Audi e-tron Forum – News, Specs, Pricing & Ownership… banner

1 - 6 of 6 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter · #1 ·
Just got our etron this weekend! Excited but also came with some issues, not sure if we haven’t learned all the features of the car or just poor design.

It seems weird but why do they not allow AC to be turned on while charging? I have other EVs including BMW and Tesla and they all allow that. It’s baking hot here in socal waiting for it to charge!

also having to switch off “ignition “ to open charging port is just nonsense. Any fix or solutions would be greatly appreciate
 

·
Registered
Joined
·
63 Posts
I can turn on the auxiliary AC while charging. It stays on for one hour while charging whereas normally only 30 minutes when not charging. It makes a big difference when it's 105 deg F outside. You should see a prompt on the screen to engage the auxiliary feature.

The MyAudi webpage has a number of helpful videos explaining the feature.
 

·
Registered
2019 e-tron prestige
Joined
·
246 Posts
Out of curiosity, why does Auxiliary AC even exist as opposed to just the standard AC control? This must be a holdover from the gasoline platform but I still don’t quite understand it.
 

·
Registered
Joined
·
773 Posts
The term "AC" I think is very tricky. In looking through the technical manual, it's easy to confuse the classic AC (as in air cooling system) and the AC (air conditioning as applied to the heat pump). The heat pump warms the cabin by scavanging up all the waste heat generated by the battery, motors, electronics and circulates the AC fluid to heating coils that will warm up the air. If you are stationary, there is no heat for the heat pump to work with, and so the car has to rely on the auxiliary resistive heaters. (For cooling, I think the system uses the traditional AC system when the car is turned off. Why? I'm not sure, but the heat pump may be more geared toward removing heat from the battery/electronics/drive train, so having the "auxiliary" AC may let Audi optimize for that. Also, the car for other reasons--read below--needs a traditional AC system, so why not use it?). As best as I can tell, the "AC" on the Cabin Conditioning Display refers to Air Cooling in the traditional sense. If the ambient temp is below what you want, the car pulls in air from the outside, the traditional AC (Air Cooling) cools the air down to dehumidify it and then passes it to the heat pump system (which is using an AC in reverse) to heat the air up to the temp you desire. The preceding is what happens if 1) the Cabin Conditioning system is turned "ON" and 2) the AC button is turned ON or on ECO setting. If the ambient air is dry enough, you can turn the AC "OFF" and the heat pump portion will continue to work to heat that air up. In cold weather, you can save a few electrons by switching off the AC, but if your windows start to fog up you will need to turn the AC back ON or in ECO mode. To cool the cabin, the AC needs to be turned on, since that is the only way to get the ambient air down below cabin temp, as well as dehumidify it. Then, the heat pump adds a touch of heat to get it to where you want it. (I would think the heat pump would also have the ability to transfer the heat to somewhere besides the cabin to help it manage the battery, electronic, drive train temp, but have not delved into that at all. So, I don't know if the car has the ability to do some cabin cooling using the heat pump in reverse.)

So, in short (?), while the heat pump theoretically can both heat and cool, there are situations where resistive heaters and traditional AC systems are needed. Audi, reasonably then, just makes the best use of all three. The overall advantages are that the heat pump 1) uses 1/3 of the energy needed by resistive heaters to condition the cabin, and, 2) helps with thermal management of the battery, electronics, and drive train.
 

·
Registered
2019 e-tron prestige
Joined
·
246 Posts
Thanks! This makes sense, but from a user perspective it sure is convoluted. I hope they put more focus into making their user interfaces intuitive. The last thing I want to do while driving, or on a long trip is pull out the manual or troubleshoot climate controls!
 
1 - 6 of 6 Posts
Top