I am convinced that Automatic Climate Control (a.k.a. Automatic Temperature Control) is one of the greatest automotive inventions. You set the temperature you want and press the “Auto” button, and the system handles everything else: Fan speed, A/C compressor engagement, hot/cold air blend, and even the direction of airflow. While mechanical ATC systems of the 60s and 70s were kind of wonky, modern computerized systems do their job remarkably well.
Automatic Climate Control seems to be one of the most misunderstood automotive features. Allow me, then, to pick a particular nit of mine: While most cars anymore have some form of automated temperature control, almost inevitably while riding in someone else’s car so equipped, the temperature, blower, and air directions are all overridden to manual settings.
I can’t count the number of times I’ve sweltered in someone’s car because they had the temperature set all the way to “HI,” or frozen because someone manually set the blower speed to a ridiculously low setting. It is all I can do in these situations to resist reaching over and pressing the “Auto” button to set things right.
I suspect that there are numerous causes for people overriding their ATC using the manual controls. On cold days, most ATC systems will disengage the blower until the water temperature has reached a certain point, to avoid blowing cold air on already cold occupants. However, some people (especially those unfamiliar with the operation of ATC) may misinterpret this to mean that the system is switched off, or they think they may get some heat a little sooner by manually increasing the fan speed.
The other bit of psychology I suspect is going on here is people thinking the car will heat up faster if you turn the temperature setting up higher. I’ve seen this thinking applied to other settings, such as warm conference rooms that people think will cool down more quickly if the thermostat is turned all the way down. But again, unless you are dealing with multi-stage heating and cooling systems (which most cars and homes do not have), this thinking is false: Most ATC systems will run the heat (or A/C) at full blast until it gets near the set temperature. Turning the temperature beyond the set temperature won’t make the heater output any more heat, or get to the set temperature faster.
I’m not sure whether it is a matter of people failing to understand how automatic climate control is supposed to work (pick your temperature and press auto), or if people make a conscious choice to override the automatic settings (hence the purpose of this question). So I’ll put it to the crowd:
Are you a control freak, constantly fiddling with the temperature and fan settings, or are you an auto-pilot like me, pressing the “Auto” button and letting the ATC system do its job? And what is the reason for your choice?
My automatic climate control is named Mrs. Jason. 🙂
Other than my ’75 Thunderbird, I’ve yet to own a car with automatic climate control.
On the Acura I just push the Auto button. In the Lotus I’m all natural.
Your gripe goes to thermostats generally. It seems that nobody understands how they work. I don’t care what the weather outside is doing, there is no need to change the thermostat inside to compensate for it.
I am like Jason, I still do not own a car with it (and those I have owned with it had their problems).
The other gripe with those systems is with folks who turn the system “off” each time they park the car. Like you, I can hardly resist saying “just leave it alone!”
My Dad would tell me that when I was a kid when I would stealthily bump the the thermostat up to 70-71 from his setting of 66. I did in fact fully understand how it worked though, I had zero intention of turning it back down to his bone numbing setting 🙂
If you turn it to off some cars will close the fresh air intake, which can be a good thing, though it can be bad too.
My wife and I were jokingly moaning about having to manually adjust the heat in our F-150 the other day, as our other vehicles have automatic climate control. Then we remembered the 1964 Chevy C-10 we have when we got married, in which the heater did not work at all.
“On cold days, most ATC systems will disengage the blower until the water temperature has reached a certain point, to avoid blowing cold air on already cold occupants”
If I’d ever been in an ATC-equipped car with this feature, I would have no problem with ATC. Every one I’ve ever been in, when set to “Auto”, immediately turns the fan speed to high in order to “heat” the car up to the desired temperature quicker. In effect, you’re getting blasted with cold air until the engine warms. It’s been a while since I’ve been in an ATC-equipped car in the winter, so they may be better now.
The majority of climate control systems today interface with the PCM to get info on coolant temp and won’t employ a blower for heat until it can actually provide heat. Earlier systems would still have a means of getting coolant temperature and again would disable a blower motor if heat could not be provided. I’d suspect you’ve been exposed to vehicles with a temp sensor input issue, a faulty contorl unit, or a system that wasn’t as automatic as it claimed to be.
I can tell you from personal experience that a Lincoln Versailles, with a temp slider, would hold off on running the blower until it warmed up. I can’t imagine anything with a digital panel wouldn’t include that logic.
I’ve never had a system that will run the blower on high when the coolant is cold and the request is for heat. Mine will run the fan on very low with all the air going to the windshield and while it may not feel like “heat” it is warmer than the ambient temp.
Exactly.
I don’t like the way when I get in the car and turn it on, everything defaults to “max super turbo power ultra-noise fan” mode.
I can decide for my own damn self whether I want more or less air flow, and whether I want it hotter or colder. There are a whole range of potential settings like heater on low but lots of air flow vs. heater up higher but little air flow, etc. I insist on choosing these things for myself.
The “auto” setting is probably why, up North in the Winter, most of the time when I get into someone else’s car wearing a heavy coat, hat, and gloves, they’ve got it set on “Mojave Desert” setting and I spend most of the ride trying to shuck off all my heavy clothes, just to have to put it all back on again when I get out.
