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aircon set to AUTO


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i have used the Auto setting on the aircon a couple of times

and when enabled first thing in the morning it blasts me in the

face with freezing cold air is this normal, if it is what are the pro's for 

using Auto over manual settings.

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I have mine on Auto permanently, with the a/c enabled. On very cold mornings it might take a short while before the fan ramps up and heat comes through but it never blasts cold air, except as said above, when using the demist function.

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21 minutes ago, NemesisUK said:

I have mine on Auto permanently, with the a/c enabled. On very cold mornings it might take a short while before the fan ramps up and heat comes through but it never blasts cold air, except as said above, when using the demist function.

I used to have AC on permanently until a mechanic advised that it causes unnecessary wear on the AC compressor. Premature failure possible.

Unsure if that's true but to be safe, I no longer leave it on all of the time.

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Just now, ikeja said:

Auto on permanently also AC as this avoids the seals drying out.

Exactly this ^^^^

27 minutes ago, matt8 said:

I used to have AC on permanently until a mechanic advised that it causes unnecessary wear on the AC compressor. Premature failure possible.

Unsure if that's true but to be safe, I no longer leave it on all of the time.

What is "unnecessary wear"? I my opinion it is "necessary" to operate the a/c all the time to keep the cabin dehumidified, the windows mist free and most importantly, me comfortable!

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30 minutes ago, matt8 said:

it causes unnecessary wear on the AC compressor. Premature failure possible.

As NemesisUK has said, the compressor doesn't run when it's unnecessary - only when it's necessary, to keep the cabin comfortable and the windows clear. Having said that my experience of fridge compressors is that they run forever. One fridge I know has been running without problem for 34 years. 

However, the air conditioning in cars has extra problems compared with a static fridge. In particular the seals drying out and loss of gas. Running the air conditioning at least once a week helps to prevent that. I had a car once whose air conditioning needed no gas topup for 11 years and that was with the air conditioning always on. Its compressor never had any problems.

On conventional cars the clutch on the belt-driven compressor can seize. I imagine not using the air conditioning could cause this to  happen prematurely. But the IS300h compressor has a 230v electric motor instead of being belt driven and electric motors tend to go on forever.

So I keep my air conditioning on all the time. 

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14 hours ago, 200h said:

i have used the Auto setting on the aircon a couple of times

and when enabled first thing in the morning it blasts me in the

face with freezing cold air is this normal

Going back to the original question! Just wondering if the Auto button was the last button you pressed. If you manually adjust the fan speed after pressing Auto, the fan will no longer be controlled automatically, even if the Auto light stays on. But if the Auto button is the last one to be pressed the fan will speed up and slow down automatically.

Having said that, I think I do get some cold air from the vents when first starting in the cold weather. I wouldn't describe it as a "blast" but for a short time it might be colder than I'd like. But within about a minute, it's no longer very cold. Obviously this cold air is coming from outside, or maybe even from the coldness of the system internally at first. Might be better if the software decreed that there was no air at all until the system had warmed. But the tubes will still be cold until you force some warm air through them. So it's probably a balancing act of having no air at all for a few minutes or start warming up the tubes as quickly as possible. It must be a dilemma for the software designer. Maybe someone else knows more about the intricacies of how the software controls the Auto climate system on startup.

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14 hours ago, 200h said:

i have used the Auto setting on the aircon a couple of times

and when enabled first thing in the morning it blasts me in the

face with freezing cold air is this normal, if it is what are the pro's for 

using Auto over manual settings.

First thing, when cold...

I set my heat/direction etc...

If needed, I then use the 'clear that screen now' button.

It does blast me as it's pushed out at high speed - that's fine and expected.

When clear, I press that button again, and it's job done.

 

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Pretty sure I've told this one before but I remember this subject being discussed years ago on a BMW forum.

After much too-ing and fro-ing about fuel consumption, fan speeds, wear on components blah blah it was generally agreed that the correct operation for climate control is...

  1. Buy car
  2. Set climate control
  3. Some years later, sell car

 

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4 hours ago, Thackeray said:

Going back to the original question! Just wondering if the Auto button was the last button you pressed.

i have the ventilation set to floor and face and speed at 3 or 4

i have then selected the auto mode

next morning at 5.15am i start the car and have an icy blast straight at my face

at that time of morning its horrible and not pleasant..

as i said i have only used this setting a couple of times and now wonder if there

is something i should be doing before selecting auto mode..

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On my GS I set the controls to auto for the direction and the air intake also to auto and temperature to suit i.e. 21.5 and only use the demist front manually when required and have found this setup works well. Don't know how newer models work though.

