HVAC User Interface and Efficiency

duessell

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User Interface:
I find the user interface for the HVAC a bit confusing and counterintuitive at times. See the two images below. In the first, I show that the interior temp was set to 71 degrees and the vents show red heating lines. In the other, I show the interior temp set to 70 degrees and the vents switch to snowflakes. It was 41 degrees outside and it definitely was not running the AC. Are these displays just based on the temperature setting? Would seem more intuitive to me if they were based on what the HVAC system is actually doing at that point.

Efficiency:
We had mild weather for a few weeks here (until about a week ago) and I ran for a week with the HVAC on auto even though zero conditioning other than vent was necessary. The AC seemed to run unnecessarily and I averaged 1.9-2.0 miles/kWh, about the same as hotter times when the AC was needed. Then for a couple weeks, I ran with just the vent and forced the AC/heat to be off and saw my average efficiency go up to 2.1-2.3 miles/kWh. Sort of makes me wonder if the AC compressor is working a lot harder than it needs to.

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mindstormsguy

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It might have actually turned on AC if it thought the cabin needed to be cooled a degree. 🤷‍♂️

There are definitely some quirks on the hvac on these trucks though.
 

Frisbie

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My R1T does the same thing. It can be 41 outside and the temperature inside set at 70. The air conditioning comes on. Change the temperature to 71 and the heat will come on. During the summer in Phoenix it was 115 outside. The inside temperature set at 80 and the heat came on. There is something really wrong with the HVAC. I have no idea as to whether it is a software problem or the temperature sensors are not positioned correctly but it needs to be fixed.
 

Rousie13

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I think the pictures (snowflake/heat lines) are purely based on set temperature and not what the HVAC is actually doing. I think they just have them set at 70/71F arbitrarily. That does seem weird though.
 

gombater

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got the same issue and was about to post similar pics - as it has finally gotten cold enough to want/need heat, the HVAC system is not very intuitive - if it's 40 deg out and I have auto set to 68, it's blowing cold air and feet are freezing. will set to 71 and see if any difference. you would think it should actually show what it is doing, and for my situation, I think it is - I have never seen the heating icon on the vents, as I have set auto to 68 and not moved it since. cabin does not feel 68 though especially at the lower vents. seat heating is great though - anything over 1 dot and I feel like I am being cooked.
 


Rousie13

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got the same issue and was about to post similar pics - as it has finally gotten cold enough to want/need heat, the HVAC system is not very intuitive - if it's 40 deg out and I have auto set to 68, it's blowing cold air and feet are freezing. will set to 71 and see if any difference. you would think it should actually show what it is doing, and for my situation, I think it is - I have never seen the heating icon on the vents, as I have set auto to 68 and not moved it since. cabin does not feel 68 though especially at the lower vents. seat heating is great though - anything over 1 dot and I feel like I am being cooked.
I have my temp set to 67 and I was confused the other day as well by the pictures. I put a thermometer on the storage tray on the floor and it was reading 65-66 when it was in the low 40s/upper 30s outside.
 

madgrey

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Yes, this system needs some work.

This evening, I drove my family to dinner, around 20 miles with outside temps in the mid forties. With the system set at 72 degrees F AUTO, it seemed very cold in the vehicle during most of the trip, even after turning the temp up to 75. In my other vehicles, I run at 68-69 F because I tend to like colder interior temps. With clear skies and sun, it was fairly bright outside.

The system acted differnetly on the way home from dinner. With temps dropping and the sun set, I set it back to 72 AUTO and it was almost too warm all the way back home.

I feel like the system is intuitive in auto mode but it needs to work consistently before I'm convinced.
 

JamesPolk24

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Keeping the R1T set to 70°F AUTO, the cabin only gets to 55°F (it displays current cabin temp in app) -- Don't understand the logic on this truck. It's obviously not just my experience either.

EDIT: Ambient at 28°
 
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duessell

duessell

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I've also noticed that the HVAC tends to stay on for a while after existing the vehicle. Likewise, it turns on and stays on for a while after I just open the door from outside to grab something and close it without ever entering the vehicle.

Another curiosity: this morning, the HVAC was still running with noone in the car and the doors closed and windows up. When I went to retrieve something from the gear tunnel, I noticed a significant amount of air blowing out of the latch for the gear tunnel door. (The passthrough was also closed.)

Interesting, while writing this post in my truck, I had auto off and set the temp to 75 just to see if it would warm up. Cabin got up to 77 (as shown in the app) before I turned it down to 70.

PXL_20221119_163302986~2.jpg
 

Dark-Fx

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I've also noticed that the HVAC tends to stay on for a while after existing the vehicle. Likewise, it turns on and stays on for a while after I just open the door from outside to grab something and close it without ever entering the vehicle.

Another curiosity: this morning, the HVAC was still running with noone in the car and the doors closed and windows up. When I went to retrieve something from the gear tunnel, I noticed a significant amount of air blowing out of the latch for the gear tunnel door. (The passthrough was also closed.)

Interesting, while writing this post in my truck, I had auto off and set the temp to 75 just to see if it would warm up. Cabin got up to 77 (as shown in the app) before I turned it down to 70.

PXL_20221119_163302986~2.jpg
Behind the seats is basically open into the top of the gear tunnel.
 

 
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