I never use them for one simple reason – I like airflow. There’s nothing worse than an auto system that hits its temperature and then stops doing anything and you are sitting in a closed box of a car in unmoving stale air. I’ll use the controls as if it were a manual system and adjust as I feel necessary. But that’s just my viewpoint.
Back in my “casual carpool” days there were times when I’d get into someone’s car and the ventilation system would be “off”. Horrible rides, came close to vomiting several times. I don’t know if it’s a cultural thing but virtually every time it was a driver of I believe Chinese descent. (Not singling anyone out, just my finding). Curiously, when I flew on Air China last fall I realized that the planes (both Boeing and Airbus) did NOT have the little airflow nozzles overhead. It immediately reminded me of the carpool days some fifteen or so years ago. It was strange to my “western” self.
If you’re riding in my car though, don’t you dare to reach over and adjust it for me! You’ll be driving yourself in short order 😀
I’m with you. And can top that story:
The young woman who rents the little cottage behind our house drives a ’95 or so Camry. Her BF said it needed an alignment. I offered to drive it to confirm (it tracked straight as an arrow on the freeway).
Anyway, I had noticed that she always drove with her window part way down, no matter how cold or rainy. I got in and asked if she minded if I rolled up the window once we got on the freeway (it’s winter). She said no, but said she kept it down because the car was stuffy and smelled a bit off.
I looked at her HVAC controls. The Recirculate was on. The fan was on 0. I switched the recirculate off, turned the fan on, set the outlets to part face/part feet, and adjusted the temp. Her eyes opened wide, and said “Oh, it’s so nice and comfortable now!” I explained how the system works….
She had never bothered to learn the rudiments of a car HVAC system. Or no one had shown her…not her dumb BF, in any case.
It’s not the first time I’ve encountered people having the Recirc on. How can anyone bear to sit in an airtight enclosure for anyhting more than a few minutes? It’s like being locked in a non-running refrigerator!
The only reason for the Recirculate button is for the part of the populace that ever drives down (or up) I-5 right at Kettleman City where you pass miles of cattle feed lots and without recirculating the inside air or turning it off (my one exception to my rule) the stench is overwhelming. It’s also a license to speed right there as no CHP officer will pull anyone over in that location.
True that! That’s where I learned to use it and appreciate it.
“The only reason for the Recirculate button”
There is one other reason – when you get into your closed car on a sunny 96 degree day and need to cool the inside down as fast as you can. But as soon as it cools down turn it back to fresh air. Unless you had an older foreign a/c system that could only keep up with a hot day on recirc. Never a problem with the US systems back in the 80s and before.
This is what they invented power windows for. 🙂 Why recirculate the 140 degree hot air until it cools when you can get fresh 96 degree air? Then just add 480 A/C for a couple of miles and you’re golden.
Yeah the first application of recirc was for cooling down the car and was activated by selecting Max A/C, to get the car down to temp quicker or to allow it to keep up in extreme conditions. Of course the owner’s manual detailed it all.
I have always closed windows for the 1-2 minute drive past KC.
Not a spam edit but outside the 2004 Le Sabre none of my cars has auto. All are manual and I haven’t even used AC in my daily Focus in the last 7-8 years now. If I know I truly will need AC, and it is a 200 mile round trip, then I use the Le Sabre which maybe five times a year.
Oh, now you’ve struck a nerve. It might no longer be the case, but for a lot of years it seems an awful lot of Honda owners, particularly, had this unshakable belief that they should always leave the system in Recirc mode. I always asked and never got anything even close to a cogent explanation; it was always vague (“it works best that way”), just-so (“because that’s where it’s supposed to be”) or just plain wrong (“it prevents mould from forming”, “it reduces wear on the compressor”, etc). Nothing would convince these people—not the stale air, not the fogged windows, not a practical demonstration of what happens when you switch to fresh air, nothing.
Maybe it was because they were used to Chevrolets and Fords that would blow honest-to-icecube cold air on the fresh setting, and were tired of the 15 degree rise in air temperature coming out of the vents when you tried moving to fresh air?
Agreed. I don’t know what it was about Honda owners back in the ’80s and ’90s, but you could always recognize them a mile away by their fogged up windows in the winter.
Really !!! I recently chastised a Youtuber / Driving instructor, who had posted several videos instructing drivers on the “best” way to defog a car in winter, by using defrost, max heat, and recirc, AC on, and a window cracked. When I pointed out that the window would not need to be cracked, nor the AC on, if he switch the recirc to fresh air, he claimed his elderly Honda couldn’t generate enough heat without it. I decided not to waste more effort on the discussion.
Remind me not to take any lessons from that driving instructor.
That said, you don’t get an A+ on this, either. Running the A/C compressor is absolutely the right way to do it if the goal is fastest and most effective defogging. The cold evaporator wrings (condenses) moisture from the air so what hits the windshield is dry air of whatever temperature (hotter being better, though one must take care not to create too much temperature gradient across the glass on very cold days, else risk cracking it).
Read up on the principle here. (“Reheat Principle of Temperature Control”).
