Condensation on windshield on the inside

[dark cloud]

This problem comes with the V9 software version. It handles the climate control settings differently rendering the auto settings pretty much useless when handling windows fogging. I've never ever had this problem prior V9.

I am not disagreeing with you, but have you investigated maybe the interior of the windows have just gotten dirty? About the same time V9 came out? Coincidence?

Dirty windows fog more easily than clean ones.

Additionally my windows fog more on mornings than any other time. Why? open coffee.

 

[David29]

I have had this problem only rarely in my Tesla, and mainly when we had a lot of snow so that moisture ends up on the floor from shoes/boots. My car is parked outside all year. In winter, once moisture is in the car, it is difficult to get it out. Same thing has happened in other cars and I have not noticed the Tesla is any worse, but the interior of the Model S (and X) is huge so that could possibly account for increased problem observed by the OP.
This winter we have (remarkably) had no measurable snow, so no inside icing or fogging yet. So, i cannot say whether or not version 9 has made a difference. But this does add to my concern about the difficulty of operating the HVAC controls manually with version 9 -- that is a maddening restriction!

 

[Saimaannorppa]

Well here is what BMW says:

BMW Air Conditioning Recharge.
If you find that you are unable to achieve a comfortable temperature or de-fog your windscreen on a cold morning, your car may need an air conditioning recharge...

This is a different service than desiccant replacement. All air conditioning systems need recharge of fluids at times, depending on how well sealed they are. Btw. this can be done anywhere, don’t need to go to SC or a stealer.

I am not disagreeing with you, but have you investigated maybe the interior of the windows have just gotten dirty? About the same time V9 came out? Coincidence?

Dirty windows fog more easily than clean ones.

Additionally my windows fog more on mornings than any other time. Why? open coffee.

My observation is that v9 indeed changes the A/C auto mode logic, and auto mode tries to deactivate A/C and use recirculation even when this is not optimal.

 

[aesculus]

Wonder if the more recent SW versions force the car back to recirc whereas perhaps previous versions remembered the previous setting?

For my recent tests it seems to be temperature dependant on when it does this. I thought in the past (pre V9) it ALWAYS used outside air unless you forced it to recirculate but I did not do extensive tests of this.

 

[aesculus]

I am not disagreeing with you, but have you investigated maybe the interior of the windows have just gotten dirty? About the same time V9 came out? Coincidence?

I can get in the car dry and move to a colder/moister area and it fogs up. I can also tell you my interior windows are spotless.

V9 has changed the way the system operates dramatically, perhaps the biggest impact is turning on recirculate and turning off A/C when outside temps are below 40F and on Auto. This IMHO is probably the biggest impact that is causing my fogging.

I will report this to Tesla via customer service feedback.

 

[TSLA Pilot]

For people in colder climates using manual settings who turn off the A/C, a reminder to ensure you engage it regularly to extend life of the system. I am not sure if Tesla has programmed the computer to make sure it cycles regularly or not, but not using the A/C system is what kills it.

That was, IIRC, only because the clutch seal would dry out if not used.

In the case of Tesla's HVAC, the entire system is sealed and there is no external clutch seal that would require lubrication.

 

[dark cloud]

That was, IIRC, only because the clutch seal would dry out if not used.

In the case of Tesla's HVAC, the entire system is sealed and there is no external clutch seal that would require lubrication.

I was thinking more in terms of the seals drying out from lack of periodic lubrication.

This is a different service than desiccant replacement. All air conditioning systems need recharge of fluids at times, depending on how well sealed they are. Btw. this can be done anywhere, don’t need to go to SC or a stealer.

As @TSLA Pilot was pointing out, I don't know of any other manufacturer that specifies changing the desiccant bag, but doing so means the A/C system is opened and therefore doing this procedure ensures a recharge and re-lubricating of the system, which of course is good for longevity, but my point was if the system were only operating at 50% efficiency due to the fact that some A/C systems using R134 can loose a reported 10-15% of their gas per year, this may make some cars work a lot harder and take a lot longer to remove the cars moisture, as the BMW ad pointed to.

My observation is that v9 indeed changes the A/C auto mode logic, and auto mode tries to deactivate A/C and use recirculation even when this is not optimal.

V9 has changed the way the system operates dramatically, perhaps the biggest impact is turning on recirculate and turning off A/C when outside temps are below 40F and on Auto. This IMHO is probably the biggest impact that is causing my fogging.

I will report this to Tesla via customer service feedback.

Tesla seriously turns off the A/C on ultra-cold days? I hadn't noticed. Recirculating moist air is not what should be done! I have had to turn on the defrost button, and that seems to work to defog the windows, so it must turn on A/C methinks, but I am going to pay more attention next time and see what is going on.

 

[David29]

...

Tesla seriously turns off the A/C on ultra-cold days? I hadn't noticed. Recirculating moist air is not what should be done! I have had to turn on the defrost button, and that seems to work to defog the windows, so it must turn on A/C methinks, but I am going to pay more attention next time and see what is going on.

Every other car I have owned in the past automatically shut off the A/C compressor when the outside air temp is below freezing. I thought the purpose was to prevent freeze-up of the condenser coils. Is there some reason Tesla's system would be different?