Dear Rivian Engineers who worked on the Air Conditioning

[Si.LE.R1S]

That would explain why pet mode cools well - all cooling is going to the cabin, most likely none to the battery and motors.

Hmm. I wonder if Pet mode recruits the rear compressor (overrides seat belt/seat position requirement - seems to make sense for a pet).

I didn’t do any “scientific testing” but my S seemed to cool faster with the 3rd row buckled and fan on 4, with front sync set to LO/recirc (after a brief windows down to release warm cabin air). For reference, I live in Hades…err Vegas.

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[Whale Blubber]

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.

Mine doesn't go over 2 much. After 800 miles in ATX around town (15-30 minute trips primarily), I'm averaged at 1.8. No conserve, just a few launches, mostly just AP / high regen / AC on 71 degrees -- but I drive 80 on the highway when it's open enough to let me.

As to cooling, I'm doing fine so far in Austin despite pretty insane temps. But I leave it outside uncovered rarely. Usually it's in a garage, whether at work or home.

 

[Winger]

Last week the cabin temp on the app was 113F so I turned on the a/c remotely and by the time I exited the elevator at work and got into the truck it was in the seventies....didn't have a chance to document times and temps so here is are the pics from today: 93F to 68F in four minutes. AC compressor is quite loud outside the car until I settle in and put it in drive (I keep it on LO and fan at two) at which point it quiets down substantially. From my experience, if your car isn't cooling the cabin in 5 minutes, something is wrong either mechanically or from an operator point of view. Here's the pics.

 

[rpmtexas]

Hmm. I wonder if Pet mode recruits the rear compressor (overrides seat belt/seat position requirement - seems to make sense for a pet).

I didn’t do any “scientific testing” but my S seemed to cool faster with the 3rd row buckled and fan on 4, with front sync set to LO/recirc (after a brief windows down to release warm cabin air). For reference, I live in Hades…err Vegas.
[/QUOTE

Mine doesn't go over 2 much. After 800 miles in ATX around town (15-30 minute trips primarily), I'm averaged at 1.8. No conserve, just a few launches, mostly just AP / high regen / AC on 71 degrees -- but I drive 80 on the highway when it's open enough to let me.

As to cooling, I'm doing fine so far in Austin despite pretty insane temps. But I leave it outside uncovered rarely. Usually it's in a garage, whether at work or home.

I’m in ATX too. You’re definitely having a different experience, but maybe because you’re not in the sun. Does your S turn your garage at home into and oven when you charge it? Our garage gets very hot when the truck is in there charging. We also have an eTron and it doesn’t heat up the garage.

 

[andisimose]

Hmm. I wonder if Pet mode recruits the rear compressor (overrides seat belt/seat position requirement - seems to make sense for a pet).

I didn’t do any “scientific testing” but my S seemed to cool faster with the 3rd row buckled and fan on 4, with front sync set to LO/recirc (after a brief windows down to release warm cabin air). For reference, I live in Hades…err Vegas.

I tested today. My rear seats are folded down so no buckles. Pet mode did in fact turn the 3rd row vents on. They were blowing somewhat cold air as I walked away

 

[Zoidz]

Just throwing some additional information into the mix - see below. The Rivian EPA document date 5/26/23 says there are "solar load sensors" as part of the cooling system logic..... ?

08.06.03 Climate control system logic
HVAC software has multiple modes which can be selected based on user preference:
• In Manual Mode, the user has complete control on blower speed, temperature, and airflow
distribution to face or feet. Recirculation of air is also manually controlled by the user.
• In Auto mode, the software provides adequate heating and cooling requests to control the
breathing temperature of both driver and passenger to the requested setpoint. In this mode, the
airflow distribution and the blower speeds are automatically selected to maintain the desired
temperature from the screen. The software estimates the breathing temperature of individual
passenger based on airflow through ducts, In-Cabin sensors, external ambient temperature
sensors, and solar load sensors. Recirculation of air inside the cabin is automatically selected
based on humidity level inside the cabin.
• Additionally, defrost or demist mode is provided to the user for a clear view while driving.
During defog mode, the software supplies conditioned air towards the windshield based on the
dew point calculation. If the desired mode is Defrost, the PTC (Positive Temperature
Coefficient) heater blows hot air towards the windshield to clear frost

 

[Zoidz]

To illustrate how complex the Rivian cooling system is, here's a diagram from the patent. The patent has lots of interesting information on how it works (if you are a engineering, systems, or car geek ) with the assumption that it is actually built similar to the patent.

 

[Leonbmx]

So, last weekend I was doing some errands, it was upper 80's outside and I had the pup in the back, so I set the AC to "LO" and did hear some more noise than usual from the front, but I figured that was normal, as I had never used "LO" before.

Everything was working fine otherwise, cabin got cool quick and we resumed our journey.

Fast FWD a few hours, I was going to take the pup out to the beach, so I wanted to precool the truck and upon entering, the AC would not turn on. I would press the on button, but it would immediately turn back off again. Interestingly this includes the seat coolers, and window defrosters.

Tried soft reset followed by a hard reset and both did not remedy the situation. But it did result in a fancy new error icon on the dash. Looks like a windshield defroster? (see pic)

Called it in and after some more troubleshooting (basically resetting again) I got an SC apt for 8/30.

