Do you use A/C during winter driving?

[davidand]

I'd be interested to share my experiences with winter driving of my Model 3 in terms of using / not using A/C.

My thoughts are:
- Whenever climate is set to Auto, the Model 3 (almost) always turns on A/C. It's not just the blue button, it's the smell of the A/C-treated air, it's surely running.
- Using ScanMyTesla (on iPhone) I measured that it takes roughly 1 kW of energy to keep the A/C running - which is significant.
- I don't see any advantage of the A/C being on except for very heavy rain in connection with air re-circulation active.
- Because of the above, I keep climate on Manual all the time which is not super-convenient. Also in dog mode / camp mode / climate on mode (when leaving the car) A/C just turns on.

I'd be interested in your experiences:
- Any thoughts on A/C getting smelly over time? Is it better to run it all-year-long? I my Toyota I had clear benefits of not running the A/C in winter as the car didn't get smelly after engine (and A/C) start.
- Anyone also concerned about power consumption (A/C takes as much power as heating, therefore A/C + heating doubles the HVAC consumption in winter). Do you turn it off or you just don't worry about this?
- Does anyone religiously turn off A/C when not needed (just like me)?

 

[Braumin]

Most cars run the AC in the winter because it will remove moisture from the air which prevents the windows fogging up.

If your car has a heat pump (you didn't say what year yours was) then the compressor is going to be running anyway. The heat pump can also use the compressor to generate heat.

 

[scrapps]

Just wanted to add that in the 3 years of owning my 2018 I've had to have the AC system cleaned and a filter replacement, because of the bad smell, at about $122 each time. Not sure if it's normal to have to clean out the AC system regularly on cars? Seems like a design issue.

 

[Braumin]

I think it is a design issue on the smell. My 2021 hasn't had the problem (at least so far) so maybe they have it fixed now with the heat pump system.

 

[jjrandorin]

To answer the question posed in the thread title, yes, I have the climate control system on at all times when driving the vehicle, no matter what season it is.

I have it set to 70 degrees and Auto from April to October, and at 72 degrees and Auto from October to March. Whether it runs A/C or Heat etc I dont really pay attention to because I dont think of the climate control system in a car as "heating OR cooling", for me its "I want the car at or around this temperature, do what you need to do that" (thus I am calling it climate control and not "A/C").

When the car is below the set temp, the heat runs, when its above it, the AC will run. I also am a person who drives with all windows UP at all times, though, with recirc off to get in fresh air, vs rolling down windows. I realize those are personal choices everyone makes.

 

[Amped412]

Yea the cars have a relative humidity sensor. If it senses high enough humidity it’ll turn on AC to dehumidify the cabin.

 

[Rocky_H]

Does anyone religiously turn off A/C when not needed (just like me)?

Hallelujah! You read my mind, and I agree with every bit of your comment! I am probably one of the few who will say this though. I have an old 2014 Model S. It has always bugged the hell out of me how the car tries to run the air conditioning in the Winter. It's F&^#$ing stupid! It's Winter. The outside air is dry. Just keep outside air coming in, and it will keep the windows not fogged up. It's the damn recirculate that is trapping the moisture inside and CAUSING the windows to fog, which is then why the car tries to run the A/C to undo its own bad decision. *grumble*

So yes, I keep it on manual all the time, and I specifically turn the A/C off and outside air coming in. I don't have the heat pump, so it's not running the compressor all the time, and I just don't want it wearing that out by running it year round.

 

[Ther0ck]

Just wanted to add that in the 3 years of owning my 2018 I've had to have the AC system cleaned and a filter replacement, because of the bad smell, at about $122 each time. Not sure if it's normal to have to clean out the AC system regularly on cars? Seems like a design issue.

Doesn't it say in the manual to change the filters every 2 years ? I saw a lot that change them after 1 since they do a lot of kms.

Edit. Some are adding a screen where the air comes in to avoid debris to come in and help the smell and avoid unnecessary cleaning.

 

[DonF]

I'd be interested to share my experiences with winter driving of my Model 3 in terms of using / not using A/C.

My thoughts are:
- Whenever climate is set to Auto, the Model 3 (almost) always turns on A/C. It's not just the blue button, it's the smell of the A/C-treated air, it's surely running.
- Using ScanMyTesla (on iPhone) I measured that it takes roughly 1 kW of energy to keep the A/C running - which is significant.
- I don't see any advantage of the A/C being on except for very heavy rain in connection with air re-circulation active.
- Because of the above, I keep climate on Manual all the time which is not super-convenient. Also in dog mode / camp mode / climate on mode (when leaving the car) A/C just turns on.

I'd be interested in your experiences:
- Any thoughts on A/C getting smelly over time? Is it better to run it all-year-long? I my Toyota I had clear benefits of not running the A/C in winter as the car didn't get smelly after engine (and A/C) start.
- Anyone also concerned about power consumption (A/C takes as much power as heating, therefore A/C + heating doubles the HVAC consumption in winter). Do you turn it off or you just don't worry about this?
- Does anyone religiously turn off A/C when not needed (just like me)?