Very familiar with the principle, and you’re generally correct. But in winter where both the instructor and I live, the winter air at -15C contains so little moisture that just running it through the heater drops the humidity well below the point where it will fog the glass. When it’s warmer, and in areas with more moisture in the air, running the AC is the way to go. As most cars now do automagically when set to defrost.
You’ve got me there! At 18 below (or above, if we’re measuring in °F), it’s likely the compressor won’t even engage—with or without computerised controls.
Same here; the car just feels too stuffy when no air is moving. As for the individual vents on airplanes, they’re apparently an optional feature now, according to YouTube travel videos I’ve seen. So your individual comfort depends on how parsimonious the airline decides to be.
Funny you should ask. I’m of the “set it on ‘AUTO’ at 70 to 72 degrees and let it do its job.”
Ironically, when I was having issues last summer with my air conditioning compressor not coming on when the outside temperature was over 90 degrees, the tech at the local Ford dealer said I was “using it wrong” because I didn’t hit the “Max A/C” button when I first started the vehicle. I really wanted to say that I’ve been letting automatic climate control be automatic for some two or more decades, but decided against it.
That tech doesn’t understand how the system works.
I’ve had four cars with automatic temperature control: 1985 300ZX Turbo, 1996 Altima GLE, 1999 Maxima GLE, and the current 2010 Infiniti G37.
Of the four, the most finely tuned system was in the Maxima. I set it on 69 degrees and never touched it again year round (here in SoCal we rarely need “heat”). The other three all needed a little adjustment when the weather turned quite hot or quite chilly as they seemed to overcompensate and freeze or roast you. Most of the year I don’t have to touch the controls on the G37 except when we hit “extreme” temperatures. Overall it works very well, better than the three previous cars I owned with manual A/C.
BTW, the iciest A/C among my own cars was the 300ZX with its freon-based system. It got cold instantly and easily maintained meat locker conditions inside the car on 100+ days.
I have a 1999 Infiniti G20, and from pictures it at least appears to have the same HVAC controls as the 1999 Nissan Maxima. Not terribly surprising I guess, since it seems that Nissan raided the parts bin to spruce up the Primera into an Infiniti.
Like you, I’ve got it set to 69 degrees, and almost never touch it. And I’m in Minnesota, so it gets to deal with well below freezing as well as hot humid midwestern summers.
The only situation it doesn’t seem to handle well is automatically turning on the defroster in cold weather. It’ll do it once it gets really, really cold, but sometimes I need to override it when the weather is just cold and the windows start fogging up.
Auto climate controls are a concept lost on me, first of all I came up on cars with the ergonomically perfect “three knob” manual systems and anything else just seems gimmicky to me. And unlike a house thermostat, in a ICE car there is zero efficiency to be gained by setting a minimum temperature and leaving it there, if I’m cold I’m cranking the temperature way the hell up, and if I feel it’s too much after a while, then I’ll bring it back down to whatever I feel is comfortable.
When a car’s Automatic Climate Control works well, I use it. But when it doesn’t, I’ll control it manually. I’ve had one of each. Also, our most recent car doesn’t have ACC, and somewhat surprisingly, I don’t really miss it. Adjusting HVAC controls isn’t too bothersome, after all.
My current daily driver is a 2010 Honda Odyssey with auto. climate control that has always worked well. I typically leave it in auto mode, unless I’m driving with the windows down, or if there’s some odd circumstance, like being baked in the sun on a long drive.
My previous daily driver was a 2006 Crown Victoria, and the ACC never worked well in that car. Eventually, I gave up trying and just used it on manual mode. That is, until the system quit working altogether, but that’s another story.
Last year we bought a Kia Sedona, which does not have auto. climate controls. Having grown accustomed to the set-it-and-forget-it nature of our Odyssey’s system, I sort of dreaded going back to the stone-age ritual of setting fan and temperature controls. But it’s really not a problem, and neither my wife or I miss having ACC on that car.
Never had it. Well, maybe my Eldorado did, but I never used it.
I was surprised when my new (2017) Civic came with climate control. I rarely, if ever, use it, except for the allowance to split the temperatures between the driver and passenger. My main gripe is I see no reason to be comfortably flying down the freeway with the heater on and the air conditioner compressor grinding away.
My previous car, a 2004 PT Cruiser, had a standard unit that used a dial to choose airflow between the panel, floor and defrost vents. I very much prefer this over the push button choices I have now.
One of the most elegantly simple designs for the split temp option was offered on my 1983 VW GTi. The temperature control only distributed heated air through the floor and center stack panel outlets, so if the driver or passenger was too hot, they had the option of opening their vent nearest the doors.
You should really try it Jerry. I’ve had 3 cars with Climate Control, an ’88 T-Bird, a 1998 Regal GS and my current 2016 Civic. While I had to mess with the settings on the ‘Bird and the Buick, that Civic’s Climate Control system is THE BEST.
It is the very definition of “Set it and forget it”.
My 2002 PT Cruiser’s airflow circulation dial had many detents so one could gradually modulate the direction of the HVAC airflow, one click at a time. And the A/C switch was the fan speed dial (left most dial shown below); turn right to increase airflow with no A/C; turn left (shown in blue) to increase airflow with A/C. Dead center is off – everything.
So simple and so logical, and Chrysler did not have to pay for a separate A/C switch (but one did need to know about the “blue” part of the dial).
