Toyota Prius Forum banner
1 - 20 of 33 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter · #1 ·
During cold weather, when I just want warm air coming into the cabin, I use the climate control set on "Auto A/C". I presume this setting does NOT run the A/C compressor as in traditional vehicles.

FWIW, on the display screen under "climate" I don't even see a "heat" or "heater" button.

Clarification would be appreciated!
 

·
Registered
Joined
·
1,560 Posts
Yes it will heat when the outside temp is less than temp setting...not sure how many degrees it takes...

What the car sadly lacks is a "don't screw with the outside air on a cold day" option.
 

·
Registered
Joined
·
219 Posts
Actually for the sake of dehumidification for defrosting, most cars will run the compressor when it's cold outside.

The principle of the Prius's system is set and forget -- it'll take care of using heating and cooling automatically as necessary to give you the temperature and conditions you ask for, while allowing some options for you to override its automatic controls in various ways. There is some disagreement about how smart its automatic controls are, and whether it provides all the overrides it should.
 

·
Premium Member
Joined
·
888 Posts
Yeah, there is plenty of disagreement over how well the system works, however its behavior is no different than any modern auto climate system I have used on other vehicles.

There is no need to cancel the a/c switch on the Air Conditioning screen any time of the year. It truly is a "set it and forget it" system. As for winter use of the compressor, it does use the A/C compressor to dehumidify the cabin, which helps remove fog from the windshield and helps prevent fog up of windows due to exhailations. Just about every modern car activates the a/c compressor during the winter when you are in defrost mode. On top of using the compressor for dehumidifcation, it is also smart to ocassionally run your A/C compressor during the winter to keep the seals and tubing lubricated. This system will run the compressor enough during the winter to acomplish just that.

The effect of A/C on mileage is minimal. Do not avoid using it. In addition to providing interior comfort, the battery basically operates most efficiently when it is at room temperature. That requires that you run the climate control system to a setting that is comfortable to you and you will be providing the same comfort to the battery.
 

·
Registered
Joined
·
47 Posts
HunterGreen said:
The principle of the Prius's system is set and forget -- it'll take care of using heating and cooling automatically.
Maybe so, but at the very least there are user interface "opportunities" here.

Say it is set on automatic at 70 degrees. Outside it is 54 degrees. So the unit should be heating the interior. Check the climate screen and you see auto is on, and AC is active. No mention of heat, so the natural conclusion is that it is cooling instead of heating - not what you expect to see. Tempting to manually override and turn the AC off, also not what you want for later when the outside temperature rises to 78 degrees, etc. etc.

Perhaps the simplest solution is to change the AC lable to AC/Heat.

That said, it seems to work pretty well if you set and forget. Just ignore what you see on the screen.
 

·
Registered
Joined
·
2,285 Posts
The yellow bar above the A/C button on the climate screen does not signify that A/C is being used at that moment. It only means that it is available if needed to maintain temperature.

If you press the button to remove the yellow bar, then the system will not use the compressor under any conditions.
 

·
Registered
Joined
·
2,243 Posts
Like Rich said, "Set it and forget it." Mine has been in Auto A/C since I got my car in 2004. I adjust the temperature up or down a couple of degrees when necessary. It works great!
 

·
Registered
Joined
·
7,161 Posts
I sometimes override system settings, such as when the air outdoors is cool and somewhat dry, I'll turn off the AC and set it to fresh air. Otherwise, it may run the compressor when initially the cabin temp is higher than setpoint due to solar warming. Down here, even in winter it is a factor.
 

·
Registered
Joined
·
257 Posts
Rich_in_Tampa said:
The principle of the Prius's system is set and forget -- it'll take care of using heating and cooling automatically.
Maybe so, but at the very least there are user interface "opportunities" here.

Say it is set on automatic at 70 degrees. Outside it is 54 degrees. So the unit should be heating the interior. Check the climate screen and you see auto is on, and AC is active. No mention of heat, so the natural conclusion is that it is cooling instead of heating - not what you expect to see. Tempting to manually override and turn the AC off, also not what you want for later when the outside temperature rises to 78 degrees, etc. etc.

