Ventilation problem

[larrys3255]

Wow! I opened a hornet's nest here.

Perhaps I did not understand some of the comments, but I still find that it is impossible to use "Mode" to change the air to the windshield and maintain recirculation mode. The minute you do that it changes to fresh air mode. There is no way I can figure out how to achieve recirculation and have the air go out the windshield exit. This means that whenever the windshield fogs, I must endure breathing truck fumes to remove the fogging. Not good at all. Why don't they just modify the software so that it is possible to use recirculation and yet remove fogging. This is not nuclear science.

Larry

 

[aqn]

... How did you figure out that "other components [...] are still being handling [sic] automatically" when the "AUTO" light is off? ...

If you start playing with the temp buttons it becomes obvious fairly quickly. The fan changes speeds and the AC gets colder if you turn the temp down.

Here's what I observed.

Ambient temperature is 83.
Temperature is at 70.
Fan on, at lowest speed.
All climate control lights are off except for ventilation control, which is on "outside air".

I hit AUTO. A/C comes on, ventilation control switches to "recirculation", fan starts speeding up. As expected.

Now I lower the fan speed one notch, thereby the AUTO light goes out. A/C light & recirculation is still on.
I lower fan speed to lowest setting: nothing else changes.
I turn off the A/C: ventilation control switches to "outside air". (But it won't on subsequent on/off of the A/C. That's a different matter.)

Now my expectation, if AUTO mode is still operational, is that if I lower the temperature all the way down to 60, I would expect the A/C to come back on and the fan speed to increase: that does not happen.

No matter what I do, the fan speed will not increase on lowering of the temperature when AUTO is off. In fact, when AUTO is off and I make a change (fan speed, ventilation control, A/C etc.), there is no side effect. The only thing that has a side effect is when I raise the temperature setting all the way up to something like ambient temperature + 10, then the climate control energy consumption reading starts to increase as the heater starts coming on.

 

[aqn]

Wow! I opened a hornet's nest here.

The LEAF's climate control is the gift that keeps on giving!

 

[highcountryrider]

Ain't that the truth! :roll:

 

[davewill]

...Now I lower the fan speed one notch, thereby the AUTO light goes out. A/C light & recirculation is still on....

As soon as you touch the fan speed buttons, the car stops controlling the fan. The scenario above had the user pressing the fresh/recirc button, and having the AUTO light go out. In that case, the car keeps controlling fan speed.

 

[muus]

My Mazda 5 works in the same way. I press the auto button and the car decides where to direct the air, fan speed, recirculation, and A/C. It can be 50 outside and the car turns on the A/C (to remove humidity). I hit the A/C button (to turn it off) and the rest of the system continues the be under automatic control. As the outside temperature changes or if I change the desired temperature, all other system settings can and will be modified in order to try to maintain the desired temperature, only the A/C won't turn back on. If you change the fan speed, the fan speed now becomes fixed and only the other settings can be automatically regulated. In order to re-enable the fully automated function you simply press the auto button. From what Leaf owner are saying, the system is working properly, only a HEAT button is missing (to disable the power hungry heater).

 

[aqn]

...Now I lower the fan speed one notch, thereby the AUTO light goes out. A/C light & recirculation is still on....

As soon as you touch the fan speed buttons, the car stops controlling the fan. The scenario above had the user pressing the fresh/recirc button, and having the AUTO light go out. In that case, the car keeps controlling fan speed.

If I change the ventilation setting (fresh/recirc), AUTO goes off. And if I don't touch anything else, nothing else changes. At least, not during the ten minutes waited. However.

If I lower the temperature when AUTO if off, then the fan speed increases, to increase the cooling rate. That's the same behavior as when I increase the temperature: the heater comes on, and maybe the fan speed increases. I suppose one could consider that "AUTO". I don't, since the owner's manual claims that in "AUTO" mode, "the system automatically controls constant temperature, air flow distribution and fan speed." (page 4-4).

 

[davewill]

If I lower the temperature when AUTO if off, then the fan speed increases, to increase the cooling rate. That's the same behavior as when I increase the temperature: the heater comes on, and maybe the fan speed increases. I suppose one could consider that "AUTO".

There you go. That's all anyone said.

 

[FairwoodRed]

The part that chaps my hide is the I can hit the "OFF" button to completely kill auto, then use mode, fresh air, and the fan speed buttons to set things the way I like, but the heater will STILL kick in if the temp isn't turned down.

+1 All I want is some air flow and not to have to chase the temp setting to within 3 degrees of outside temps to keep the power hog heater off line. I really want a way to disable the heater.