ATC? Not on any of my cars. So far.
That control head worked well, and it was done on the cheap, lifted directly from the Neon parts bin. The 2006 model PT went to a separate A/C compressor switch and a completely new control head, but 2006 was also the year the entire electrical system was changed and redesigned (and the troublesome TIPM introduced…another Daimler Bad Idea).
Only car I ever had that had it was my Saab 9000. Hated it – it never worked right, though I got the car after several owners had had their way with it first.
On my Honda you need to use a touch screen to over-ride the auto settings, and I can’t use a touch screen while I’m driving.
Can you do it with the voice command function?
I’ve had three cars with ATC. My old ALFA 164 worked like a charm (believe it or not), it was amazing on a long trip to see it start out with heat in the morning and then shift into vent, then A/C as the day wore on. My first gen Prius had auto temp that worked well but fan and direction were up to me. My second gen Prius worked OK, but it seemed as if the cabin temp sensor lagged so I had to fiddle with it. Now my ’14 Spark EV has a pretty good one, but it starts out blowing cold air. Of course I try to use it as little as possible as resistance electric heat saps too much power – heated seats, a light jacket, and defog as needed does the trick most of the time.
You know it’s funny, before I had an EV I thought I’d do like you said and use as little heat as possible. But in fact once I really drove an EV and found I have plenty of range after all (thanks to plugging in at home), I didn’t care. So I enjoy the EV’s instant heat and stay comfy.
It’s simple: Set it and forget it.
Until my wife gets in the car. Then all bets are off.
Agree. I really like auto climate control and prefer it on all our vehicles. The temp setting varies with the season… cooler in the winter because the layer of clothing makes up the difference, and a little warmer in the summer again because of the lack of layers of clothing and the dehumidifying function of the AC yields the desired comfort level.
Deviation from auto fan occurs as needed to hear a phone conversation (hands-free of course). Deviation from auto mode occurs when needed to Defoe the windshield.
I cringe when I see people override the fan or set an exaggerated temperature in hopes getting to a more comfortable temperature sooner. Well, it does not change the time to get to the more comfortable climate… it just enables the system to “over-shoot the runway”.
Yep, that sounds familiar. My wife is constantly futzing with the climate controls in her Subaru Outback, often putting the temperature all the way down or all the way up depending on the season. I rarely touch the controls in my car. At least both of our cars have dual-zone temperature controls so we can take care of our side of the car, but I have been known to say “just leave it alone!” in a semi (or not) exasperated tone.
Yes, I use it. It’s not only more comfortable but relieves me of a tusk while driving, which is often not the case with a regular A/C. But I must say that with some cars the CC (that’s Climate Control, not Curbside Classic…) works much better than others, so you don’t need to step in and adjust anything. Than there’s the importance of the controls, and I’ll explain;
Attached is the Opel Astra’s CC panel. Note how easy it is; to operate it, you don’t need to look at it, because the “Auto” button is in a unique position and the widest off all other buttons. You only need to press it once to start the CC going, and from then on it’s just a matter of turning the left temp knob – the system will deal with everything else, and (at least in the Astra) does so faultlessly.
Now here’s the Honda Civic’s panel- and it couldn’t be worse. For a start, you need to look for “Auto” because it blends with the other buttons, as is the “Up-Down” operation of the temp button – a rotating knob is sooooo much better for this action. The only thing I’ll concede to this layout is the “Front” button, which is located bottom left and is an easy reach.
BTW, that button is yet another pro for the CC – if you need to defrost the front windshield, pressing it will do a much better job than any messing with the vents, A/C hot/cold or whatever. It works great in both the Astra and the Civic.
Arguments over home HVAC settings must surely be one of the many small straws of life that eventually build up to break the back of more than a few marriages.
Thank you for this submission Tom, even though the people who really need to read and understand it, will probably never do either.
Ask your lawyer to send it to her lawyer. 🙂
Auto with A/C off. I want manual control over the A/C.
Press [Auto] to enable A/C (if needed)
Press [A/C] after [Auto] to disable A/C (default setting)
Leave everything else to “automatic” climate control.
Depends on the system. Unlike scottn59c above, I found the system in my Saab 9000 to be excellent. It was a true “set it and forget it” system that intuitively knew when to run defrost, full-on heat toward the floor or to blend the airflow. I owned several other cars with ACC and some were better than others (a couple of the others were Saabs as well, ironically). The Chrysler 300 I owned had that annoying “full-on-tornado-blast” tendancy whether cooling a hot car or heating it up. That got frustrating, so I would just over ride the system and set it myself.
When I bought my XE in December, I set the climate to 70 Auto. I haven’t touched it since aside from once when I needed the Defrost after some time in the car and the windows started to fog. Jaguar’s climate controls force A/C with Auto, so my A/C’s always on. Jaguar’s climate controls, both in my X-Types and the XE, wait 2-3 minutes after starting the car before they ramp up the blower so the air’s not quite as untempered when it starts.
To add to my comment, I’m on my 4th car with automatic climate (the Fiesta ST’s wasn’t great, but it was good enough). When I drive my 1995 F-150, I literally set the climate temperature knob to one spot just to the cool side of centered, and that’s where it stays. I change the mode, but I don’t usually mess with the temperature.
