2007 Infiniti G35 Sport: Not a Fan of HVAC System

Actually, the fact that the "AC" is on doesn't mean that the air is cold, since people typically defrost their cars with warm air. The above poster is correct about the fact that the AC system removes the moisture from the air, though. I think that the difference Doug is noticing is that most cars use the AC for the defrost setting but do not alert the driver to this fact, so that when the setting is switched to something else, the AC turns off again. In Nissan products, the AC stays on after you select a setting other than defrost (even if it wasn't on before you selected defrost), so you have to manually turn it off if you don't want it on.

Oh that sucks if you have to turn it off when you switch to another mode, but being able to turn it off while in the defrost mode would be a nice tradeoff.
 
I wished that I could just turn the AC off in my old Fit when it was on defrost, but it didn't let you. I live in the Pacific Northwest and with all the rain I always leave my cars on defrost continuously, but having the AC on all the time hurts mileage.
 
I ended up disconnecting a wire in the dash that removed the auto-AC function from the Fit. It was really easy actually and I got about 1-2 MPG better afterward, not to mention slightly better performance. If it really started to fog up I could just turn on the AC myself.

Jeez,I expect a little more knowledge from a writer for a car site.
 
I am pretty sure that all cars activate the A/C compressor when the front defrost mode is on to dry the air.
 
This is probably not so important in the winter when the air tends to be dry anyway. But in rainy conditions it is very useful.

BMWs also turn the A/C on when you hit defrost (like all cars should, as bennetpullen correctly described), but when you hit defrost again it returns you to the exact mode and fan speed you were in previously. But you don't usually have to hit defrost, because the climate control has humidity and windshield fogging sensors so it doesn't let the windows fog in the first place when in Auto mode. Infiniti/Nissan should really get on that. :-)
 
Most cars actually do turn on the A/C when you select defrost, even on fully manual systems like the Fit. The A/C light on the button also needn't be on for the compressor to run.

I'm aware that most cars turn on the A/C when the defrost is on. The point of the blog was about the relative complication/simplicity of the controls.

AC with defrost is invaluable when dealing with snow as the car sucks snow in from under the cowl then it melts and turns into water vapor, fogging up the inside of the car. On vehicles without AC or broken AC, I've had to scrape frost from inside the windshield because of it.

bennetpullen, why couldn't you have left your Fit set on partial defrost? The Fit only turns on the AC automatically when you turn that knob all the way to the right on the Full Defrost setting. On partial defrost you will still get some air blowing from the foot vents and it doesn't turn on the AC compressor. We get a lot of humidity here in the south and that's the method I use.
 
Aslo, I agree that knobs for fan speed are preferrable to buttons. Having a knob to select where the air flow is coming from is also nice. I don't think I even like the look of the Infiniti HVAC controls. They look a bit cheap. I guess the picture doesn't do it justice though.

is it me or does the thing under the passenger temperature knob say compact flare?

It says "Compact Flash." It's for a connection to upload music and other files to the car's hard drive.

WHAT ABOUT THE FIT'S TRANSMISSION PROBLEM?!?

How do you write about cars and not know how an air conditioning compressor works and why it would defrost the windows much quicker?

Geez, lay off the guy already.
My WRX also did the same thing, turning on the A/C compressor when the dial is in the defrost mode. For some reason I hate it and was able to find a relatively simple mod to deactivate it.
Most of the time I can defog my window fine by blowing warm, non-dehumidified air; why waste the extra gas by running the compressor?
Dunno why it offends my sensibilities to have a car manufacturer make the choice for me.

Dilettante is right, it's a Nissan thing. In my Sentra the A/C light does not go on when I select defrost (but I assume it is running). Then when I turn it to heat or whatever the light pops on. I realize I will not actually get cold air as long as the temp dial is in the red but it's a bit annoying in that "Hey, I don't remember switching that on" kind of way. I have touble believing it would have a 1-2 mpg effect, though. The compressor does not run continously unless you are running a/c full blast on a hot day.

As the owner of a 2008 G37 coupe with the same interior and control, let me be the first to tell you that Honda has Nissan beat by a country mile when it comes to ergonomics. I can breeze through the controls in an Acura RL, but the G37's controls are not at all intuitive. The steering wheel controls are not labeled clearly enough, the radio controls appear sneezed on. There is no XM button to be found, even though the car has XM - you must scroll through "modes". Instead, there is a giant AUX button. Seeing as how the G37 has a full ipod interface, this AUX button refers to the system's video capabilities - and how often will that be used? Also the climate control and additional radio control buttons are close together and have identical knobs.
 
