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Should recirculate be renamed to range boost mode? (Winter Tip)

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For all pre heat pumpers out there coming into winter time. Press the recirculate (range boost) button for a % range boost on longer trips!

I am not sure it gets simpler than that but it seemed to work looking at winter travel figures on SR+.

Do Tesla’s dehumidify on recirc? Growing up in Canada recirc just fogged the windows up during winter.
 
Here is my take fwiw.

Having a/c on should condense humidity out of the air, hence the drain and condensate tending to form puddles under the car. Having recirc on keeps dehumidifying and recirculating as long as the a/c is actually cooling. However when the temp setting shuts off cooling, remaining humidity sitting in the a/c gets pumped out the air vents and in the winter when the glass is likely cold, the humid air just condenses on the inside of the windows.

Having recirc off at least has fresh air coming into the cabin and makes fogging less of an issue - possibly because the a/c stays in cooling mode for longer.

I have seen other EV's tending to fog up on the inside more than ICE cars. My theory on that is that to help heating work, EV's have lower levels of cabin airflow.

In cold weather I try and avoid running a/c and keep recirc off. If the car fogs up then running a/c dehimidifies but it takes some time to get remaining humidity out of the a/c system.
 
Interesting. I've always run recirc with AC, to dehumidify faster. And, yes, it consumes less energy because you're not heating/cooling as much fresh air. Even on recirc, shouldn't about 15% of the air be fresh, or is that my imagination?
 
shouldn't about 15% of the air be fresh

I'm sure there will be a fresh air bleed, but also expect that it is less than in an ICE vehicle where energy is at less of a premium.

There are probably multiple factors making humidity build up faster and humidity reduction slower in EV's and once you get water inside (wet clothing, umbrellas, pets, footwear etc) it hangs around longer for sure.

I tend to crack diagonally opposed windows in dry weather which seems to help - particularly with condensation in the b-pillar cameras.
 
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Here is my take fwiw.

Having a/c on should condense humidity out of the air, hence the drain and condensate tending to form puddles under the car. Having recirc on keeps dehumidifying and recirculating as long as the a/c is actually cooling. However when the temp setting shuts off cooling, remaining humidity sitting in the a/c gets pumped out the air vents and in the winter when the glass is likely cold, the humid air just condenses on the inside of the windows.

Having recirc off at least has fresh air coming into the cabin and makes fogging less of an issue - possibly because the a/c stays in cooling mode for longer.

I have seen other EV's tending to fog up on the inside more than ICE cars. My theory on that is that to help heating work, EV's have lower levels of cabin airflow.

In cold weather I try and avoid running a/c and keep recirc off. If the car fogs up then running a/c dehimidifies but it takes some time to get remaining humidity out of the a/c system.
ice cars run the AC even when the heat is on to keep the windows clear..
 
Doesn’t it turn off the AC when using recirc? If so it is a perfect way to risk fogging up windows on the car, especially when theres snow being dragged in which melts and makes the air inside more humid.

it doesnt, and the AC/HVAC automatically switches recirc on when its gets too hot or too cold outside but will momentarily switch it off every once in a while to recirculate fresh o2.
 
I always have recirc thurned off. I like fresh, dry air.

Unless its 0% humidity outside recirc will give you drier air than pulling it from outside. If you live in the tropics or in naturally humid cold weather (i.e. middle europe) you turn recirc on for non fresh dry air. non recirc can do the same but it then has to run the AC to cool/dehumidify the air and then heat it up so recirc is preferable and the car will automatically switch to that if in automatic mode.
 
it doesnt, and the AC/HVAC automatically switches recirc on when its gets too hot or too cold outside but will momentarily switch it off every once in a while to recirculate fresh o2.

Yeah in the wintertime Auto doesn’t really work as it isn’t running the AC to dehumidify enough. Always had to use manual during winter in my S to avoid fogged windows. They might have changed this lately but it really does need to run all the time in the winter to avoid building up humid air inside.
 
it really does need to run all the time in the winter to avoid building up humid air inside.

Once you start running ac, I agree that it is hard or impossible to kick the habit. However I found that trying very hard to NEVER use recirculation and only ac as a last resort works ok. Imagine having a car from the 60's where all you could do was turn on the (pathetic) heater and keep the windows open to get the hot (tepid) humid air out of the car.

Not ideal, and imo not helped at all with heat pumps. The heat pump either heats or cools, and as it switches between those two modes you can get some extreme humidity events!
 
Yeah in the wintertime Auto doesn’t really work as it isn’t running the AC to dehumidify enough. Always had to use manual during winter in my S to avoid fogged windows. They might have changed this lately but it really does need to run all the time in the winter to avoid building up humid air inside.

put on cold window defogger or enable the top vents (if its otherwise comfortable in the cabin)
 
Can confirm that recirculation is a terrible idea (at least in the UK) for visibility.

Even in completely dry clothes, 30miles into a journey, and even in relatively dry outside weather, putting recirc on for any length of time will lead to dense fogging.

put it on recirc and press the window defog button. its designed for humid cold weather i.e. uk.
Humid warm weather like here in the tropics AC on its own dehumidifes the air enough so that it wont be an issue.