The passengers side of my car has a habit of getting stuck on hot if I turn it up on cold mornings so I rarely adjust anything just hit the demist every now and then to clear the windscreen is about it
“Is the heat on?”
“The engine is still cold.”
“Is the heat on !?”
That is a frequent conversation in the cars of Mr. and Mrs. W. And when ever I am using her car the HVAC is set to …something.
A common conversation with Mrs. JPC as well. “Wait until the little blue light goes off” I say. Mrs. JPC responds nonverbally by cranking the blower to high.
I have had ACC for about 3 years. It works well, but always the fan speed is set to max, so after a few minutes I get tired of the noise. I will also turn recirculate to “on” for a few minutes when it’s too cold outside.
Recirculation is helpful in humid Florida, as on sweltering summer days with 100% humidity, the outside air being drawn in is never comfortable.
I have driven a Kia Optima with the ACC, and it works well for the most part, set it and forget it. It really boils down to the ACC and how well it was designed, but people usually think that an automatic system doesn’t know best, so they manually override it, then forget to turn it back on, and it reinforces their assumption that they know better than the system. Kind of like drivers who turn off the stability/traction control as they know more than the engineers who developed the car….
Personally, I’m quite happy with manual control of HVAC, and I’ve been bothered by CC. There is something about wanting to change (usually lower) the temperature during a long drive and it’s not exactly difficult (except for Camry drivers – see above). I’d vote for an electrically heated screen (Ford style) over CC any day
My MX-5 has the best CC though – release 2 catches and push back!
The ATC in my wife’s Mazda absolutely brings out the curmudgeon in me. I’m never happy with the temperature setting, it’s either too warm or too cool. I can’t see the puny little display for airflow, or the tiny icons on the HVAC buttons when I’m driving. By contrast, operating the manual system in her old Toyota Matrix is a breeze (pun intended). 3 large dials, and 2 buttons for A/C and recirc high on the dash next to the instrument cluster. At this time of the year, I may have to adjust the heater dial one click in either direction, but it’s so easy to use!
As I mentioned to Jerry above, the system in the 2016 Civic is the best I’ve ever experienced. It is so perfect, that I have to remind myself on nice spring and fall days when I roll the top back and roll the windows down to turn it off. It really is a “Set it and forget it” system.
I’ve noticed that it will automatically toggle as needed between fresh and recirc, so that’s the one time I may use a manual setting. If I am about to drive past the sewage treatment plant, I’ll look down to see if the system is drawing fresh air (indicator light off), and if so, will hit the recirc button to illuminate it. Once past the potential environmental danger, I put it back to Auto and let it do its thing.
The only thing I ever have to adjust is the temperature, and even that is very rare. And it has Dual Climate Control, which I almost never use, as I usually keep them in sync. My wife, when she rides in that car, even though she knows she can adjust her own temperature, almost never fools with it. She does dig the heated seats though. Personally, I’m not a fan unless it’s below 15 degrees F outside.
Auto climate control in my F-150 works great. It’s a set it and forget it affair…set the temp you want (dual zone temp control allows the driver and passenger to each set their own temp) and the system does the rest. In colder weather the truck warms up pretty quickly and in warmer weather the a/c cools things down in a hurry. Either way, it only takes a few minutes for the cabin to reach a comfortable temperature. There’s never any window fogging, and the heated and cooled seats are just icing on the already outstanding cake. Be nice if the climate control systems in my other vehicles worked this well.
My Expedition is pretty good as well, except for the irritating tendency for it to send a wee bit of chilled air to the footwells on a hot summer day. Once every summer, I forget about this and head down the highway wearing sandals…and end up chilled to the bone from the toes on up.
I leave the setting on AUTO in my 2010 Mazda CX-7 on 100% of the time. You are not smarter than the car’s computers.
I have had ACC in six cars to date and have typically used it in “set it and forget it” mode. What I have noticed is that the systems have improved over the years, with my two most recent cars with ACC, a 2017 Fusion and a 2019 Honda Passport, able to maintain the same temperature setting year round. In North Texas, summer temps can go above 100 degrees from June through September and we seem to get a few days every winter when the temps don’t climb above freezing. In this environment, as was said above, it’s all about airflow to me, even in the winter, the car can become intolerably warm and stale without ventilation.
We’ve owned three cars with climate control. Maybe four if my wife’s Golf has it, though I doubt it and I don’t drive it enough to remember, and even if it does I’d doubt we use it. I am pretty experienced with car ventilation settings and frequently change mode, fan speed, recirc, AC compressor on (either through AC switch or defrost mode) and temp settings to get what I want. “Auto” mode in the two Toyota’s and one Subaru we’ve owned with this feature seems to max the fan noise, I mean speed, and then turn on the AC just for fun. Oh, and recirc too. I’ve tried to be patient but I seriously think I can do it more effectively.
With the ‘04 Forester, I read of a hack online to add a small 12V computer fan to blow more cabin air on the temp sensor under the dash. Seemed easier to twiddle the knobs myself. The ‘08 Prius was a bit better, but defaulted to recirc too much and I hate stale air.