BUT, this is not the end of the story... This was all on a Sunday, so I plugged the truck in to charge for my commute. Come Monday morning, the truck had been charging for more than 9hrs and only added 24 miles for range!!

Reported this to Rivian as a separate issue, only to get confirmation that these are, as mentioned in this thread earlier, related systems and with a failure of the AC system, the battery cooling system is also impacted, effectively throttling the charge rate down to a "safe" level. With temps in the high 80's, that results in a 1kWh charge rate, going up slightly at night.

This is not a sustainable charge rate for my commute, and with the cooling out, fast charging is a definite no-go.

Even with all of this, currently the SC service date has not moved.

 

[R1TS]

I tested today. My rear seats are folded down so no buckles. Pet mode did in fact turn the 3rd row vents on. They were blowing somewhat cold air as I walked away

The third row vent is just recirculating air from intake in the trunk, just above the air compressor. It’s not connected to the main HVAC at all.

 

[fromSf]

So, last weekend I was doing some errands, it was upper 80's outside and I had the pup in the back, so I set the AC to "LO" and did hear some more noise than usual from the front, but I figured that was normal, as I had never used "LO" before.

Everything was working fine otherwise, cabin got cool quick and we resumed our journey.

Fast FWD a few hours, I was going to take the pup out to the beach, so I wanted to precool the truck and upon entering, the AC would not turn on. I would press the on button, but it would immediately turn back off again. Interestingly this includes the seat coolers, and window defrosters.

Tried soft reset followed by a hard reset and both did not remedy the situation. But it did result in a fancy new error icon on the dash. Looks like a windshield defroster? (see pic)

Called it in and after some more troubleshooting (basically resetting again) I got an SC apt for 8/30.

BUT, this is not the end of the story... This was all on a Sunday, so I plugged the truck in to charge for my commute. Come Monday morning, the truck had been charging for more than 9hrs and only added 24 miles for range!!

Reported this to Rivian as a separate issue, only to get confirmation that these are, as mentioned in this thread earlier, related systems and with a failure of the AC system, the battery cooling system is also impacted, effectively throttling the charge rate down to a "safe" level. With temps in the high 80's, that results in a 1kWh charge rate, going up slightly at night.

This is not a sustainable charge rate for my commute, and with the cooling out, fast charging is a definite no-go.

Even with all of this, currently the SC service date has not moved.

Rivian needs to address the HVAC issue quickly. In my case, I am not able to drive the car if the temperatures are above 90 degrees Fahrenheit. There is absolutely no cooling, and the compressor makes crazy noise. I have been calling customer service every other day, but it has been of no use. My appointment is still only in November 22nd.

By November, the temperatures will be below 80 degrees Fahrenheit. I am worried that the service center will say that everything is normal and return the car to me as-is, just as they did three weeks ago. Rivian cannot deny the HVAC issue any longer. I am seriously considering contacting a few media outlets to get some attention.

 

[SoCal Rob]

The third row vent is just recirculating air from intake in the trunk, just above the air compressor. It’s not connected to the main HVAC at all.

I thought that, too, but @redantpile showed the cooling lines feeding the rear blower assembly here:https://www.rivianforums.com/forum/...ked-on-the-air-conditioning.17267/post-378365

I’m glad to be wrong about it! Now, if Rivian would change the icons when those vents are actively cooled to show cooled air (blue snowflake) rather than just blowing air (gray wavy lines) it would probably help us understand what the third row is doing at any given time.

 

[jpmc86]

The third row vent is just recirculating air from intake in the trunk, just above the air compressor. It’s not connected to the main HVAC at all.

this is not accurate. It is indeed shared with the main compressor and HVAC.

 

[nomis]

Not sure if it was mentioned already, but air speeds across the condensor when vehicle is at speed vs just the condensor fans when vehicle is stationary is a night and day difference even with 100+ outside temps. The vent temperatures while the car is moving is way cooler than sitting at a red light, but that is normal operation with any vehicle.
I would highly consider getting some tint on all the windows if you haven't already. They help a ton in cooling down the cabin. I have 5% ceramic tint on everywhere except the front, 10% for front windows and a 80% UV film for the front windshield. My tint guy measured the tint for the glass roof. The meter couldn't get an accurate read, but it was <3%.

 

[gregtay]

I've got some experience with sizing of refrigeration systems which is really what we are dealing with here. Systems are designed as, well, a "balanced system". If the problem is that the system is properly designed but undersized for the BTU load (such as underestimating the heat load created by the greenhouse roof in the R1S at 110 degrees ambient), just Increasing the compressor size likely won't fix this type of problem. All of the components - lines sizes (tubing), evaporator and condensor coils, thermal expansion valve or capillary tube, etc. all need to be resized. The only thing a new compressor would fix is if they somehow undersized it in the original design, but since it works fine for many people at or under 100 degrees, I think it's an overall system BTU capacity issue. The other possibility is that it was designed correctly but an OEM is not delivering components to spec.

If the system was "undersized" then wouldn't the air coming out of the vents at least be ice cold... but simply not enough cold air to lower the cabin temp? The issue I have on 115 degree day is that the air coming out of the vents is "cool" but not "ice cold". Start my Audi, X5 or Escalade and within a min or so the air is ice cold coming out of the vents (still takes a few mins to fully cool the cabin).

 

[txtravwill]

Love getting into the truck and days like this and it blows hot air for 10 mins!

Worst AC ever. May have to get rid of it just due to AC.

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