Fan Only: Peculiarities of the Model 3

[SageBrush]

I'd like to spell out a couple different uses of fan only and implementation details. I'll need help on most of it and will try to update this OP with a moderator's help when it is well flushed out.

1. The easy one is fan only while driving. This just requires that Auto and AC be greyed out in the climate screen. The fan speed is the only control active.

2. Cabin overheat protection:

3. Car pre-conditioning using the mobile App:

 

[ewoodrick]

Are you asking a question? Stating a fact? I'm not really sure what you are trying to say.

 

[SageBrush]

For (2) and (3) I would like to know how to use the fan only.

 

[SDKoala]

Fan only is an option for cabin overheat protection that can be set. There's no option to turn on the fan only through the app; temp is the only thing you can set.

 

[jsmay311]

1. The easy one is fan only while driving. This just requires that Auto and AC be greyed out in the climate screen. The fan speed is the only control active.

This doesn't prevent the heater turning on. So AFAIK, there is no way to actually do "Fan Only" in a Tesla. (Someone please correct if I'm wrong. Seriously, please let me be wrong... I hate this.)

 

[ebmcs03]

This doesn't prevent the heater turning on. So AFAIK, there is no way to actually do "Fan Only" in a Tesla. (Someone please correct if I'm wrong. Seriously, please let me be wrong... I hate this.)

That’s correct. It annoys the heck out of me that the heater turns on and I have to lower the temp setting to about 3-4 degrees below outside temperature to get just “fan” when I turn off the AC.


Sometimes when it’s like low 70s outside I only need fan! But my climate temp is set to 74. So it turns on the heater.

 

[insaneoctane]

I hate this too. Another example of Tesla making me unnecessarily fiddle with the center screen while driving. Having to adjust the climate temperature setting to match the outside temperature to avoid the heater from engaging. Oh and it's a constantly changing target. I just want the fan sometimes!

 

[KarenRei]

Why do you feel the need to do this? If the temperature differential is only a few degrees, the impact on range should be minimal to negligible. I mean, maybe if you were going for a hypermiling run....

 

[insaneoctane]

Why do you feel the need to do this? If the temperature differential is only a few degrees, the impact on range should be minimal to negligible. I mean, maybe if you were going for a hypermiling run....

Because I usually don't want the air heated at all. The wasted energy is insult to injury.
CONTEXT : I live in Southern California....

 

[KarenRei]

Because I usually don't want the air heated at all. The wasted energy is insult to injury.
CONTEXT : I live in Southern California....

If it's colder outside than the temperature you keep the car set to, then by definition, you've told the car that you want the air heated. So the question becomes, why are you lying to your car about what temperature you like it to be inside?

 

[insaneoctane]

If it's colder outside than the temperature you keep the car set to, then by definition, you've told the car that you want the air heated. So the question becomes, why are you lying to your car about what temperature you like it to be inside?

If your post was in jest, please ignore....if not:
It's 72 outside. I set my temperature to 72. Comfortable and no heat. A little while later the temperature outside drops to 69. Now the car is wasting energy with the heater (which I can usually feel). I have to fiddle with things. Rinse and repeat until about ~59 where I finally *might* want some heat. Except for about 1 or 2 months in the year I would simply never want heated air. Maybe heated seats, but not air...

 

[SageBrush]

If your post was in jest, please ignore....if not:
It's 72 outside. I set my temperature to 72. Comfortable and no heat. A little while later the temperature outside drops to 69. Now the car is wasting energy with the heater (which I can usually feel). I have to fiddle with things. Rinse and repeat until about ~59 where I finally *might* want some heat. Except for about 1 or 2 months in the year I would simply never want heated air. Maybe heated seats, but not air...

I set my thermostat to 68-70F to avoid the fiddling.

 

[insaneoctane]

I set my thermostat to 68-70F to avoid the fiddling.

I realize that in my scenario that I could initially set it down to 60, but if things go the other way and get hot enough to need AC that's even more fiddling. The take away is a simple button that says "fan only" that keeps the heater off. Isn't the cabin air heater one of the most power hungry accessories that we "control" (aside from the accelerator) ?

 

[Trevor B]

I set my thermostat to 68-70F to avoid the fiddling.

It is 56 in SFO ... how would that help?

 

[jsmay311]

I realize that in my scenario that I could initially set it down to 60, but if things go the other way and get hot enough to need AC that's even more fiddling. The take away is a simple button that says "fan only" that keeps the heater off. Isn't the cabin air heater one of the most power hungry accessories that we "control" (aside from the accelerator) ?

Exactly. How does it make any sense to have a button to manually control A/C but not a button to manually control heat? Seems to me the dedicated A/C button is an anachronism dating back to when A/C compressors in cars were manually turned on/off via a single button and their control logic wasn't tied to a thermostat or cabin temp at all.

IMO Tesla should just change the A/C button to a "Climate On/Off" or "Fan only" button. That provides the control that I and many others want and I don't see any downside. More fiddling with tiny touchscreen buttons and/or wasting energy when heat/cooling is not wanted is not the right answer.

 

[cella]

Are the climate settings stored in driver profiles? If yes, you could set up a "fan only" profile with temp set to 60 and A/C off, and then easily switch without fiddling with the temperature controls.

I think part of the reason why almost all cars have an A/C button is that it sometimes makes sense to turn on the A/C to remove humidity even if you don't want to cool down the cabin.

 

[nvx1977]

Being judicious with HVAC usage actually pays big dividends for efficiency. Even when the temperature differential is small, like 3 degrees, the resistance heater uses a lot of energy. And in the 69F to 72F example, most people would agree they don't need the heat to feel comfortable. Fan only would be welcome.

Another annoyance: if I need to defrost my windows, it turns on the A/C, which is fine (and the fastest way to defrost), but when I turn off defrost, I want my HVAC settings to go back to what they were. Instead, the A/C is left running. I'm submitting feedback on that one.

 

[beachmiles]

Yet another thread in the long running lack of proper control of the heater.
Can't believe this was not one of the first controls they added seeing that the heater is the largest current draw after propulsion.

 

[Uncle Paul]

Tesla heat is controled by the computer. It adjusts the air going to passenger compartment to achieve the preset temperature the owner indicates.

Currently they do not have a computer over ride switch to allow drivers to select airflow volume independantly of preselected temperature control..

Best work around is to turn off temperature control and open a window. Very energy efficient and controls are right at hand.

 

[SageBrush]

I didn't realize I was going to inflame emotions with this thread.

I live in a 4 season climate, am cold tolerant, and do not mind adapting to the car controls. Outside of winter I set the thermostat to ~ 68 - 70F and turn the AC off. I modulate fan speed for comfort; and if that is not enough I turn the AC on.

In the winter (IIRC) I turn AC on and set the thermostat to ~ 65F. If I am cold I turn on the heat seater.

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My much bigger problem occurs when my wife is also in the car. She fiddles with the HVAC settings. I'm considering reporting her to the NHTSA.