does anyone knows when the A/C is on or not?? is there any way to figure out, other than feeling it by a little loss of power, if the A/C is working...I know a couple of cars wich A/C is working on the defrost mode but...how can I know from wich degree my A/C is starting to work..??

 

Not sure, but room temperature is 68 to 72 fahrenheit. So, I suspect the a/c starts to work below 68.

 

to prevent start another threat....if my A/C isn't blowing THAT COLD...but still blow cold but i mean come on 65 (my minium) is should be freezing in my car after a while but it itsn't. i've sit down in cars where on 65 i have to tell the driver to slow the fan or rise the temp cuz i am freezing...not mine i give you that much.

what could be the cause?

 

Have you recharged your system recently?

 

i thought the a/c was running when it was turned on...
my a/c seemed mediocre as well. Like in my friends ACCORD it gets real cold, and in other cars i ride in often. I thought maybe my freeon was leaking but my mechanic saw no leak, he told me to turn on the "Recirculation" button right when i turn the a/c on and put it on 65. It honestly does work, although i think its probably working my a/c kinda hard. It gets really cold though. I still cant stand knowing why it was basically only blowing hot air at me when i had it on 65 a couple months ago..

 

I didn't realize you were from Quebec, jp. So 68 fahrenheit = 20 Celsius. I believe the lowest I can turn my air conditoner down to is 18 Celsius, which is 65 fahrenheit or thereabouts. At that temperature my car is cold, granted we aren't into summer yet. I did recharge the system going on 2 years ago because the gas disappeared. Given your car is a 99, I wouldn't have expected that to happen yet, but **** happens.

 

sorry if this is a stupid question
waht is recharging your system, how do i do it, what does it do, how much does it cost.

 

Freeon used to be the commonly used vehicle refrigerant for a/c systems, but is no longer used for environmental reasons. 4th & 5th Gen Maximas, according to my Haynes manual, use environmentally friendly R-134a. Section 3-12 details how to check the a/c system and add refrigerant.

Given the questions you are asking, I suggest you not attempt to replace the R134a yourself if you need a system recharging.

My system stopped blowing cold air on a hot day during a road trip in July 2003.

I went into a shop and paid Cdn$134, or about US$105 at today's exchange rates, to test the system, check for leaks and recharge the system with R-134a. This might have been on the high side but I was in no postion to shop around.

My understanding is that the R134a molecules are quite small and the gas will not remain in the a/c system forever.

The Haynes manual recommends running the a/c system for at least 10 minutes once a month, particularly in the winter, to keep the seals in the system lubricated. However, the defrost system uses the same compressor. I may have been guilty of not using my a/c system often enough, but I am from a wet climate and do use my defroster so I don't think that was the reason for the R134a escaping.

I'm not sure what other .orgers incidence is of having to replace the R134a after 8 or 9 years or so, but I'd be interested in hearing.

 

makes sense ^
and yeah i know its r-134a.

 

thanks for the conversion !! but the only goal when I started that tread is to know if I'm running with A/C on or not....only to figure out if my drop of power is reliable to it or either on my coilpacks or ??that's why I'm asking...also, am I running always on A/C so, it will explain the fuel consumption and everything else...

thanks!

 

to get my AC to work i have to set it to auto, and to the lowest temp setting. or else it blows hot air. it takes a minute to start working. also another org guy helped me out by telling me to turn it on and let it warm up, then with the fans on full blast you go under your hood and touch one of the metal hose and if its cool feeling and not wet then your ac is fine. if its warm then your part is burned out. also if its wet then youve got a symptom but i forget what the problem is now. do all of this when the engine is warmed up and running. it should have a small green cap with the letter L on it, iirc. it runs to the left and up.
with all of this turned on your RPM should raise a few hundered to compensate for the juice bieng drawn. if your RPM doesnt raise when you hit the auto button then maybe you can go from there

 

ok I think that's my bad....let's start again figuring out that I'm trying to explain myself the best way I can without forgetting that I'm not biligual and my first language is french....basically, when your driving with A/C on, it will cost more fuel and grab more horsepower...right? the only thing I wanted to know is from wich point myA/C turns on...cause I don't want to keep it work when I don't need it....to prevent bigger fuel consumption and to keep my engine pulling hard...and I was only wondering HOW can I know it either than with the idle speed or with the noise that it makes....my girlfriend have a prelude 97 and a light tells her when the A/C is on...I know that my A/C is working well...but in the "grey zone", I was asking WHEN it's starting to work....anywway, thanks guys for giving me answers!!

