Dear Rivian Engineers who worked on the Air Conditioning

[Deadfish]

I’m curious what previous cars you’ve had that had some sort of solar / IR reduction from the factory on the side windows.

As far as I know, only Jaguar and Mercedes have offered that in the recent past.

Saabs(for 20+years), Volvo for sure, I'm pretty sure my GMC, ford and Dodge had it too. (not full tint, but some type of solar / IR reduction in the windshield).

The other very sunny day I went from the Rivian to my friend's 5 yr old Kia niro - it has some kind of tint/IR. You can feel it when you drive from shade to sun. It's not like sticking your arm in the oven. (I really noticed because I had a bit of a sun burn)

I think they all had IR to be technical:

Solar Glass Infrared Windshield Keeps Cars Cool | Safelite

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[Cactus]

How/where can I see my efficiency with and without the AC going?

Hold down the left or right button on the left side of the steering wheel to toggle thru map, efficiency and tire pressure, which will show on the left side of the Driver display. When you get to efficiency (mi/kwh) turn the AC off for 15 mins and drive a route. Take note of the efficiency in mi/kwh after 15 mins with AC off. Then do the same thing (at same ambient temp) with AC on at your chosen interior temp.

I would wonder what efficiency is when AC is at low vs. when it is at 72F, for example.

My AC (as well as others on this forum) is mis-behaving such that the compressor winds up to full throttle weed whacker without blowing cold air when the cabin is really hot (probably >110F). Efficiency (mi/kwh) tanks when this happens; mine goes from 2.2 to 1.68 mi/kwh.
When the compressor has worked itself into a frenzy, @Craigins figured out that if one toggles off the AC for ~30 seconds, then back on, the compressor is quieter and blows cooler air and efficiency improves.
Hence the title of this Thread: "Dear Rivian Engineers who worked on AC" I know they can do better!

 

[JohnB R1T]

How/where can I see my efficiency with and without the AC going?

Toggle the driver's screen using the button to the left of the left side scroll wheel...it switches between efficiency, tire pressure, and map

 

[sub]

When the compressor has worked itself into a frenzy, @Craigins figured out that if one toggles off the AC for ~30 seconds, then back on, the compressor is quieter and blows cooler air and efficiency improves.
Hence the title of this Thread: "Dear Rivian Engineers who worked on AC" I know they can do better!

That actually sounds like it could be a hardware issue. It sounds like what would happen air got into the coolant pump.

The pump is designed for liquid so it can't push the air out. The computer sees the temperature going up and up so it tells the compressor to run faster and faster, but it does no good because the coolant pump is not pumping anything.

When you turn the system off, the air bubble can float out on its own allowing the pump and therefore the AC to work again.

If this was happening to me, I would look for coolant leaks, and would try flushing the coolant system to remove any bubbles.

 

[zymolysis]

I get that the temp setpoints may not be accurate, but if the interior temp is 105F (for example), the AC unit works just as hard to satisfy the thermostat set for 72 (until it gets to what the thermostat believes is 72) as it does when the temp is set to 60F (until it gets to what the thermostat believes is 60).

Or is there some fuzzy logic/AI in AC compressors and thermostats now?

None-the-less, I will try setting the temp to 65F or 60F to see if it cools better.

The recent OTA might have addressed issues with temperature control (I think I saw something in the notes about that), but temperature control has been an issue that I've noticed. I don't know where the sensors are, or what the logic is, but it hasn't worked the way I think it ought to. Even before it got hot, a degree or two difference in the set temp could make a dramatic difference in the operation of A/C. It appeared to me to be more control (or software) issue, than a cooling capability issue.

 

[zymolysis]

I really wish the glass roof had been optional. When purchasing the R1T I asked if it could come without the glass roof and was told no. From prior experience with automotive glass roofs I knew it was going to be a problem in the Arizona summer heat. I have installed a roof sun screen which helps but there is still a heat load radiating through which the A/C struggles to cool. The HVAC system, summer or winter, is simply substandard. Running it on manual seems to help some.

Yeah, I'm with you there. All of us that didn't want a glass roof are subsidizing those that did.
I recommend a reflective, insulated sunscreen - as opposed to a basic fabric or mesh sunscreen. You want to reflect as much light as possible, and then trap and insulate the heat from the glass, to limit the heat getting into the cabin.

 

[Kazumodo]

Hold down the left or right button on the left side of the steering wheel to toggle thru map, efficiency and tire pressure, which will show on the left side of the Driver display. When you get to efficiency (mi/kwh) turn the AC off for 15 mins and drive a route. Take note of the efficiency in mi/kwh after 15 mins with AC off. Then do the same thing (at same ambient temp) with AC on at your chosen interior temp.

I would wonder what efficiency is when AC is at low vs. when it is at 72F, for example.

