HVAC in cold temps not cutting it

[Chevrltz71]

Took delivery of my P90DL last week here in AK.

I have to say that unless I'm missing something, I'm pretty disappointed in the HVAC performance of this thing so far in cold temps.

First off, it really sucks the power more than I was anticipating. But that's not a concrete complaint. Specifically, when driving in 0-10F temps, which are pretty common around here, the HVAC cannot keep up with defrosting all the windows, much less keeping floor warm. The windshield can stay fairly clear, if you have the floor heat off, however with even just two people in the car (much less 7), all the side windows frost up like crazy! There should be a lot more CFM and BTUs available.

This of course also makes my consumption about 500Wh/mile, so I really only have about 170 miles of usable range.

Thoughts? Did I get a lemon of an HVAC system? I've never read of anyone having trouble keeping their windows clear on here in cold climates.

 

[mgboyes]

Recent v7.0 firmware seems to have a bug in it which makes the AC system really poor/weak at heating. It's not a hardware issue; just software. If you set the temperatures to "HI" does it deliver enough heat for you?

 

[Evbwcaer]

Are you in Range Mode (does your fan go to 11 or 8?)

 

[ToddRLockwood]

As mentioned in the above post, Range Mode could be the likely the culprit because it will limit the fan speed. I've driven my car at below zero F temps many times. I do find that I have to break out of HVAC Auto mode to get the windows to clear completely. Here's my suggestion: open the HVAC settings panel, send air to all three zones (windshield, dashboard, and floor) and turn up the fan speed to 8. Set the temp to 72F. Use these settings until the car is fully warm, then back off the fan speed a bit.

 

[jerry33]

Last winter and the winter before there was plenty of heat. This year with the horrible v7, heat is very limited and sometimes it will blow cold air. v7 should never have come out.

 

[Cyclone]

Chevritz, if you click the "T" logo at the top-center of your 17", what 2.x version of the firmware do you have? If you have anything less than 2.9.12, call and ask your Service Center to push an update to your car because of the known heating shortcomings of the earlier v7 2.x releases. V6.2 (up to 2.5.71) had much better heating performance and 2.9.12 restores it or comes close to it.

 

[qwk]

Updating firmware is a major drawback nowadays, as Tesla's software department isn't very competent. One of the major problems is the California mentality(always sunny and warm), and the fact that most of them drive gasoline cars. Driving a gasoline car and writing software for an electric car doesn't work very good.

 

[mknox]

Last winter and the winter before there was plenty of heat. This year with the horrible v7, heat is very limited and sometimes it will blow cold air. v7 should never have come out.

Yes, v7 "broke" the heat (and a number of other things), but to be fair, I got 2.9.12 the other day and it seems to have improved the heating a LOT. I think any flavor of v7 below 2.9.12 will have poor heating performance.

 

[ArtInCT]

Also, from what I have read, if you push the defrost "button" twice, it turns RED and throws heat into the front and side window defrost mode. Many folks apparently are not aware of this...

 

[mknox]

Also, from what I have read, if you push the defrost "button" twice, it turns RED and throws heat into the front and side window defrost mode. Many folks apparently are not aware of this...

Prior to 2.9.12 even that was not working well. It would set the fan speed to 11 and the heat to HI, but often it was only cold or lukewarm air coming out.

 

[ArtInCT]

Prior to 2.9.12 even that was not working well. It would set the fan speed to 11 and the heat to HI, but often it was only cold or lukewarm air coming out.

I hear you... Recently while at my local SC to discuss something, I was waiting for the service manager in the waiting area. A long time S owner and I got to talking... He was complaining that his front air defroster was only putting out cold air. I told him about the double tap which he did not know about.... We went out to his car with me... Sure enough it worked perfectly. He had the car for 22 months and did not know about this. Just sayin' that perhaps some owners are just not aware of this functionality. In the first mode, from what I understand, no heat is injected in the defroster air however the air conditioner is taking away the humidity. In the second mode (the double tap mode where the insignia turns red) heat is combined into the defrost air flow which is important in the colder climates to defrost the windshield and side windows....

BTW, I do not own an S yet, but picked up this info here on the great TMC forum...!

 

[Chevrltz71]

Great info all! Thank you - I will check on this tonight as I'm drying my sexy ICE GMC 2500 truck today. Lots of heat

I do know that the fan was only going to 8, but I didn't think I was in range mode, but obviously I guess I was? But the air temp coming out at the 8 fan setting was "lukewarm." I'll check my firmware version tonight - doesn't it upload the latest automatically?

 

[Cyclone]

doesn't it upload the latest automatically?

It automatically downloads the latest update at somewhat random intervals determined by HQ. However, it doesn't apply the update automatically. However, the Tesla Service Centers can manually "push" the update to your car, either over the air or via directly plugging into the car's systems. Neither option do they do without cause, but they have a known shortcoming with heat production in the early v7.0 releases and you are in Alaska, so it can easily be understood this would definitely be impacting you and thus, they would make the effort to push the update manually to address your concern.

TL;DR... It will eventually get updates, but fixing active problems takes precedence and you shouldn't wait if you have a version prior to 2.9.12.

 

[Chevrltz71]

Looks like I have 2.7.77 - hopefully this will fix it. Can I "pull" the latest update on my own?

 

[Cyclone]

Looks like I have 2.7.77 - hopefully this will fix it. Can I "pull" the latest update on my own?

Negative, nothing you can do on your end. It's entirely in Tesla's hands. At some point your car will get the update as they stagger them across the fleet. But given the cold, I would just call your Service Center and ask them to make a priority push to your car. About an hour later you should get the notification that you have an update ready to install (assuming your car is on 3G, LTE, or wifi).