 

if you have the climate control, try setting it to "auto" first, it should be very cold in a matter of minutes.

 

I suspect you will find that your air conditioner is working when you set it below 20 Celsius. I have only 4 settings below 20: 19.5, 19.0 18.5 and 18.0. Try setting it at 19.5 and see what happens. I don't think its on at 20 as that is at the low end of room temperature, which as I said starts at 68 fahrenheit or 20 Celsius.

 

I have the stupid automatic climate control in my Maxima too. I hate it! I wish there was just a button to turn on the A/C or at least a light indicating that its on. I find my climate control is different temperatures different parts of the day. In the morning 23 is warm, while in the afternoon it is freezing! I'd prefer an HVAC system that doesn't have a mind of its own. I do find that under 20 degrees is the coolest, so I'd also assume thats when the A/C kicks in.

 

that's what I'm talking about!!! stupid thing that we can't control!...thanks for everyone for helping, especially RMURDOCH for the stats!!

thanks!

J-P

 

Look at your rpm's when you hit the a/c button. It will move if the compressor is working and you will also be able to hear it.

 

The problem with the automatic climate control is that there is no button to turn on the A/C. I don't even have a light to indicate that it's on. I don't know why they designed it like that cause it doesn't make any sense.

 

The best thing to do is when you want it cold, yet preventing the a/c to turn on is simply hit the "econ" button and go to the lowest setting (18 c)

 

There is a button. If it's on AUTO your A/C is on. Regardless of the temperature. The AC and Heater regulate the temperature to whatever you set.

If it's on ECON the AC is off. It will blow heated or outside-temperature air without cooling it.

If you put on the front defogger, the AC is on. To remove moisture.

An alternative to using the front defogger is to set it on ECON and the Floor/Defog setting and putting the temp on 85. The heat will make the water evaporate.

 

I really hate automatic climate control...it's too complicated! I'll try the ECON setting tonight though. I think its always been on AUTO.

 

AUTO means the compressor is running. The maxima compressor is different from many others, because it always spins, but the amount of work it does depends on how much cooling it needs to do. So if you climb in your vehicle and its 65 degrees out and you set AUTO, it's going to be spinning, but hardly doing any work, and not costing you much. Still, at this point I would still choose ECON because then it's not spinning, and it's costing me nothing.

Same thing at 90 degrees. It's spinning, but the pressure differential across the swash plate means that it's moving a lot more R134a around, doing a lot more work to keep your car cool, and eating into your fuel economy more. In normal operation, the max compressor does not stop cycle on and off like Ford, GM, and most others.

So to answer your question, if you don't want it running, pick ECON.

 

Davey that makes sense but in my experience it is not accurate. I would like to know your source on this. Maybe I am misled.

My understanding is that when you set your CC on AUTO, it is constantly running full AC. You could set it to 65 or 79 and the AC will still be working full blast.

The change in temperature is achieved by a door that adjusts cold (AC) air blending with heated air from the heater core. Another sensor measures the temperature of the air coming out and the temperature of the air in the cabin and adjusts accordingly.

For example, if its 90 degrees in the cabin, and you choose 68, the air will come out full AC (no heat) until it gets close to 68 and then the air will be part heat and full AC to maintain the temperature.

 

Now that we're talking about A/C...I was wondering...Does the compressor always turn on when you specify a relatively cool temperature on the Auto Climate Control? Like will it know the ambient temperature is cool and just draw air from outside? Or for that I should just stick with the ECON mode?

 

But when setting it on ECON mode, we're not able to select the wanted draft (to the feet or the body or the defrost) without having it changing by itself....you can select the ECON mode but cannot decide where your air is going...anyway, auto climate control sucks!

