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Ice on the inside of the windows

1669 Views 20 Replies 13 Participants Last post by  CosmoK
I'm so done with the window issues! It's bad enough my driver side window won't close when it's wet out and the windows always being foggy, now I have to scrape the inside of my windows. Living in Midwest, we get cold. This morning -11. I have an hour commute to work. I had the defroster on high for the whole hour. The sides of the windshield, and all side windows were frosted! This is my first Subaru. It will be last. Does anyone have the same issue? and maybe a fix for this?
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I have terrible fogging issues with the windows. Have had this problem since it was new. I run defroster but it immediately dogs off defroster is turned off.
I have terrible fogging issues with the windows. Have had this problem since it was new. I run defroster but it immediately dogs off defroster is turned off.
My foggy issue also has been since beginning.
ice on the inside sounds very wrong to me. have you brought it into the dealer? sounds like a bad seal somewhere?
I'm so done with the window issues! It's bad enough my driver side window won't close when it's wet out and the windows always being foggy, now I have to scrape the inside of my windows. Living in Midwest, we get cold. This morning -11. I have an hour commute to work. I had the defroster on high for the whole hour. The sides of the windshield, and all side windows were frosted! This is my first Subaru. It will be last. Does anyone have the same issue? and maybe a fix for this?
It's not a Subaru-specific thing, and this does not mean that there's anything wrong with the vehicle itself. Virtually all vehicles can experience this kind of an issue, under the right conditions. A quick Google search will show that this is a problem that's reported throughout car-dom, and that even luxury vehicles with double-pane windows can experience "inside frosting/icing."

Frost on the inside of the vehicles' glasshouse is typically due to freezing of the moisture that's left in the vehicle after you've exited.

Being sure to run the vehicle's HVAC system with the "A/C" turned "ON" and the recirculation function turned "OFF" can help mitigate this issue to some degree as you're dehumidifying (i.e. defogging) during the time you -the item that likely is producing the most moisture- are in the vehicle. Allowing the moist air inside to escape by leaving one or more windows partially open (and yes, being a snow-belt resident, I do understand that this may not always be possible 😅 if you park that vehicle outside) if you garage the vehicle, can also be a viable solution (ironically, driving with the window cracked open in order to get rid of fogging during one's drive can lead to fogging/frosting after the vehicle is parked, as the outside air coming in the window is not dehumidified by the vehicles A/C system). Additionally, insuring that your windows' interior surfaces are clean and free of dust (which allows the moisture something to "grab on to") will also help mitigate, as well as trying to insure that the interior of your vehicle -including the carpet/mats, but also things like snow-brushes, gloves, coats, hats -anything that may be left in the vehicle- are as free of moisture and wetness as possible.

So far this winter, my daughter's car ('19 Legacy) has only experienced interior frosting on one occasion. As-expected, it wasn't on the coldest day - but rather on a day where there was just more wetness: there was a lot of snowfall, and so when she cleared the snow from the vehicle for the drive home from school or rowing, that wetness was tracked inside the car.

One thing to be cognizant of in terms of interior fogging (and later frosting) is also the number of passengers you are carrying. For single commuters on shorter rides, the car's interior may never fog, even if the HVAC is not set optimally for defogging - now, add another passenger or two...it becomes fog-city. Who that passenger is can also affect fogging and subsequent fogging. This winter, my mother-in-law was surprised that her windows had started fogging so quickly when the two of us set out on a route-finding trip together, mentioning that when she's alone in her '21 Forester for her typically short shopping jaunts or visiting friends, she usually doesn't have an issue. She then proceeded to tell me that the windows do fog up as her drive-time increased. I convinced her to allow me to help her adjust her HVAC settings, and she's confessed that she hasn't seen an issue, since. Similarly, the "type" of passenger(s) matters, too. When my daughter and I are in a vehicle together -since we both "run hot"- fogging comes on much, much quicker. Put that 100-lb. German Shepherd in the back? see how fast he fogs the entire cabin. 😜

How you use the vehicle can also affect outcome: if the last use of your vehicle (before it's parked for the night, outside on a sub-freezing night) is a 5-minute zip home after you've just worked out at the gym or come out of a post-shift shower, that's also more likely to cause issues.

One thing that I've seen mentioned online that I personally have never tried is to use some form of desiccant inside the vehicle.
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Turn your Re-Circ off.
I'll try that! i run the Re-Circ because when it's off, it smells like gas inside. (only in the cold) this problem is in other threads.
It's not a Subaru-specific thing, and this does not mean that there's anything wrong with the vehicle itself. Virtually all vehicles can experience this kind of an issue, under the right conditions. A quick Google search will show that this is a problem that's reported throughout car-dom, and that even luxury vehicles with double-pane windows can experience "inside frosting/icing."

Frost on the inside of the vehicles' glasshouse is typically due to freezing of the moisture that's left in the vehicle after you've exited.

Being sure to run the vehicle's HVAC system with the "A/C" turned "ON" and the recirculation function turned "OFF" can help mitigate this issue to some degree as you're dehumidifying (i.e. defogging) during the time you -the item that likely is producing the most moisture- are in the vehicle. Allowing the moist air inside to escape by leaving one or more windows partially open (and yes, being a snow-belt resident, I do understand that this may not always be possible 😅 if you park that vehicle outside) if you garage the vehicle, can also be a viable solution (ironically, driving with the window cracked open in order to get rid of fogging during one's drive can lead to fogging/frosting after the vehicle is parked, as the outside air coming in the window is not dehumidified by the vehicles A/C system). Additionally, insuring that your windows' interior surfaces are clean and free of dust (which allows the moisture something to "grab on to") will also help mitigate, as well as trying to insure that the interior of your vehicle -including the carpet/mats, but also things like snow-brushes, gloves, coats, hats -anything that may be left in the vehicle- are as free of moisture and wetness as possible.