Yes, I keep mine on manual all the time. Now with v11.0, I can't heat my seats without going into climate which turns on the air conditioning! If I need to heat my seats, why would I want a/c? Nuts.

 

[DonF]

Just wanted to add that in the 3 years of owning my 2018 I've had to have the AC system cleaned and a filter replacement, because of the bad smell, at about $122 each time. Not sure if it's normal to have to clean out the AC system regularly on cars? Seems like a design issue.

Get used to the smell. The Model 3 has a design flaw. A service manager that actually talked to me after I complained to corporate Tesla all but admitted it. He cleaned my system for free.

 

[Gasaraki]

Yes. The A/C runs because you are breathing. When you have people in an enclosed space all breathing, moisture gets exhaled. Moisture hitting a cold glass causes fogging. Putting warm dry air in to the cabin lets the air hold more moisture, therefore less condensation.

 

[ATPMSD]

If your car has a heat pump

This is an interesting question. In the winter the only time we actually need to run the AC is when the air is being recirculated. But how can we get both AC and Heat out of a heat pump? Do cars with a heat pump allow you to recirculate the air?

 

[Gasaraki]

A/C does not = cold air
Heat does not = A/C off

A/C is air conditioner. Air conditioners condition the air, NOT JUST COOL IT. You can have the AC running while the temperature is set high. All cars with an automatic climate control will turn on the A/C when it detects high humidity inside the car. Doesn't matter if the recirculate is on, doesn't matter if the temperate is set to 80.

My 08 Subaru Legacy will actually automatically turn on the AC when the front defrosters are turned on no matter the temperature set.

 

[Gasaraki]

This is an interesting question. In the winter the only time we actually need to run the AC is when the air is being recirculated. But how can we get both AC and Heat out of a heat pump? Do cars with a heat pump allow you to recirculate the air?

A heat pump is an AC unit. The only difference is a heat pump can reverse the flow of "coolant". (Obviously very simplified)

 

[ATPMSD]

A heat pump is an AC unit. The only difference is a heat pump can reverse the flow of "coolant". (Obviously very simplified)

Correct but that is not the question. You correctly stated how they work in that a Heat Pump has the ability to produce cold air or hot air. In an ICE car, in the winter the AC cools the air (removing humidity) then the air continues to the car’s heat system where it is heated before it enters the cabin. I do not see how a car with a heat pump can accomplish this since the heat pump provides either heated or cooled air, but not both.

Therefore, in a car with a heat pump that is set to recirculate, there does not seem to be a way to dehumidify the air before it is heated.

 

[jjrandorin]

Get used to the smell. The Model 3 has a design flaw. A service manager that actually talked to me after I complained to corporate Tesla all but admitted it. He cleaned my system for free.

I havent had to do this since they changed the algorithms in 2019, but I suspect if you are also someone who tries to turn off the AC all the time in a model 3, you will end up doing this more often (because the system attempts to run to dry out the filters).

Basically, if you leave it on Auto, set to a temperature in a model 3 (and stop trying to micromanage when the AC comes on and when it doesnt), you will likely experience the problem of "stinky AC" less or not at all.

 

[Rocky_H]

Maybe this needs more explanation.

A/C does not = cold air
Heat does not = A/C off

A/C is air conditioner. Air conditioners condition the air, NOT JUST COOL IT.

A/C does chill the air and make it colder. That is literally what it does. If you don't think it does that, I wonder what you think "conditioning" means.

Now there are different stages in the process, though. As an end result at the end of the whole thing, yes, you can have hot air. But that is after it has gone through this process of having the air chilled colder, which condenses the water out of it as a side effect, and then having to go to the heating system to spend EVEN MORE energy heating the air back up, more than the energy it would have needed if the car hadn't pre-chilled it with the A/C. In a gas car, that makes no difference, because there is so much excess heat, the heating part costs nothing. But in an electric car? That is a really irritating increase of energy consumption as the car is making extra work fighting against itself with continually chilling and heating the air at the same time. It increases the consumption pretty noticeably, and is really unnecessary.

Yes. The A/C runs because you are breathing.

More specifically, because it's on recirculate. Because it's recirculating that breath air, it's continually adding to the moisture, making the humidity % really high and therefore having the car sensors decide it needs to dry the air out. The air would stay dry if it were not recirculating.

 

[jjrandorin]

More specifically, because it's on recirculate. Because it's recirculating that breath air, it's continually adding to the moisture, making the humidity % really high and therefore having the car sensors decide it needs to dry the air out. The air would stay dry if it were not recirculating.

Maybe its different in your car, but in my model 3 on auto in the climate control, recirc. is off (which is how I want it) almost all the time. I have the system on but want recirc, and have not had to do anything specific to get that to happen.