My AC (as well as others on this forum) is mis-behaving such that the compressor winds up to full throttle weed whacker without blowing cold air when the cabin is really hot (probably >110F). Efficiency (mi/kwh) tanks when this happens; mine goes from 2.2 to 1.68 mi/kwh.
When the compressor has worked itself into a frenzy, @Craigins figured out that if one toggles off the AC for ~30 seconds, then back on, the compressor is quieter and blows cooler air and efficiency improves.
Hence the title of this Thread: "Dear Rivian Engineers who worked on AC" I know they can do better!

I'm going to have to try this tomorrow. This had been driving me crazy!!! Car gets cool but not cold air but nothing like I would expect and vibrates the vehicle pedal and floor. I had just assumed it just have been trying to condition the battery instead of blowing cold air in cabin

 

[Zoidz]

That actually sounds like it could be a hardware issue. It sounds like what would happen air got into the coolant pump.

The pump is designed for liquid so it can't push the air out. The computer sees the temperature going up and up so it tells the compressor to run faster and faster, but it does no good because the coolant pump is not pumping anything.

When you turn the system off, the air bubble can float out on its own allowing the pump and therefore the AC to work again.

If this was happening to me, I would look for coolant leaks, and would try flushing the coolant system to remove any bubbles.

Sorry, that’s incorrect.

Air conditioning compressors are designed to take low pressure refrigerant vapor (not liquid) in on the suction side, compress it to high pressure/temperature vapor and move it through the condensor coil. It condenses into liquid in the condenser coil due to air blowing through the condensor coil which removes heat, making the vapor condense.

Once cooled and condensed into liquid, it travels to the expansion valve and to the evaporator coil where it expands into vapor while absorbing heat, thereby creating cool air, and heads back to the suction of the compressor as vapor. That’s known as the refrigeration cycle. All it really does is transfer heat.

Refrigerant in liquid state on the suction side of the compressor will destroy the compressor - refrigerant in liquid form (really any liquid) is not compressible. It’s known as slugging the compressor and it’s a bad thing. If an air bubble does get in a refrigeration system it will get trapped in the condenser coil.

if an air bubble forms in a refrigeration system, it usually gets trapped in the condenser.

 

[elektrode]

The efficiency just tanks.

Yeah who knew cooling this thing was almost as bad as towing a 5000lb boat.

 

[Cactus]

Yeah who knew cooling this thing was almost as bad as towing a 5000lb boat.

Yep. This same thing happened to me today, AGAIN. To remedy, I turned off AC for 2 mins, then back on and efficiency increased to 2.14 mi/kwh. I was driving in stop and go traffic no faster than 45 mph, and certainly no launches. LOL. AC never really got cool by the time I got home 15 mins later.

Here's what's tragic. I have a new R1S (cool vehicle, right?) and I am driving my old 2014 Tesla Model S because it gets cool within a couple mins after leaving work. In the R1S, I sweat like a boxer all the way home. I was going to sell the Model S, because I want the Rivian to replace it.

Service center is so busy fixing poorly manufactured vehicles that my appointment is a month away! Grrr.

 

[Si.LE.R1S]

Yep. This same thing happened to me today, AGAIN. To remedy, I turned off AC for 2 mins, then back on and efficiency increased to 2.14 mi/kwh. I was driving in stop and go traffic no faster than 45 mph, and certainly no launches. LOL. AC never really got cool by the time I got home 15 mins later.

Here's what's tragic. I have a new R1S (cool vehicle, right?) and I am driving my old 2014 Tesla Model S because it gets cool within a couple mins after leaving work. In the R1S, I sweat like a boxer all the way home. I was going to sell the Model S, because I want the Rivian to replace it.

Service center is so busy fixing poorly manufactured vehicles that my appointment is a month away! Grrr.

@Cactus

Your SC should have some capacity for “urgent” issues - these are reserved where the situations are considered potentially unsafe. When I spoke to the phone advisor, I told them the car was uncomfortable but that I could tolerate for a commute home. But I also informed them that I would not feel safe taking it on our planned family road trip to Cali from Vegas, across the desert. That struck a chord. I got an appointment the same week. Truck is in the shop now and I’m waiting to hear what they find. Advisor is betting on refrigerant charge/leak. He also reiterated that when the system goes weed whacker, it is likely prioritizing battery cooling over cabin. Toggling sometimes helps, but I’m nervous this is bypassing an important mechanism to keep the battery healthy. ??‍

As an aside, to document the cooling issue, I took periodic screen saves of the ambient temp and pre-condition set temp over a 30 minute period (140 to 95 degrees). I then put the car in pet mode for 30 minutes and took some screen saves (shows current ambient and set temp). Never dipped below 90 sitting in the Vegas heat. Definitely meets “unsafe” criteria IMO.

