Dear Rivian Engineers who worked on the Air Conditioning

[Ripped]

Haven't read through this thread, but has Munro taking this system apart yet and critiqued it?

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[Cactus]

Haven't read through this thread, but has Munro taking this system apart yet and critiqued it?

Motors yes, but I don't think he's pulled apart the AC system. He's in Michigan anyway. AC system works fine if your hottest temp is 93°F. LOL.

 

[HaveBlue]

I think it's the moon roof. Basically a big atrium. Horizontal glass is brutal which is why cars have a sliding shade on the small moon roof. The flat windshield on a Prius creates a huge oven on the expansive dash. I'll bet shading that would make a big difference.

 

[Zoidz]

Motors yes, but I don't think he's pulled apart the AC system. He's in Michigan anyway. AC system works fine if your hottest temp is 93°F. LOL.

100, lol. In Delaware I have 5-10 minute cooling to 72 with temperatures of 100 degrees.

 

[Zoidz]

I think it's the moon roof. Basically a big atrium. Horizontal glass is brutal which is why cars have a sliding shade on the small moon roof. The flat windshield on a Prius creates a huge oven on the expansive dash. I'll bet shading that would make a big difference.

Agree, if Rivian had a factory shade or had not installed a huge greenhouse roof, I don't think this would be an issue at all.

 

[Cactus]

If the requirements of the AC system are to cool the cabin AND to keep the battery cool within operating temps, it should be robust enough to do those things even under extreme conditions, yes?
The system should be engineered so that cabin temps are not sacrificed to cool the battery. Yes, I understand that if the battery overheats, thermal runaway is very very bad.

 

[WorldComposting]

Went to Williamsburg, VA this past weekend and even with leaving the car in the parking lot in the sun with it being 95+ degrees outside I had zero issues cooling down the car. Car was saying 100 degrees outside and the interior was registered 135 via the app when we started cooling it down. With 6 people in the car interior cooled down in a couple minutes while set to 71 degrees. If it gets over 100 here in MD I'll be sure to test it but so far I'm not seeing any issues cooling down my R1S.

Biggest issue was the outside of the car was very hot. The handles on the drivers side in full sun were hard to touch which I never thought would be an issue.

 

[fromSf]

I live in the Bay Area and am really struggling with my R1S. I can't take the vehicle out if the temperature is above 85 degrees Fahrenheit. First, the compressor noise is super loud, like a leaf blower, and there is no cooling effect (even with the windows and roof tinted). Three weeks ago, I had an appointment at the SJC service center, but they didn't do anything. They simply returned the car, stating that they were waiting for further instructions from engineers and that I would be at the top of the list when they heard any updates. The compressor noise has gotten worse and has started to vibrate the brake and gas pedals, which is hurting my legs. I complained to Rivian and shared all the videos of the leaf blower-like noise. I have an appointment at the SF service center on November 22nd. I requested an earlier appointment, but I'm on the waitlist.

Tomorrow, a Hansshow shade will be delivered. I'm hoping that this will help in the meantime. For the rear panoramic roof, I bought a shade that doesn't fit perfectly, but it's a temporary workaround. It covers 95% of the roof.

https://www.amazon.com/dp/B086RFDBZW?psc=1&ref=ppx_yo2ov_dt_b_product_details

Here is a sample compressor noise video:

 

[Dark-Fx]

Michigan

I took this on a 90 degree day here earlier in the year. Not totally sure how long it was sitting since my wife started the R1S, but her response was "oh, I didn't think it would work that fast". If your cars aren't keeping up at higher temps to get the cabin comfortable, then there is something wrong with them. It could be the higher outside temps are causing pressure issues due to the amount of refrigerant, but it should still work.

 

[rpmtexas]

Yes, for sure the cooling system spends energy to cool the batteries. Here is my post from a related thread.