The ‘16 Tacoma cranks the fan too loud, and it has two other features that I can control better myself, that aren’t really integrated with the climate control, at least for cold weather: 1) heated seats, and 2) an auxiliary heating element which comes into play before the coolant warms up and is very effective. But it’s only turned on if you crank the temp knob to “HI”. It’s a poorly documented feature on late-model Toyota’s which I only learned about recently, after owning the truck almost 4 years.
The ACC in my deVille was fine, because if I didn’t like what it was doing, I could reach over and adjust it. My Prius is a PITA, because if I don’t like what it’s doing, I have to change screens on the MFD and poke at “buttons” with no feedback to try to make it do what I want.
So I mostly leave it alone and set it to 77 in winter and 82 in summer. I turn the whole thing off at lights, because it sucks the HV battery dry when the engine isn’t running.
I love automatic climate control and always use it in my BMW. BMW’s automatic climate control is probably one of the more complex systems, as even in auto you can still control just how hot or cold the air is at your set temperature and just how much air flow is coming through the vents. I personally like this, though it tends to confuse many.
Another commonly misunderstood part of automotive HVAC systems is that having “A/C” on doesn’t necessarily mean you’ll only be getting cold air. It just means that you are allowing the car to be capable of blowing cold air should it require so to reach your set temperature. Hence why so many people who turn A/C off experience foggy windows on a cold day.
When the compressor is running the evaporator (which cools incoming air) will condense excess moisture out of the air. This will reduce fogging on the windows. However, when the outside temperature is below about 40 F, then the compressor will not run because the evaporator will ice up. But warming the incoming air up from 40 degrees will dry it out so the windows won’t fog up too much.
I practically never touch my automatic climate control system. It’s always turned on at the same temperature all year round. That’s why I get it in all my vehicles.
People not taking the time to learn how something works? What a surprise! NOT.
I’ll let you know how I use my Auto Climate Control when I get the car that has it!
All my cars have had the traditional analog systems so I can’t really comment on the digital systems.
I hate ATC systems. They’re all supposed to know what I want. None of them does—not even close, that I’ve ever encountered. For example, when I turn on the defogger, no, I really DON’T ever want maximum fan speed “helpfully” selected automatically. I rarely want maximum fan speed at all, but on the occasion I do, I’ll pick it myself, thanks.
More broadly, household-type HVAC controls (set the temperature and let the system figure out how to maintain it) are really not appropriate in cars. Mobile HVAC is a very different task, not least because any given objective temperature feels very different depending on factors like whether the sun’s shining in through the windows. Those kinds of variations are much wider and more dynamic in a car than in a house or office building.
Too, my preferences for air volume/movement and air heating or cooling aren’t consistent. Sometimes I want more of one, sometimes I want more of the other; sometimes I want more up here and sometimes more down there. Rather than an ATC system programmed to win every argument no matter how wrong it is, I’d really rather have thoughtfully-designed controls that let me quickly and easily just pick what I want at any given moment, without looking.
I’m even more of a luddite than that, actually; I prefer the old method of modulating A/C temperature by adjusting the frequency and duration of compressor clutch engagement. That strategy was phased out in favour of full-time compressor operation and temperature modulation by blending cold and hot air. Sure, that allows more consistent interior temperature. Who said that’s necessarily better? Certainly not I; I like the periodic burst of colder air one gets with the clutch-cycling method—I feel more refreshed by a system with a few degrees’ hysteresis around the setpoint. When I’ve got one of those set just right, which is not difficult, the compressor will kick in a second or three before I would want to reach over and nudge the lever or dial a little more toward colder.
All my cars have had ATC. I tend to turn the knobs one way once fall sets in and turn them the other way once spring comes. 🙂
The only time I ever really need to go manual is when defogging; like Daniel I really don’t need the fan to go full blast most times to see.
I leave it on AUTO year round. I might adjust the temp, though I tend to turn it down in the winter. 70F is fine in the winter, and the rest of the year 73 or thereabouts. I will note my wife and all three kids are incapable of leaving their cars on AUTO and constantly leave everything in some sort of weirdo manual mode setting, so my vote for AUTO is a minoirity in my house.
I will also note that my parents, when they have ATC, have for years selected OFF every damn time they turn the car off. Drives me nuts. Dad says he doesn’t want to “strain the starter”. Which even if that were a concern (which I doubt it is), seems like the excess wear and tear turning the ATC system off and on every time you exit the vehicle is not a good tradeoff.
My Altima has auto controls but I like to leave it on defrost and heat during the winter but the fan still runs automatically
I leave mine at 72 year round except for a few times in the summer when I’ll bump it up to 73 or 74 when I get tired of all the cold air shooting out at me.