In general, the ergonomics in my G37 are poor in comparison with Hondas and Toyotas I have or have had. Nissan needs to give that some work.

It's a change that an old man is not used to.
Old man says "I hate change."
 
Some day, as you are forced, you will get used to it, you will come to know this as the norm.
 
Then some day, a conventional Honda Fit styled control may be presented to your child.
"These controls are terrible!"

Couldn't you find another car to compare the G35 controls with but the Fit? Wow, the Fit still uses sliders (above the HVAC knobs)?! That's so primitive... but than again, this is just a Fit.
Let'see how it's done in the C300, CX9, Enclave and other decent, modern cars you have in your garage.

Wow. I have been reading these long-term entries, but I had to say something about this one. You all are really spoiled by the Southern California weather!

sometimes simpler is better. I put 1,500 miles on a loaner car with the fancy auto air setup and still didn't get used to it. Aside from having it automatically turn the compressor on and off when the temperature gets cold enough I didn't like it. I too like the nice easy to use knobs. One quick twist and the fan is on high rather than having to hit a button several times or switch off some other mode before it will let you pick the speed.
It's funny how in an attempt to improve things they make it so it takes more button pushing to accomplish the same task. On the infinity how do you tell it where you want the air to go? Somehow with the 'mode' button?
Years ago I had a rental car that had stops between the selections on where to send the air and it would split more to the floor or dash depending on where you stopped. That was kinda slick.

Seriously, someone described the rain around here as a "huge thunderstorm" or something to that effect...but we haven't even gotten steady rain. Anybody from the South (Florida flash storm, anyone?) would laugh at what we got. And here it's genuinely "inclement weather" where the freeways all slow to 40mph even first thing in the morning. Hilarious. Rain here really is like snow elsewhere.

The controls aren't complicated. When you hit defrost on an automatic climate control system, the goal is the clear the windshield as fast as possible. The fan speed increases to max speed to help in the process. The A/C will ALWAYS run on most of these systems even if you hit the button to switch it off. In fact, a lot of cars will run the A/C in floor mode with the heater on. That's the "automatic" part of the climate control system- if you use it to your advantage, it'll work.

Kevlang is right. It sure is taking a long time to change the dirty transmission fluid in the Fit...What's the status?

The Fit is the only current Honda that DOESN'T use the exact same system as Infiniti. Civic, Accord etc. will all turn on the compressor with the defrost button. And the '09 Fit will probably go that way.
 
I have to say that unless you live in a desert (Calif.) with perpetually dry air, the defoggers work 10x better with the compressor on. For most people this is a much better solution. Dry cold air will defog much better than warm moist air.

Since this HVAC thing appears to have been beaten to death, I'll comment on the clock. It looks like a wristwatch, doesn't it? The radio controls are all on the wristband part of it. Nifty.

Doug, you should spend a winter in New England (you'll use the defrost everyday)
 
Defroster's generally use AC because it is trying to condition the air to have a lower relative humidity. If you are blowing air with a Dew Point of 70°F (pretty humid air) onto a windshield that is at 60°F, then you will get condensation and fog inside. Conditioning the air can bring that Dew Point of that air down to 50°F and you get a clear windshield.

Langjie: Thank you so much. As much as I appreciate being harangued for not happening to know why the A/C goes on (by chrishs and others)--and actually, I asked my executive editor and he gave me a great explanation -- I really appreciate your taking the time to explain it. Very kind of you. From what I gather, it is now standard operating procedure for the A/C to go on automatically with the defrost. Thanks for taking the high road.

Doug, by the way. The purpose of the AC compressor coming on when defrosting is...HA! HAA!!!
 
I couldn't help it. This blog post has been hilarious. You da man though. Go drive that 308 and forget this pedantic preaching.

It's funny because I explained this to my girlfriends little sister a day after I posted this.

jsc--
 
It says "Compact Flash" for a flash drive for the radio/navigation.

The goal of a defroster is to remove moisture from the window surface, right? Well, the A/C compressor removes moisture from the air, thus more quickly defogging the window. SOme people seem to be under the impression that running the A/C means the air has to be cold. Untrue. You can run full heat with the A/C on (and this is actually the fastest way to defog a window)......

"The Fit is the only current Honda that DOESN'T use the exact same system as Infiniti. Civic, Accord etc. will all turn on the compressor with the defrost button. And the '09 Fit will probably go that way."
 
Incorrect, even the lowly Fit automatically turns on the A/C when defrost is selected.