My car is obsessed with A/C

[Kamuelaflyer]

Do you use the FPP-89 filter? It could be happenstance but after I installed it I believe it restricts airflow enough that I've noticed my car does not defog as well as when I was using the original filter, like the algorithm just doesn't work quite as well now.

Climate control is a time based affair vs the distance drove and is significantly less, ever with head, than the car uses to move itself as was pointed out.

tl;dr It's the combination of humidity and temperatures.


I do right now, but this goes back 4 years. The issue, for me, is that I live in Hawaii. It's not exactly dry here. Humidity is always an issue. To top that off, I live in upcountry, where not only is it humid, but it's also cool. By the end of this month, our daytime highs will be in the 60s, and the morning lows when I head to town can be anywhere from the high 40s to mid-50s tops. February daytime highs will be in the mid to upper 50s, with lows occasionally in the mid-to-upper 30s. However, the normal low for February at 6-7 am is in the low 40s.

I've gotten used to reaching down with my left hand and pushing the max annoying defrost button during what passes for winter here.

The winters are brutally mild here.

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[ChrisO]

Why is that badly designed? We both need temperature control and it’s was more efficient to use one system to do both rather than two.

The real question is: Are you as the driver able to get the interior temperature to be the temperature you want?

So far in my almost 4 years with this car, the answer is yes.

The OP’s annoyance seems to be tied not to the above but the perception that there is energy wasted based on the system design and AC compressor running when it doesn’t have to.

I was just suggesting the idea that maybe the AC running “isn’t about you” and it’s about the battery temp which would be to help efficiency and reliability.

This is usually the point in the discussion where @MachLee shows up and explains how it works.

You misread my comment.

It is a bad design that can't regulate the temperature of the battery separate from the cabin. It is fine for this to be done with one system. But that system absolutely needs to monitor them both separately and provide just what is need for each.

My statement was in reference to the suggestion that the cabin A/C might have to be on just because the same system is use for the battery.

 

[TheRock]

1. Bought car.
2. Set auto to 72.
3. Haven’t thought about it since.

+1

 

[Teslaeata]

Is this one of the driver settings that you set like mirror & seat positioning?

 

[Mach1E]

You misread my comment.

It is a bad design that can't regulate the temperature of the battery separate from the cabin. It is fine for this to be done with one system. But that system absolutely needs to monitor them both separately and provide just what is need for each.

My statement was in reference to the suggestion that the cabin A/C might have to be on just because the same system is use for the battery.

You can regulate the cabin temp separately from the battery.

Set it to auto, pick a number. It does monitor the battery needs and the cabin temp needs separately.

The OPs complaint is that the AC is on and “wasting energy.” I was just pointing out that our AC system does things other than just change the temperature of the cabin.

 

[ChrisO]

You can regulate the cabin temp separately from the battery.

Set it to auto, pick a number. It does monitor the battery needs and the cabin temp needs separately.

The OPs complaint is that the AC is on and “wasting energy.” I was just pointing out that our AC system does things other than just change the temperature of the cabin.

I think we basically pretty much saying the same thing, just a couple of details we might differ on.

1. Having the AC on isn't "wasting energy".
2. The battery and the cabin are controlled separately and so the reason the AC is turned on automatically can't be, because AC is needed for the battery, as some people have guessed at. It might be because another reason, but that isn't it. But another suggestion that it might be for preventing fogging doesn't seem to hold up. We are talking that the weather here is in the 70s to low 80s. There is zero chance of fogging.
3. A large amount of people feel that this should be under the user's control (cabin AC) not turned on automatically. I'm of that opinion. My opinion isn't based on the belief that it wastes energy, it is more about having air blowing on me, when I don't want it.
4. This doesn't behave the same for all people, that suggests that it might be a bug one way or another. I can turn off the AC and it never turns back on. I seem to be in the "minority group", but I can tell you that it behaves exactly how people are saying that they would like it to work.

 

[Mach1E]

I think we basically pretty much saying the same thing, just a couple of details we might differ on.

1. Having the AC on isn't "wasting energy".
2. The battery and the cabin are controlled separately and so the reason the AC is turned on automatically can't be, because AC is needed for the battery, as some people have guessed at. It might be because another reason, but that isn't it. But another suggestion that it might be for preventing fogging doesn't seem to hold up. We are talking that the weather here is in the 70s to low 80s. There is zero chance of fogging.
3. A large amount of people feel that this should be under the user's control (cabin AC) not turned on automatically. I'm of that opinion. My opinion isn't based on the belief that it wastes energy, it is more about having air blowing on me, when I don't want it.
4. This doesn't behave the same for all people, that suggests that it might be a bug one way or another. I can turn off the AC and it never turns back on. I seem to be in the "minority group", but I can tell you that it behaves exactly how people are saying that they would like it to work.

For #2 we do know the AC is automatically trying to lower humidity and cool the battery.
#3 I agree. Same goes for recirculation which automatically turns off

#4 As far as a possible bug- that I do believe. My AC has never functioned properly. Auto fan speed (even if it’s 95 degrees outside) starts at the lowest setting when I start the car until I change the temperature then it speeds up.

 

[ChrisO]

@Mach1E Yeah, we have noticed that about the AC "automatic fan" too. It isn't very "automatic".

 

[SpeedRacer72]

1. Bought car.
2. Set auto to 72.
3. Haven’t thought about it since.

That is Very helpful, the MME community thanks you for your enormous contribution to the user knowledgebase!

 

[atacama]

Just started the car & A/C came on. Data:
* outside temperature: 67 F in my weather app, 65 F reported by car.
* dew point: 54 F. RH: 64%.
* car thermostat set temperature: 71 F

I’ve been incorrectly characterized as only concerned about wasting energy. That is secondary. I hear reports that it’s an immaterial loss. But still, it’ss system that isn’t needed.
Primary annoyance is cold air blowing on me when it’s reducing my comfort.

I’ll assert that Ford’s algorithm for A/C use is wrong. Why is it needed for the data above? It ain’t temperature, humidity or mildew.

Finally, Ford should not be overriding my preferences. When there is conflict, the consumer should be given the win.

 

[Mach-Lee]

Just started the car & A/C came on. Data:
* outside temperature: 67 F in my weather app, 65 F reported by car.
* dew point: 54 F. RH: 64%.
* car thermostat set temperature: 71 F

I’ve been incorrectly characterized as only concerned about wasting energy. That is secondary. I hear reports that it’s an immaterial loss. But still, it’ss system that isn’t needed.
Primary annoyance is cold air blowing on me when it’s reducing my comfort.

I’ll assert that Ford’s algorithm for A/C use is wrong. Why is it needed for the data above? It ain’t temperature, humidity or mildew.

Finally, Ford should not be overriding my preferences. When there is conflict, the consumer should be given the win.

So if it’s blowing cold air…why not increase the temp setting? To like 75°F?

The A/C will be on pretty much any time the outside temp is above 50°F to provide dehumidification. It will also turn on as low as 32°F if the interior dew point is higher than the outside temperature to prevent window fogging.

 

[eponey]

I think there is a fundamental lack of understanding of what the purpose of and words air conditioning mean, not sure we are going to make headway here.

 

[ChrisO]

For what is worth, we picked up a 2025 Premium Mach-E on the 11th, and the behavior with it is if we turn off everything A/C and fan, it will stay off. If we leave the fan (and of course the A/C) on when turn the car off, then both will turn on when we start the car.

Frankly, I can't remember if I tried the combination of just the fan on for the 2024 Select. Since the main reason we have it off in the first place is because we like the windows open instead of a fan.

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