka our friends to the way way north. Not your climate)

 

[bmwhitetx]

And if the heat pump setup is objectively worse, why would Ford switch to it? I have a hard time believing it would cost less to produce.

Because us 2022 and 2023 owners asked for it . It's what Tesla uses and is more efficient so you're theoretically getting better range in the winter.
Lots and lots of discussion. I wouldn't say it is objectively worse. That is an opinion.
https://www.f150lightningforum.com/forum/search/3836717/?q=heat+pump&c[title_only]=1&o=date

 

[WXman]

OK this thread is going off the rails. We've established that the heat pump setup doesn't heat as well, and that many owners have complained about it. Then immediately the convo turns to how the heat pump setup is more efficient and makes heat better. So which is it?

I can tell you which it is on my June 2025 build truck.....it's worse. If I have to set the temp to 75F or higher just to knock the chill off in the truck with a 42F ambient temp, what's it going to be like at -5F? My goodness....

 

[WXman]

Auto mode doesn't defrost the windows. You need to select defrost on the climate screen or go max defrost with the button.

Also, in the climate screen, make sure heat is selected on.

I'm not trying to defrost (yet). I need to defog. "Auto" mode in every other vehicle I've owned over the last 30 years would automatically take care of that by using the compressor when necessary. This truck does not seem to do that. It's odd.

I did go to the climate screen and heat was selected on already. But the windows did not defog until I manually selected "A/C" and I also hit the "Auto" button until level 2 was selected. This entire thing is a joke and completely defeats the purpose of automatic climate control. At this point I honestly would rather have a basic non-automatic system with a temp knob, fan speed knob, and duct selection. Would be a lot simpler and more effective.

 

[Firn]

We've established that the heat pump setup doesn't heat as well, and that many owners have complained about it. Then immediately the convo turns to how the heat pump setup is more efficient and makes heat better. So which is it?

Those things are not opposite or contrary. The truck warming up the cabin and the efficiency of a heat pump are two different things.

That only came up in response to your question.

Back to your original question. I dont know if anyone will have a good answer. Some are happy with theirs, others have the same complaints as you, others have different complaints, and somewhere in there the hardware changed and that also may or may not have changed the logic.

With what you described I agree, that doesnt make sense.

The only thing I can recomend is reading the old threads, and pay attention to what year the truck is. Every time this comes up there does not seem to be a consensus on how it operates.

 

[Saberdentures]

Finally got cool in Georgia so I’ll be able to test, but this morning I set air on 74, auto, and made sure heat was on. I had preconditioned, so truck was warm, but even on auto 3 I couldn’t feel any air or hear the fan running; the windshield started to fog up, so I manually set the duct to windshield and I heard the fan turn on (or maybe just get louder? Manual airflow was at 2); anyways, the windshield defogged immediately and I got hot quick.

The resistive heater works great in my “23 pro, but that auto mode that I love for A.C doesn’t seem to work for heat.

I *think* last year I figured that heat on auto sent air to my feet and always super low fan speed; perhaps the truck is trying to maximize efficiency for cold weather and does too good a job?

 

[Heliian]

defrost (yet). I need to defog.

LOL, same thing, one is >0degC.

 

[Lightning Bronson]

I will say that in my 23 the auto setting seems to work how I would expect it aside from maybe fogging up slightly some times IIRC.

Can confirm. MY23 truck as well, and Auto works just fine. It's just the matter of making sure heat is turned on, and driver focused is *off*.

Side note: I wish there was a small red light just below the three auto lines that would denote whether heat is enabled so we don't have to toggle the damn HVAC window all the time.

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