Absolutely love the truck outside of this issue. I’m fact I just got a set of ATs and can’t wait to do some real adventuring after the heat subsides! I tend to be an early adopter, so I accept there’s gonna be some hiccups. I’m confident that Rivian will work out the kinks.

 

[Craigins]

He also reiterated that when the system goes weed whacker, it is likely prioritizing battery cooling over cabin. Toggling sometimes helps, but I’m nervous this is bypassing an important mechanism to keep the battery healthy. ??‍

Just a heads up, this is faulty logic.

If the battery needs to be cooled, then the truck cools the battery. The state of the cabin climate control has no affect on the behavior.

If the truck can only heat/cool the battery when the occupants have the climate controls running then the system is essentially worthless. For example I do not use the heat in the winter.

 

[Si.LE.R1S]

Yep. This same thing happened to me today, AGAIN. To remedy, I turned off AC for 2 mins, then back on and efficiency increased to 2.14 mi/kwh. I was driving in stop and go traffic no faster than 45 mph, and certainly no launches. LOL. AC never really got cool by the time I got home 15 mins later.

Here's what's tragic. I have a new R1S (cool vehicle, right?) and I am driving my old 2014 Tesla Model S because it gets cool within a couple mins after leaving work. In the R1S, I sweat like a boxer all the way home. I was going to sell the Model S, because I want the Rivian to replace it.

Service center is so busy fixing poorly manufactured vehicles that my appointment is a month away! Grrr.

@Cactus

Your SC should have some capacity for “urgent” issues - these are reserved where the situations are considered potentially unsafe. When I spoke to the phone advisor, I told them the car was uncomfortable but that I could tolerate for a commute home. But I also informed them that I would not feel safe taking it on our planned family road trip to Cali from Vegas, across the desert. That struck a chord. I got an appointment the same week. Truck is in the shop now and I’m waiting to hear what they find. Advisor is betting on refrigerant charge/leak. He also reiterated that when the system goes weed whacker, it is likely prioritizing battery cooling over cabin. Toggling sometimes helps, but I’m nervous this isbypassing an important mechanism to keep the battery healthy. ??‍

As an aside, to document the cooling issue, I took periodic screen saves of the ambient temp and pre-condition set temp over a 30 minute period (140 to 95 degrees). I then put the car in pet mode for 30 minutes and took some screen saves (shows current ambient and set temp). Never dipped below 90 sitting in the Vegas heat. Definitely meets “unsafe” criteria IMO.

Absolutely love the truck outside of this issue. I’m fact I just got a set of ATs and can’t wait to do some real adventuring after the heat subsides! I tend to be an early adopter, so I accept there’s gonna be some hiccups. I’m confident that Rivian will work out the kinks.

Just a heads up, this is faulty logic.

If the battery needs to be cooled, then the truck cools the battery. The state of the cabin climate control has no affect on the behavior.

If the truck can only heat/cool the battery when the occupants have the climate controls running then the system is essentially worthless. For example I do not use the heat in the winter.

Agree. But if weed whacker is going and cabin is still warm, then logic from SC that “cabin not cooling is due to system prioritizing battery cooling”should also be invalid (or at least unrelated).

I guess what I’m saying is that the two systems appear to interconnected somehow according to SC. So could jiggering with the controls to mitigate the weed whacker have other adverse effects? Dunno. Here’s to hoping the system isn’t “worthless” I guess. Should be completely independent systems, or at least independently controlled.

 

[Cactus]

Let's hope the engineers can figure this out-FAST. It's strange that R1T owners don't have this AC problem, or do they?
I really want to be excited about my new R1S, but this AC issue "mitigates excitement." LOL.
I've done all I can do on my side (photosync tint on every glass surface, including windshield).
My sons 2017 Jeep Wrangler AC is the absolute best I've ever experienced. It blows cold hard air within about 30 seconds. Hope then engineers can use Jeep's AC as a model.

 

[Chicagofan00]

Just thought I’d add a comment to this thread based on my very limited experience this past weekend. Had the opportunity to do a first mile drive out at the Phoenix service center on Saturday. The appointment was for 2:30pm so the AZ sun had been shining bright all day long and the interior of the R1S was HOT when we got in to start the demo drive. The guide at the service center said that the R1S had been sitting out there all afternoon and hadn’t been recently driven and she unfortunately didn’t get a chance to pre condition the interior either. We cracked the A/C temp as low as it would go and out the fan speed to the max. The air coming out of the vents wasn’t hot by any means but also was definitely not cold. Even the guide commented on and apologized that the air coming out wasn’t very cool and said she was going to have the shop bring it in the back to take a look.

Outside of the A/C the first mile drive was fun and I’d love to be able to bring one home one but if they can’t figure out the A/C then it would be a no go situation here in Arizona.

On a side note, the compressor never sounded overly loud or like a weed whacker. So that was good at least. Lol.

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