I did an experiment with my R1S last week.
Background:
Many on this forum have noticed a dramatic drop in efficiency (mi/kwh) when getting in a hot or warm R1S and running the AC while it does its "full throttle weed wacker" impression to make the cabin cool, often unsuccessfully. My R1S goes from a normal 2.2+ mi/kwhr to <1.7 mi/kwh. I have posted this efficiency in another thread.

Methods:
I decided NOT to turn on the AC during my drive home from work (initial cabin temp >125°F) and simply drive ~12 miles with vents blowing and windows cracked about 2 inches WITHOUT the AC on. Then take a picture of the energy graph when arriving home.

Results:
Besides being pretty sweaty by the time I got home, I noticed that the mi/kwh graph does essentially the same thing as when the AC is ON during the same drive home. Efficiency takes a big hit for the first ~5 miles, then gradually gets better.

Discussion:
This leads me to suspect that the vehicle might be trying to cool the battery pack, and that the AC compressor (despite all the racket) doesn't use a lot of power.

Wow. My efficiency is never that high. Usually around 1.5.

 

[Southern R1S]

Wow. My efficiency is never that high. Usually around 1.5.

Wow, that seems low. My average economy over the first ~3,700 miles on my R1S (20" AT tires) is 2.29.

Average outdoor temps during that period are probably in the 85-95 range and somewhere in the ballpark of 95% in-town driving (around 45mph) and 5% interstate. Always in All-Purpose Mode with standard regen except for maybe 50 miles of towing. Never touched Conserve mode due to tire wear concerns. Roughly ~30 launches during that period because, well, it's a new toy.

I've never gone into Conserve mode over tire wear concerns.

 

[rpmtexas]

Wow, that seems low. My average economy over the first ~3,700 miles on my R1S (20" AT tires) is 2.29.

Average outdoor temps during that period are probably in the 85-95 range and somewhere in the ballpark of 95% in-town driving (around 45mph) and 5% interstate. Always in All-Purpose Mode with standard regen except for maybe 50 miles of towing. Never touched Conserve mode due to tire wear concerns. Roughly ~30 launches during that period because, well, it's a new toy.

I've never gone into Conserve mode over tire wear concerns.

Yeah, I’m thinking we may have a problem. It almost NEVER goes above 2. Not launching, driving in all purpose mode with standard regen.

 

[Southern R1S]

Yeah, I’m thinking we may have a problem. It almost NEVER goes above 2. Not launching, driving in all purpose mode with standard regen.

Definitely think it's worth having service take a look. Even when I first got it and was launching like crazy I was consistently seeing above 2.0 average so something definitely seems off. I admittedly drive it a lot more conservatively now that some of the new has worn off (but still gun it a few times a week since there's no reason to drive a super truck if you're not going to take advantage of the power), but any average under 2.0 seems very, very low from my experience with my R1S.

Hopefully service can run some deeper diagnostics & figure something out for you on this.

 

[rpmtexas]

So I just went out with the thermometer again. My AC system definitely cannot cool the air much when the blower is on high. There is actually a 15 degree difference between the air temp in low (air at vents is 44.7 degrees) and high (59.9). That seems like a lot to me. I went back and forth multiple times and the numbers settled to consistent temp within .3 degrees. Changing the temp setting (Lo, 62, 68) made no difference in air temp exiting vents (which makes sense). Ambient temp was 89.1 in the shade. Cabin temp was 101.2 at entry into the vehicle. Vehicle said outside temp was 104 and cabin temp was 108. So the vehicle thermometers are also not positioned in a way to give accurate readings…

 

[rpmtexas]

Definitely think it's worth having service take a look. Even when I first got it and was launching like crazy I was consistently seeing above 2.0 average so something definitely seems off. I admittedly drive it a lot more conservatively now that some of the new has worn off (but still gun it a few times a week since there's no reason to drive a super truck if you're not going to take advantage of the power), but any average under 2.0 seems very, very low from my experience with my R1S.

Hopefully service can run some deeper diagnostics & figure something out for you on this.

Thanks! Hopefully they can figure it out. For a few days efficiency was even around 1.25. Maybe I have a ghost boat attached to it ?

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