Perhaps the simplest solution is to change the AC lable to AC/Heat.

That said, it seems to work pretty well if you set and forget. Just ignore what you see on the screen.
What most forget is that AC or A/C stands for "Air CONDITIONING" not "Air Cooling"
 

·
Registered
Joined
·
47 Posts
KTPhil said:
The yellow bar above the A/C button on the climate screen does not signify that A/C is being used at that moment. It only means that it is available if needed to maintain temperature.
Yes, that is apparently what we sorted out, but it sure seems like a botched little bit of interface design -- virtually everywhere else in the human interface of the Prius and other vehicles, (fan speeds, transaxel mode, audio preselects, etc.), lit means on. Should one expect drivers to instinctively know that in the unique case of A/C, lit now means "available if needed?" I'd prefer two small indicators: Heat and A/C, lit when active, off when not.

Anyhow, no big deal, just an interesting example of how the small interface stuff really affects the user experience when it comes to devices - computers, operating systems, vehicles, GPS's, etc. It's not just fluff if users are confused and thus don't operate the thing as intended.

My observation is that Toyota generally does a pretty good job of such things, including most of the Prius design. This small example aside, I find it a very intuitive and comfortable cockpit.

Of course, the first time I test-drove one, I told the salesman I thought the shifter wasn't working because it wouldn't "stick" in the forward or reverse position - just kept on springing back to the home slot.
 

·
Registered
Joined
·
2,285 Posts
The yellow A/C button indicator is not unusual. For years, foriegn cars have used a separate A/C button, and in all cars I have seen it includes a lamp which lights. Exactly as in the prius, it signified that the A/C MIGHT run at any time, depending on temperature. This is true of both climate control and hotter/colder analog systems. A normal compressor will cycle on and off without changing the lamp status; the Prius' is electric, but works the same.
 

·
Registered
Joined
·
7,161 Posts
Exactly! In ANY car, ON does not mean RUNNING. You can hear the compressor cycle off and on, especially on idle as the engine's idle speed shifts with the compressor engagement.

To top things off, the Prius compressor is variable speed. Do we need a manual control for that too?
 

·
Registered
Joined
·
47 Posts
Well, not to beat a dead horse, but...

I do understand the usage of the indicators and arguments about the compressor being "available" versus "on." I fully appreciate that the system works pretty well. Well-explained by all.

In a nutshell, it all makes sense if you know that "air conditioning" is different from "air cooling" and a lit indicator lamp means the system is "available," rather than "on" and active - at least for his item.

Judging from the 30+ posts on this topic here and over in Priuschat (this population plausibly being even more technosavvy than average), the current lexicon may be "correct" but isn't doing its job well, i.e. it is confusing folks a bit more than it needs to.

Maybe call it "climate control" - that way a driver looking to see if the "heater" is working will get more clues than the fact that the "A/C" is "available." Just my $.02.
 

·
Registered
Joined
·
2,348 Posts
I agree that "auto climate" would be more helpful and less confusing. I've been a great fan (no pun intended) of leaving Auto A/C on and just adjusting temp as needed. I will at times use manual overide to direct the vents to splitting with the defrost if I'm getting some fogging. I don't like the actual defroster as it blows too hard and noisy so I turn it off as soon as it's been effective.
 

·
Registered
Joined
·
2,285 Posts
I use it on manual almost all the time. It's peculiar to my mild climate, but the auto setting is rarely right for me.

I don't like a draft blowing on my face, so I turn the vents up. The car will be cooled/heated, but I don't get a blast in my face.

The problem is, the AUTO setting runs the fan much too slowly for this to remain comfortable. I've tried, and in summer I have to set the temp about 6-8 degrees colder in AUTO than in manual mode (warmer setting, higher manual fan speed). Because of this, the coimpressor runs less on manual than AUTO, saving wear and gas.

On mild days (cool evenings on a warm day), I dont' need A/C at all. It's too noisy to leave the windows open, but the outside air temp is fine for me. So I manually set the fan at midspeed, no recirc, no A/C, and the temp all the way to max cold. This is basically creating a "silent vent wing" effect. Again, less wear and less gas.