My BMW 5 has a very nice Automatic Climate Control system that addresses a lot of the complaints above. Of course you have the dual zone set-the-temp-and-forget-it knobs, (so it stays 68 in winter and 75 in summer for me) but you can also independently control the temperature and airflow of the upper vents if you like a certain amount of cooler air on your face as I do. You can also adjust (and then forget) the maximum fan speed on automatic so you don’t get a hurricane (unless you choose max defrost or max a/c). The heater fan doesn’t come on until the coolant is warm but this is somewhat mitigated by the seat heaters and steering wheel heater which can be set to come on automatically at a chosen temp (I chose 45 degrees)…the passenger side only comes on if the seat is occupied. The recirc function also has an automatic setting and it has some sort of dust/pollution/odor? sensor which I don’t understand that keeps unpleasant odors from coming through the vents. It seems to work as far as I can tell anyhow, as I have not caught it failing to detect something..yet. The car also has a nice feature where the outside mirrors automatically defog/defrost at 38 degrees. The rear passengers had vents in the end of the console
which they can aim and both temp and air flow can be somewhat adjusted but with none of the sophistication of the front controls.
It was a bit of a bother to set up when I first got the car, but once set, it’s become almost invisible. Another nice feature is that each key automatically switches settings to that driver’s preferences so my wife, who doesn’t like cool air on her face doesn’t have to manually adjust anything when she drives the car.
I really enjoy it… but I would be scared to death if I were, say, the third owner of this car…or even the second owner the day after the warranty ends. I’m lucky enough to be in a position where the car will be gone before the warranty is.
In most of my cars it is set it and forget it except for unusual situations like defogging/defrosting.
Now in the car with the opening pano I’ll manually do things when the top is open on extreme temp days. Just yesterday when it was in the low 40’s I set it on Def and 80. and its like driving on a 60 degree day with the top open. On 90 degree days I’ll do the opposite.
First car I drove with ATC was a ’77 Pontiac Bonneville, which had a typical GM HVAC system except that the hot-to-cold lever was replaced by a thermostatic lever marked in degrees F. It didn’t work very well because the temperature sensor was on top of the dash and it got fooled by the sun beating down on it. Fan speed, which ducts were used, and A/C compressor on/off was still manually controlled, nonetheless it was marketed as automatic temp control, not semi-automatic. My VW has a similar semi-automatic Climatic temp control which works the same way but much better; I usually keep the control at about 70F and the fan speed at either 1/4 or 2/4. I turn the fan on high to cool the car down quickly on hot days, and turn the vents to the defog position when needed. I only occasionally turn the temp knob to full-hot or full-cold.
I had perhaps unusual early exposure to GM’s Comfortron in a 1966 Oldsmobile Ninety-Eight Town Sedan whose major option was the Comfortron system.
At several years of age, it seemed to work like a champ, but the owner, a friend’s mom, kept the car well serviced, so who knows how much trouble it was.
You really could not defeat the early Comfortron, there was a temperature wheel that also seemed to control fan speed. The driver chose the mode – defrost, dash, bi-level, etc. It was the epitome of simple, when luxury meant convenient and not having to deal with 9 million settings and menus (I miss that). My friend’s mom believed in a closed window policy, and the Comfortron and our lungs had to cope with the secondhand smoke. At least we were cool in the summer and warm in the winter.
Jumping ahead a few decades, my 1987 Mercury Grand Marquis LS had ATC. The car was a few years old when I bought it, low mileage, well cared for. Everything worked except the ATC. Maybe it worked and was just crappy. I was used to manual controls, and the panel didn’t look much different from Ford’s manual control cars, so I used it manually my entire ownership.
My next car, purchased new, was a 1995 Chrysler Concorde with ATC, and contrary to what you might expect in a Chrysler, it was FANTASTIC the entire 10 years I owned the car. I would almost swear I set it once, and let it do its thing. Just really damn good.
I’ve mostly had ATC since and miss it in the few exceptions. Driving my winter beater 2005 Ford Freestyle today, it was all auto all the time, and working fine. In my F-150 I occasionally call up the manual modes when Midwest weather extremes call for extreme measures, but mostly revert to automatic when things settle down.
We have two Fusions with ATC, the 2016 works great. The 2018 seems a bit off at times, and I’m going to watch it close as our warranty winds down. If I have it serviced, it will be the first time I’ve ever actually pursued service on an automatic temperature control system.
I’ve never had a car with “manual” climate control, and nor have my parents since perhaps the mid 90’s (my mother’s Civic Si hatch probably being the last one, since I assume it did not have an automatic function.) It’s something I generally don’t touch other than to adjust the temperature sometimes or of course turn on defrost. I have never manually switched the air conditioning off, and in our Audis we leave the recirc set to auto. I do remember our Acura TL Type S had a sun sensor that would adjust the climate control accordingly. I find that with our Audis, the heater is excellent, to the point that I do occasionally adjust the temperature. Overall, though, I leave it set to between 20 and 22 degrees, usually at 21.0 degrees, and otherwise 20.5 in the summer. It is also fun to annoy my father by changing all of the 4 climate zones in his A7 to be .5 of a degree different when I drive it. I can’t see myself living without automatic climate control.
For the record, we leave our heated mirrors on 365 days a year, only switching them off if we select our mirror tilt-down function. (Which requires moving the switch to the desired mirror position in the A7 or the right mirror in the allroad.)