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3 hours ago, 200h said:

i have the ventilation set to floor and face and speed at 3 or 4

i have then selected the auto mode

next morning at 5.15am i start the car and have an icy blast straight at my face

This is a bit of a mystery. The manual says when you switch to Auto:

"Air outlets and fan speed are automatically adjusted according to the temperature
setting."

So the fan speed and vent directions you set previously should be ignored.

If you've set the intake to outside air. you could try switching it to recirculated air.

As another experiment, when you start the car you could press the Off button for a minute or so while the car warms up and then press the Auto button and see if you still get an icy blast (either on recirculated or outside air.)

I assume you've got the temperature settings at a comfortable number, say, 21 or thereabouts.

If you've still got a problem, maybe there's a fault that you could get rectified under warranty.

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2 hours ago, 200h said:

i dont let the car warm up first

i get in ,start and go and let it warm up whilst on the move.

I didn't mean you should wait while the car warms up. Sorry, I wasn't very clear. I always drive off straightaway - more so in conventional non-hybrid cars as idling cold engines is supposed not to be good for them.. I just meant you could press the climate control Off button initially as you drive off and then press Auto a minute or so later and see if you still get very cold air.

If it was me, I'd want the temperature a bit higher too! Especially as you're finding it too cold.

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In the infotainment settings there is a setting in the Vehicle settings menu to change the aircon/fan between fast/medium/soft and eco on/off. I’ve set mine to soft and eco on. Have you got yours set to Fast by chance??

I also don’t get a cold blast in morning, usually takes about 5 mins before the fan speed increases on auto, as car warms up, temp set to 21-23deg. You can also shutdown the vents independently of the auto setting.

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I checked what happens on my car as I set off this morning. Outside temperature 13C; inside set to 21C. Air conditioning on and air intake set to outside rather than recirculated air.

As I set off with the engine cold there was a trickle of cold air from the central vents - enough that I could feel by putting my hand over the vent but not enough to be felt on my face.

After about three minutes the cold air changed to a trickle of warm air. Again I could feel it if I put my hand over the vent but there wasn't enough force for the air flow to be felt significantly on my face.

After about 15 minutes of driving, the trickle of air stopped completely. I assume this was because the cabin had warmed to the set temperature. 

I expect that if the outside temperature was higher than the setting for the inside, there would be cold air coming from the vents.

9 hours ago, Steve44 said:

there is a setting in the Vehicle settings menu to change the aircon/fan between fast/medium/soft and eco on/off

This sounds like a good thing to check if the fan speed is too fast on Auto. The setting labelled Fast/Soft changes the fan speed when Auto is used. I checked my settings and found that I also had the fan speed set to soft. I tried changing it to fast but it didn't make a lot of difference when I tried it, probably because the car was already warm and the system didn't need to use the fastest speed.

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27 minutes ago, Thackeray said:

air intake set to outside rather than recirculated air.

Doesn't your car automatically switch from recirc to outside?

On mine I have everything st to auto and the system invariably starts off on recirc until the desired temp is met, be that heating or, in summer, cooling.

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As long as the system is set to AUTO then it's simple physics.

When set to AUTO there will probably be a blast of cold air from the face-level vents as this is where the airflow would probably be when you last parked the car. Once the system realises that it's cold it will switch airflow to the feet area because hot air rises and the quickest way to get the whole cabin warm is to pump it out at the bottom and let it rise.

First starting the car on a warm summer day will result in the reverse operation - cold air from face (and maybe screen) vents so that it can fall and cool the whole cabin as it does so.

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56 minutes ago, NemesisUK said:

Doesn't your car automatically switch from recirc to outside?

I'm glad you asked that! I've been wondering about this very question myself recently. I'm sure I've seen it switch on occasions and the manual says it may switch in some circumstances. But recently I've been trying, without much success, to pin down when it does switch. Recently I've seen it switch to outside air when I pressed the demist button and it went back to recirculate when I turned off the demist.

But I feel it would make sense for it to switch more often than I've seen recently.  

For example, I've read elsewhere that it may switch from outside air to recirculate when in slow traffic; presumably this is to avoid taking in exhaust fumes from the car in front. I've even read that it might switch to recirculate when in a tunnel; but how it would know it's in a tunnel I don't know! Maybe a sudden switch to darkness instead of a gradual onset of night; but that would require a fairly sophisticated measurement of darkness against time.

It might make sense for it to stay on recirculate when the gear selection is ECO as this would mean there was less heating or cooling required. But in normal Drive or Sport when would you expect it to switch? What's your experience?

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