Member Since: 01 Jan 2014
Location: hampshire
Posts: 340
Mine never fogged up but I had little idea how the heater worked I am better with a big dial and single speed toggle switch. I only had auto climate if it was hot. Otherwise the air con was off otherwise it will eat fuel for no reason. You don't need the air con on if it's 8 degreesD4
5th Jan 2015 11:30 pm
Kimi
Member Since: 26 Mar 2013
Location: Home
Posts: 62
JonM wrote:
Mine mists up occasionally on auto.
The car sometimes decides to maintain a nice comfortable cabin temperature by only using the lower vents, it doesn't blow any air through the demister vents, so the windscreen and side windows get a bit of mist.
Using the buttons to redirect the airflow solves it.
It doesn't do it very often - most of the time it works perfectly on auto. It must just be a particular set of conditions that cause it to not demist.
Here in Finland now that we have freezing temperatures, this happens quite often. So I need to switch from auto to manual control regularly to avoid misting. I'm not sure what's the logic to blow to feet only when it's cold and windows may potentially freeze or mist.
5th Jan 2015 11:38 pm
promitheus
Member Since: 04 Jul 2009
Location: Afidnes, Greece
Posts: 572
After using, measuring and trying to fix my CC recirculation flap issue since I bought my new D4 MY14 back in Dec 2013, I have reached a point where I may say that I know exactly how the D4 CC works under different circumstances (especially for MY14 vehicles, since these include a temperature/humidity sensor located on the windscreen which makes things even more complicated). With the help of my IID Tool (many many thanks to the GAP team ) I have collected many live value graphs regarding how these magical but complicated devices work. I'm currently preparing a short HVAC manual with all the details and will publish it for all fellow members, as soon as I get some reference values from Wiggs for comparison sake and in order to come to some safe conclusions.
From my measurements till now I can say that if outside temperature is under 4 deg C, then it is very possible that you'll get some moisture especially on the side windows. When car is parked in such cold conditions relative humidity on the windscreen is around 55% and can climb up to 60-65%. The CC tries its best to bring this down to a comfortable level of around 40%, which is quite difficult if the ambient atmosphere is very humid and cold. Please also note that when outside temp is say 2 deg and you set the CC to 21 for example the air condition pressure goes as low as ~200kPa to allow the temp to quickly rise, so the evaporator effectiveness is limited.
Important note: for my14+ vehicles the recirculation flap is not allowed to completely close under the above circumstances. On my13 and before vehicles pressing the recirc flap will close the flap completely. Doing so makes dehumidifying the cab air even more difficult, so you should not do that in very cold weather. My advice is to let the cc work in Auto for as long as necessary and use the windscreen heating function and MAX defrost function to help it out.
Regarding the recalibration function, this does not work on D4, only on D3's. In order to recalibrate or initialise the HVAC, you'd need an IID Tool which can greatly help you diagnose all HVAC issues (and more ).
Hope that helped, will be back with my complete more scientific story soon...
6th Jan 2015 12:02 am
promitheus
Member Since: 04 Jul 2009
Location: Afidnes, Greece
Posts: 572
Kimi wrote:
...I'm not sure what's the logic to blow to feet only when it's cold and windows may potentially freeze or mist.
Just saw your post Kimi...
The inclusion of the temp/humidity sensor on MY14+ D4's serves exactly that purpose. When temps are close to freezing, the HVAC will automatically turn the windscreen heating on to avoid that. The HVAC reads the windscreen surface temp and windscreen air temp and if they are too low will activate the windscreen and rear window heating elements.
I do realise what you are saying about the MAX defrost function helping in such conditions, but I guess that blowing warm air to the lower part makes the cabin reach a comfortable temperature sooner, as warm air moves immediately up.
6th Jan 2015 12:14 am
Kimi
Member Since: 26 Mar 2013
Location: Home
Posts: 62
I think there are problems also in MY14+ solution:
1) It only targets the windscreen (and only partially that, leaving 1-2 inches on the sides still misted)
2) Side windows are still misted.
I realize cabin is more evenly heated when most of the air is directed down, but LR's decision to direct ALL air down is just wrong. This hasn't been an issue with my previous cars, since auto mode still directed some air to windows even when major portion was sent down. With D4 the auto mode is more or less useless so you end up doing all manually (effectively you have a manual A/C during winter time).
Another issue is with MAX mode. When pressed, it uses max fan speed (directed probably mostly to windows) and turns windscreen and rear heaters on. All good so far. But when you press it again to turn it off you would expect all settings to return to previous values. But my D4 still leaves windscreen and rear heaters active, so I always have to manually turn them off. Well, this happens also every time I start the car in cold temperatures, but that's another topic.
I think this system hasn't been tested enough in real winter. I was able to spot many of these problems quite early in my D4 (MY10 that is) ownership.
7th Jan 2015 3:11 pm
Hedgehog
Member Since: 27 Mar 2010
Location: Frankonia
Posts: 100
I totally agree with Kimi.
There must be another solution than switching an automatic system to manual. Also on mine (without heated windscreen) in auto mod with ambient temps between -2 to +4° C in good old Germany you you will get at least one foot roasted by the heater but always keep a cool head and arm and shoulder (from the side window) what is very uncomfortable . Also the side and parts of the front window start to fog up regulary. And this also occures during long distance driving with cleaned windows without using recirculating and not only when you are entering the vehicle with damp clothes or shoes.