This means I am running the blower more, perhaps wearing it out sooner. But a blower will be far cheaper to replace than an A/C compressor! I also like the fresh outside air (filtered, of course).

So, other than defog/defrost operations, I leave iton manual (mid fan, no A/C, no recirc), and set the temp as needed.
 

·
Registered
Joined
·
457 Posts
Running the Prius heater manually is no big deal; (A/C off if you wish.) You just tap a few buttons suitable for the weather at start up and then adjust the temp as needed from the steeing wheel. I prefer it that way. It gives me something to do.
 

·
Registered
Joined
·
39 Posts
Hi All,

I took delivery of a 2006 Pkg 1 on Wednesday in Wisconsin, 284 miles from home. YEH! :)

I was also confused by the Climate Controls terminology. Here is my suggestion for what it should be like based on what people are saying its doing on this thread.

Relabel the A/C button to ATC (which stands for Automatic Temperature Control). So the yellow bar in that button would indicate the ATC is enabled. On the left side of the ATC button have a red bar graph which indicates relative heating and on the right a blue bar graph which indicates relative cooling. Then when people are using the system for temperature modification and/or window defrosting what the system is doing, and how the vehicle is using energy, and might respond in traffic would be perfectly clear.

There should also be a button to select air drying source. Which should toggle between external air (automatically switch reciculate on and off as air humidity requires) or A/C compressor drying. In mid-winter weather one can easily dry out cabin air with outdoor air, but in the spring and fall, in a foggy and misting rain just above between 32 and 45 F, one really does need that A/C compressor to keep the windows clear (turning recirculate off can actually make the windows foggier on those occaisions!).

Another thing that confused me was the "AUTO" button, which apparently automatically sets the fan speed. Initially I thought this was the ATC button. But, instead the A/C button was the ATC button. Did not have to use the defrost at all, just turned the recirculate off and on.


As a side note - the car did 42.7 MPG on the trip home with the cabin set to 72 F and the outdoor temps between 15 and 32 degrees cruising at 70 MPH for 3/4 s of the trip then 65 while running into some buffeting head winds on the final leg into Chicagoland. So, I am pleased. Cannot wait till summer, when the tires are broken in, and I get the break-in oil out of it. 50 MPG here I come !
 

·
Registered
Joined
·
457 Posts
"Relabel the A/C button.etc.etc.."
**********
But.. since this ain't gonna happen - just learn the existing system and it's various "buttons." It gets easier as you go along. I agree that they may have over-engineered the current layout but it's what we have.
Some of the old analog twist knobs and levers were pretty efficient and could be set without looking. I like fat toggle switches in an airplane (as opposed to push for on/off) so you can FEEL it without looking and.. they make a nice click sound. All in all, the Prius climate control works pretty well. Using the Auto mode full time will keep things comfy most of the time. I do like the ability to fine tune the cabin temp from the steering wheel. Just memorize what button it is coz you (I) can't see it at night.
 

·
Registered
Joined
·
4,873 Posts
The Chinese have got it right in their new "Gilly" soon to be sold here by Japanese and Korean dealers. First knob on the left turns system on and then continues turning for volumn of airflow. Second knob rotates for temp, and a sliding bar selects where airflow will be directed. Does that sound at all familiar? Like something in all cars 25 yrs ago!
From pictures of the dash, it looks like this system is in the new Toyota "F. J. Cruiser."
 

·
Registered
Joined
·
7,161 Posts
Donee, you have it backwards. Auto is just that: auto everything. AC, heat, fan speed and airduct are chosen automatically. The AC button on the screen enables or disables the AC compressor, nothing more. It doesn't mean the compressor will actually run. That depends on the Auto and the temperature setting, and how hot/humid it is in the cabin.

Now you can override some things, such as AC compressor, and still maintain Auto. Change the fan speed however, and you lose auto. Basically all you really lost was fan, recirc, and air duct auto functions. The car will still use heat/AC to regulate temp and humidity.
 
1 - 20 of 33 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top