 

Auto mode will almost always turn on the A/C compressor above 37 degrees F outside temperature.

Eco mode will not use the A/C compressor but once you manually override it, the Auto mode will start again.

To turn on the HVAC but not use the A/C compressor and being able to manually adjust your own settings, turn on the HVAC by using the +/- button that controls the the fan speed. This puts the HVAC effectively in manual mode without the use of the A/C compressor.

Yes I agree, it is a difficult system. Nissan should have used an A/C on/off botton like other mfg.

 

i have a question about having AUTO climate control set to AUTO...
at idle [650] set it to AUTO and it raises the idle by a few hundered or whatever noticably lets say 800...but if youre driving at any RPM above 800, with it set to AUTO, and turn AUTO off, your RPMs dont drop, if you do the math, it should drop from whatever you're RPM is at by whatever it was raised by, to become normal again....anybody follow?
isnt the rule, A/C and the AUTO setting uses more gas? ..so am i realy using more gas while im driving?
past a certain RPM the climate settings dont seem to make a diffrence. i tried this a bunch of times. drive at 2k RPM and set it to cruise, while the RPM is steady i turn the AUTO setting off and no RPM drop, set it on and no RPMs go up.
i dont use the AC too much even when its realy hot because i dont want to use gas, but it doesnt seem like Im using more gas

 

I think we are beating this topic to death.

Anytime your AC is on (AUTO) there is more resistance on your motor because you are essentially powering an extra high pressure pump using your engine. Which means that the fuel needed to maintain a certain arbitrary RPM (say 1500) will be greater than if the resistance on your motor is lower with the AC off.

Moral of the story. AUTO = AC on. ECON = AC off. DEFOG= AC on too.

You can use the AC and actually save gas depending on what speed you are driving. In stop and go traffic you will lose economy. Open the windows. On highway speeds, the resistance from opening your windows would be a greater fuel loss than closing your windows and running the AC.

 

Um...I know I'm making things more complicated here, but just for kicks...what about manual mode??? I set it to ECON tonight and my fan turned itself up full blast, which I didn't want. I turned it down, then it went to manual mode. I guess this is what I usually have it on. The A/C wasn't on though cause the air wasn't cool enough.

My next car will just have a dial for temperature (red - hot, blue - cool) one for fan speed, and a little button for A/C! I don't know what temp. I want it to be in the car, I just go by how the air blowing out feels, which always seems to be different with this system! Maybe I should have bought a GXE...this thing is posessed.

Good info you guys though! You really understand this system a lot more than I do!!!

 

what i want to know is, if i charge my system w/ off counter stuffs, do i have to worry bout OILS and REFRIG ratios?

i have a 97 and wanna buy a recharge kit. but im not sure if i just charge OILs, just r134 or the ones that have BOTH OILS and r134 in same can, although the latter are for systems CONVERTING from r12 to r134.

well thanks.

 

Yes, the metal hose in my Max. gets VERY cold and wet... so what does that mean? BTW, it seems to work just fine (100K miles)...

 

I don't know what you mean here. In my car, auto= ac on, econ= ac off always. If I manually adjust fan speed or where the air is coming out, it does not chang whether it is in auto or econ.

 

This is because the max has a variable displacement unit, unlike many domestic vehicles. The amount of sweep of each piston stroke alters so that it is pumping more or less refrigerant depending on its needs.

It could not run on full blast all the time because your evaporator would freeze up. Units that do run on full blast have to cycle on and off, and you will notice that the max compressor doesn't do that. Consult specifications on the Calsonic CWV618 for confirmation.

You're right that there can be cold/warm air blending, but only when the temperature in the cabin is very close to the setpoint that you've chosen.

 

Yours is working fine. If it's wet, it's cold enough to condense water vapour from the air, and is a good sign.

 

no one charged b4??

 

Read "How do I top up my a/c?" on this page. Basically it's your call and depends on how much oil you think you may have lost from any leaks.

 

thanks, i could've sworn i checked the how to's and stickys, but thansk again.


so basically wal-mart kits are charging the LOW side? i dont think i have a leak, but im just wanting to charge it up like refill..