Back to the original post, I am also frustrated that when set on defrost, I can not change to recirc. I realize that fogging is worse that way, but I really don't want to breathe the polution cloud of that belcher that I'm about to drive thru. Since I have to adjust to this while driving, I need to be able to do this with only ONE button push.

Ugh. Take this high tech climate control away and give me the manual controls from the 80's. Remember how you could slide it partway over for 75% defrost and 25% feet?

 

[planet4ever]

Ugh. Take this high tech climate control away and give me the manual controls from the 80's. Remember how you could slide it partway over for 75% defrost and 25% feet?

Right, I think that the designers sometimes forget that there is another very powerful computer in the car, in addition to the printed circuit ones they sell us. If you give this wireless, silicon-free, computer access to the native climate controls it can do a very nice job of controlling them, all on its own.

Ray

 

[JPWhite]

Nissan has decided that the Leaf driver cannot select "Air Recirculation" while the "Automatic Climate Control" is on but must use the "Fresh Air Intake" mode. This also occurs when you click on the "Front Defroster" button. I guess that some Nissan engineer in his wisdom has decided that it is more efficient to defrost the front windshield using fresh air intake and so has made that the only option for the driver. I don't know about you but I really dislike having to breath car fumes while driving and would gladly endure the somewhat lower efficiency while still benefiting from the Automatic Climate Control system. It seems to me that this is a software issue and could be easily corrected. Are there any other Leaf drivers who feel like I do?

Larry

Yep its one of my pet peeves as well.

In the winter I want the auto mode to vary the fan speed appropriately as the car warms or cools, but I HATE warm air in my face, I prefer it either at my feet or on the windshield. If I change the outlet where the heat comes from it turns off the auto setting meaning the fan will need manual adjustment.

With a car without climate control, this is normal, but hey, if I have climate control I want it to be much smarter than this!! Especially because one can't 'glance' to see the fan speed as with an old fashioned dial. The climate control settings summary is not available on all screens on the display panel, I wish I could lock it so they were.

 

[davewill]

... In the winter I want the auto mode to vary the fan speed appropriately as the car warms or cools, but I HATE warm air in my face, I prefer it either at my feet or on the windshield. If I change the outlet where the heat comes from it turns off the auto setting meaning the fan will need manual adjustment. ...

I think you'll find this is not so, and even though the auto light goes out when you press "mode", the climate control will still control the fan speed.

 

[EricBayArea]

+1 All I want is some air flow and not to have to chase the temp setting to within 3 degrees of outside temps to keep the power hog heater off line. I really want a way to disable the heater.

I totally agree. I just got my car last weekend and driving home, i put fan speed on 1 with outside air, AC off. I realize that since the lowest temp setting while doing this is 60 degrees, if the outside air temp is lower than 60, it will turn the heater on which will suck. Even if it's 55 outside I may still want outside air coming in with fan set to +1.

In another thread for recommendations to Nissan (for an upcoming visit by Nissan), I suggested they add a "Low" to be a temperature below 60, that effectively disables the heater no matter the outside temp. That would be enough for me. Which is what my ICE car has in the temperature dial - there is a 60 degree setting and then one click below just allows ambient.

 

[Levenkay]

This may be stretching the topic too much; apologies in advance if that's the case. There's such a wealth of deep background car knowledge here, though, that I thought I'd ask about what seems to me to be pervasive design misfeature of automobile ventilation systems: the disappearance of flow-through ventilation. From what I remember of cars in my youth, a ventilation fan was an optional device used to provide heater/defroster airflow at low road speeds. At any speed over 30MPH or so, one just opened up the cabin air intake vent to whatever degree desired, and air from the high-pressure area at the front of the car would naturally blast in, flow through the cabin, and out through the rear of the car. The last car I owned that behaved this way was a late-seventies Honda Accord (1978?). It had this a-MAZE-ing bit of Japanese high technology that seems to have eluded the makers of all three ICE cars I've owned since: a hole somewhere in the rear trunk/cargo area for allowing air to escape. Those other three cars have been so tightly sealed up that not only would air refuse to enter the cabin except under the urging of the ventilation fan, but unless a window was cracked down slightly, running the fan while the ventilation system was set for external air intake would overpressurize the cabin to such an extent as to actually force that external/recirculate selector (it was purely mechanical) back to "recirculate". So this would create a delightful vicious circle in the steamy wintertime: Why do you crack the windows? So that you can get defroster airflow. Why do you need so much defroster airflow? To get rid of the excess cabin moisture. Why is there so much cabin moisture? Because the inwardly-slanting window is cracked open, and it's raining outside... Grrr..