Our ’03 Civic Hybrid had auto climate control. I always had to keep overriding the fan speed, because it would slow itself down too much when the set temperature was reached. We both wanted more airflow. Our ’09 Camry Hybrid also has auto climate control. Again, I have to keep overriding things. No, I don’t want bi-level. No, I don’t want it on recirc. No, it’s 65 degrees outside. I don’t want the A/C on, I just want fresh air. No, I need it in defog mode (which runs the compressor). When spring arrives and I mostly need cooling, it’s quite a bit better, except that, again, when the set temperature is reached, the fan doesn’t move enough air and I have to override fan speed. And, of course, press “Recirc” when I’m stuck behind a diesel or someone in an adjacent car is smoking with the windows open. In the end, I’m just not sure that automating the HVAC controls gains much. The tried-and-true three knobs for fan, temp, and mode do a really good job.
I love ATC but it does not take into account rain, mist, extreme sun, light snow, slush, cloudiness, wet carpets,etc. I find I usually run mine on semi auto. For example, with sun and semi slushy roads, in auto mode, the defrost is adding heat to your windshield drying all the salt onto your windshield. If you manually redirect that heat that doesn’t happen.
My wife hates it in her Fiat Panda, and never uses it, I always have it on in the Tesla Model S I drive for work and love it. First Climate Control I had in a car was in a 1974 Caprice Classic, somewhere around 1987! can’t remember how well that did work.
Best ATC I ever had was my 1st gen Sequoia. 2 zones – front and rear – both with full automatic control, plus the ability to control the rear from the front. No drafts either.
The new to me Prius (3rd gen) seems ok, except that it never wants to select the windshield/footwell vent setting in very cold winter weather, choosing footwell only, and leading to fogging windows.
I must confess that I rarely use ATC in my Acura not because it doesn’t work well (it does), but because it somehow just doesn’t seem right to have the compressor running constantly, even in winter. I feel it adds wear to the system and hurts mileage. An archaic belief perhaps, and I’m open to be persuaded otherwise. Are my concerns unfounded?
I agree with you. But occasionally running the AC compressor, even in winter, helps keep the system lubricated to prevent leaks.
Well on most modern cars the compressor will run, as needed, when Def or on some cars Def/Floor if the temp is above ~40. It works to dehumidify the incoming air to clear the windows quicker, and to keep them that way.
My first auto climate control was in my 2005 Mazda 6 company car. Big dials and buttons, easy to use but I never used it on the automatic setting as it kicked the fan onto maximum speed, which was so noisy it drowned out the radio. You’d expect this if the interior was hot after sitting in the sun all day and you chose 18°C, but if the interior was 21° and you chose 21°, the fan would still roar away on full blast. So I operated that system entirely manually.
The most annoying system I’ve used is in our 2006 Peugeot 307. The auto function itself works well, being generally not too noisy, but it has separate temperature controls for the driver and passenger, and no way to sync them…
In complete contradiction, the best system I’ve used is in our other Peugeot, a 2016 508 RXH. Its a four-zone system, and the auto function is so subtle and so refined, you hardly know it’s operating most of the time.
My 2018 Challenger has the auto climate controls and I rarely use any manual settings. I normally leave it at 71 degrees, all year round, with the fan as high as it gets before it gets obnoxious. When there is snow and/or ice, like tonight. I remote started the car, and when I got in, I turned up the temp to 75 degrees on each side, and put the front defroster on, which is unpleasant to me, both for the noise the blower makes, but also because of the hot air that hits my face. While it’s melting the snow/ice, I get out and remove as much as I can stand to remove, and get back in and shut off the front defrost and get moving.
But I occasionally ride fairly long distances with a friend, who has always run his heat up to “cook your legs” level. I had hoped that with his new Sierra 1500, with all the toys, that would at least be backed off a little. Nope. A couple of weeks ago, he picks me up, and it was 25 degrees out, and as soon as I opened the passenger door, the hot air hit me. I didn’t say anything, all it does is get him angry, and complain that his 3 grown sons complain about it when they are with him too. I used to always ask him, “Are you and especially your legs that damn cold?”, which would get him going, but this last time, I kept quiet and took off my coat and gloves. I was still cooking by the time we got to our destination, 45 minutes away, and when I got out of the truck, the wind hit my pants and I realized I was soaking wet with sweat. I had just gotten out of the shower about an hour before he picked me up. I guess I shouldn’t have bothered. When we left to go back to Toledo, I told him, “I got soaked with sweat coming up here, just set the temp and forget about it, please?”. He grumbled about it and set it for (IMHO) a too hot 75. But even that wasn’t enough, about halfway back, he cranked it back up and I cooked again for about 20 minutes or so. If he wasn’t like this his entire life, I’ve known him since he was 6 and I was 5, I would think something is seriously wrong with him. He just never could tolerate cold, but in the summer, he actually has it too cold, so I think it’s some sort of psychological issue.
My only problem with automatic climate control is a strange quirk in my Kia. It absolutely will not turn on the AC compressor unless the temperature is set to the lowest setting. And then when I inevitably start freezing I just manually override it anyway so what’s the point?
Count me as not a fan, I’m more partial to the manual controls in my S2K and Rodeo. Perhaps is because I’m in the mechanical trades, but it always seems I want something an automatic system can’t give me. Try un-tempered 100% outside air when is cooler outside – no AC compressor, no heat, low fan speed. I figure our homes have thermostats so we don’t have to get up and make adjustments (though seems I still do). How hard is it to nudge the temperature slider or fan speed switch back and forth?