Since I have heard the dealers are able to change the settings there should be a possibilty with the MSV-2, isn´t it
What I have seen the annoying auto-on for the front- and rear window heating is changeable with the Faultmate.
Cheers
HedgehogHedgehog
Defender 110 HSE 3.0 i-6 Diesel MHEV - Fuji white / acorn coming soon (hopefully)
Jeep Wrangler JKU Sahara Indian Summer gone
Disco 5 Luxury Aruba / Light Oyster gone
Discovery 4 - gone but not forgotten -
Discovery 3 with some add ons - gone
7th Jan 2015 4:18 pm
FenRob
Member Since: 24 Mar 2014
Location: Fenland, Cambs
Posts: 130
I have exactly the same issue on MY14 (and noticed the same on my neighbour's MY 13.5 RRS which is basically the same) .... front side windows misting up heavily and light mist on windscreen when climate is on auto and it's cold and damp.
A quick burst of "max windscreen" clears it within a few seconds, then back to auto. But that does rather defeat the idea of having auto.
7th Jan 2015 5:14 pm
Iguana
Member Since: 14 Oct 2013
Location: 'Sunny' Zomerset
Posts: 9421
Drove about 1hr in the rain last week and whatever I did, the whole screen and side windows was Mister up, had to have front and rear heater on nearly all the time.....car was full of walking kit, one dog and three blokes, so put it down to something damp inside the car.
Next day, exactly the same thing, as we drove early for a Brecon walking session, 30 mins into the drive I noticed that the re-circulation button was on
5 mins after switching this off, everything was clear........so it could be something simple like that Iggy/Ieuan
Current LR =
2015 RR Sport Autobiography
&
1992 Land Rover Defender Camper
- Gone but not forgotten:
MY10 D4 GS
MY05 Disco 3 'S'
MY14 FL2 HSE manual in Blue
MY15 Disco 4 HSE Lux in Santorini Black
MY08 Disco 3 SE manual in Buck Blue
1960 Series 2 88" (No idea why I sold it!)
7th Jan 2015 5:23 pm
motolite
Member Since: 18 Mar 2013
Location: Sydney
Posts: 931
I thought this was a post about getting misty eyed when SWMBO takes the D4 keys
sorry, too many coffees, I'll leave now.
8th Jan 2015 12:14 am
stenh02
Member Since: 01 Jul 2009
Location: Up North
Posts: 270
So, are we saying that this misting up in outside temps below, say, 5 degree Celsius is another LR special effect for the D4? Our D4 is 2 weeks old and misting up side rear windows is very noticeable on Auto setting.
11th Jan 2015 6:06 pm
Robbie
Member Since: 05 Feb 2006
Location: ¯\_(ツ)_/¯
Posts: 17932
I'd get it checked. If the actuators on the recirc door are out of calibration you will be forever fighting with it. Misting with AC on auto is not acceptable. Once cleared of mist using the demist buttons it should stay clear (well ignoring a stupidly wet interior / people / dogs, but you get the idea).
Land Rover - Turning Drivers into Mechanics Since 1948
Member Since: 01 Jul 2009
Location: Up North
Posts: 270
Cheers Robbie.
Will give the dealer a bell and get it looked at.
11th Jan 2015 8:12 pm
promitheus
Member Since: 04 Jul 2009
Location: Afidnes, Greece
Posts: 572
It could be a recalibration issue, but I'd say it's normal when outside temp is near 0. You have to use MAX to cure this.
Regarding MY14+:
...however, I have run tens of tests with the HVAC and I can assure you people that no matter how hard the a/c tries, if outside temp is near 0, the cabin windscreen relative humidity just does not drop below 42%. At this level of humidity and with outside temps approaching zero (and below), it's not easy to keep moist on windows away. This is without any sunshine, especially at night. Sun can greatly affect the cabin conditions. Using the MAX button will demist your windscreen and front side windows. If A/C set to AUTO, you may get mist if temps approach zero. I would consider that to be normal, especially when you first start the car - humidity may reach 75% easily then.
The main difference with MY13- models is that the ATC does not have a specific windscreen humidity and temps reading/sensor to take into account, so the dehumidify function is automatically controlled just be the evaporator control valve.
BTW, if anyone has a MY14+ and an IIDTool, I would be very much interested if you could run some tests, so that we may reach some more robust conclusions, which I will soon publish for everyone to have. Please PM me, so that I can give you the log values and test conditions.
11th Jan 2015 10:41 pm
Robbie
Member Since: 05 Feb 2006
Location: ¯\_(ツ)_/¯
Posts: 17932
That would be interesting if the recent enhancements have made things worse.
Still, complaining to the dealer is the first start to getting a change.Land Rover - Turning Drivers into Mechanics Since 1948
Member Since: 01 Jul 2009
Location: Up North
Posts: 270
It does seem naff that the AC can't stop misting when all other LR products (well maybe not the 90) I've owned cope well no matter what temp, day or night.
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
) I have collected many live value graphs regarding how these magical but complicated devices work. I'm currently preparing a short HVAC manual with all the details and will publish it for all fellow members, as soon as I get some reference values from Wiggs for comparison sake and in order to come to some safe conclusions.
).
At this level of humidity and with outside temps approaching zero (and below), it's not easy to keep moist on windows away. This is without any sunshine, especially at night. Sun can greatly affect the cabin conditions. Using the MAX button will demist your windscreen and front side windows. If A/C set to AUTO, you may get mist if temps approach zero. I would consider that to be normal, especially when you first start the car - humidity may reach 75% easily then.