So far this winter, my daughter's car ('19 Legacy) has only experienced interior frosting on one occasion. As-expected, it wasn't on the coldest day - but rather on a day where there was just more wetness: there was a lot of snowfall, and so when she cleared the snow from the vehicle for the drive home from school or rowing, that wetness was tracked inside the car.

One thing to be cognizant of in terms of interior fogging (and later frosting) is also the number of passengers you are carrying. For single commuters on shorter rides, the car's interior may never fog, even if the HVAC is not set optimally for defogging - now, add another passenger or two...it becomes fog-city. Who that passenger is can also affect fogging and subsequent fogging. This winter, my mother-in-law was surprised that her windows had started fogging so quickly when the two of us set out on a route-finding trip together, mentioning that when she's alone in her '21 Forester for her typically short shopping jaunts or visiting friends, she usually doesn't have an issue. She then proceeded to tell me that the windows do fog up as her drive-time increased. I convinced her to allow me to help her adjust her HVAC settings, and she's confessed that she hasn't seen an issue, since. Similarly, the "type" of passenger(s) matters, too. When my daughter and I are in a vehicle together -since we both "run hot"- fogging comes on much, much quicker. Put that 100-lb. German Shepherd in the back? see how fast he fogs the entire cabin. 😜

How you use the vehicle can also affect outcome: if the last use of your vehicle (before it's parked for the night, outside on a sub-freezing night) is a 5-minute zip home after you've just worked out at the gym or come out of a post-shift shower, that's also more likely to cause issues.

One thing that I've seen mentioned online that I personally have never tried is to use some form of desiccant inside the vehicle.
Thanks for all that info! I had my kids in the car w/me before my drive to work...so definitely more bodies in there.
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Yes, thank you for the write up. Very informative and helpful. I did not know this was a thing that could happen.
yes, it is in other threads, and it is always because the re-circ damper is broken/stuck, or driver has pushed the re-circ button.
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I'll try that! i run the Re-Circ because when it's off, it smells like gas inside. (only in the cold) this problem is in other threads.
Recirc is never to be used with the heat, only AC. I don't recall, but I'll bet the owners manual notes this.
I'll try that! i run the Re-Circ because when it's off, it smells like gas inside. (only in the cold) this problem is in other threads.
When cold out and need to warm car for 10 +min, I turn the Re Circ on while the car is warming, this stops the gas smell from happening. After I turn around and heading down the road I turn it off, and put the defrost on. When there is almost a full load of ice in my Husky floor mats, I pull them out while still frozen and kick the back side to clean. Two big labs panting can change that a little, lol
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I'll try that! i run the Re-Circ because when it's off, it smells like gas inside. (only in the cold) this problem is in other threads.
Recirculating air results in inside window fogging. Turn off recirculate and your problem will go away.
Additionally, insuring that your windows' interior surfaces are clean and free of dust (which allows the moisture something to "grab on to") will also help mitigate, as well as trying to insure that the interior of your vehicle -including the carpet/mats, but also things like snow-brushes, gloves, coats, hats -anything that may be left in the vehicle- are as free of moisture and wetness as possible.
On the money with cleaning the windows. When I lived on damp, cold Long Island, I had a Celica with terrible outgassing that created a film that attracted more fog. I had to clean the windows weekly.
German Shepherd in the back? see how fast he fogs the entire cabin. 😜
My two pant directly onto the windows. Rear windows fog all the time. Plus they're coated with an impenetrable layer of spit that's really hard to clean after the sun hits it.
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My two pant directly onto the windows. Rear windows fog all the time. Plus they're coated with an impenetrable layer of spit that's really hard to clean after the sun hits it.
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Recirculating air results in inside window fogging. Turn off recirculate and your problem will go away.
Not if there's no source of moisture in the vehicle, ie people breathing.
Recirc is great if you're warming the car up before getting in. With the AC compressor on it'll actually make the air inside dryer than if it were bringing in outside air. Once the doors are opened and people get in its a complete different story.
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Tell me that is true of sub-zero temps F. AC compressor does not run, and as car warms up and melts ice on floor mats turns to vapor and collects on windows as frost.
Above 30F, your scenario is accurate.
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Sure. It’s dependent on the relative humidity outside. If the outside air is dryer, which is likely is when it’s that cold outside, don’t recirc.
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I'm so done with the window issues! It's bad enough my driver side window won't close when it's wet out and the windows always being foggy, now I have to scrape the inside of my windows. Living in Midwest, we get cold. This morning -11. I have an hour commute to work. I had the defroster on high for the whole hour. The sides of the windshield, and all side windows were frosted! This is my first Subaru. It will be last. Does anyone have the same issue? and maybe a fix for this?
yup - same thing here. First car I have ever had do that… and i have had several old and new. I’m wondering if water is sneaking in somewhere and into the carpet. One day i pulled out my driver side rubber floor mat and saw ice on the bottom of it. Check yours sometime
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I'm so done with the window issues! It's bad enough my driver side window won't close when it's wet out and the windows always being foggy, now I have to scrape the inside of my windows. Living in Midwest, we get cold. This morning -11. I have an hour commute to work. I had the defroster on high for the whole hour. The sides of the windshield, and all side windows were frosted! This is my first Subaru. It will be last. Does anyone have the same issue? and maybe a fix for this?
Check the floor mats to see if they are wet, could be a leak,
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