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Discussion Starter #1 (Edited)
I think I've finally got a handle on just how the Gen 1 Climate controls work in my Volt.

On Battery
Fan-Only: Just what is says, unless the battery needs to be cooled or heated to maintain integrity in which case you may get some cool or warm air depending on your temperature setting. Full range of fan speeds are available.

ECO: Reduced fan speed range, reduced resistance heating capability (3 kW), reduced A/C (3? kW)

Comfort: Full fan speed range, full resistance heating capability (7 kW), full A/C (5 kW)

Windshield Defrost: Full fan speed range, full resistance heating capability (7kW), full A/C (5 kW)

On REX/ICE
Fan-Only: Full range of fan speeds are available and you get full (engine) heat or A/C...maybe, needs further testing per the temperature setting. Basically it acts just like Comfort mode.

ECO: Reduced fan speeds, full (engine) heat or A/C per the temperature setting.

Comfort: Full fan speed range, full (engine) heat or A/C per the temperature setting.

Windshield Defrost: Full fan speed range, full (engine) heat or A/C per the temperature setting.


So in short it appears that "Eco" and "Comfort" modes really only matter when operating on battery power.
 

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I don't think you get A/C in fan only mode even while running the engine. I can't easily test now to confirm, but it would surprise me if that ran the A/C. Of course, A/C might run at times for battery cooling, and that might happen while running the engine. The battery cooling seems to run a lot when the weather is over 90 F.
 

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I don't think you get A/C in fan only mode even while running the engine. I can't easily test now to confirm, but it would surprise me if that ran the A/C. Of course, A/C might run at times for battery cooling, and that might happen while running the engine. The battery cooling seems to run a lot when the weather is over 90 F.
I know that in my old 2011 I didn't get A/C in fan only mode running the ICE, and that you don't get A/C in fan only mode in the 2016. Why would the car waste power on the A/C system if you are requesting fan only?

Now, if you direct air to the windshield it may kick on the A/C to de-humidify the air... but not even sure on that.

When running my 2016 on long trips on the ICE with fan only, you can feel the air get cold about once an hour when battery thermal control system kicks on the A/C compressor for battery cooling. This is in temperatures low enough to run in fan only, battery thermal management probably requires more A/C compressor useage in hotter weather, but you don't notice it because you are already using the A/C for cabin temperature control.

Keith
 

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Discussion Starter #4
I don't think you get A/C in fan only mode even while running the engine. I can't easily test now to confirm, but it would surprise me if that ran the A/C. Of course, A/C might run at times for battery cooling, and that might happen while running the engine. The battery cooling seems to run a lot when the weather is over 90 F.
Okay, if it warms up again I'll re-test that to check. Meanwhile I changed my OP.
 

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...Now, if you direct air to the windshield it may kick on the A/C to de-humidify the air... but not even sure on that...
Yes, that seems right to me. When I use the windshield defog/defrost button, it seems to run the A/C, and it runs it a lot, sometimes at the same time as heat, (to dehumidify).
 

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Okay, if it warms up again I'll re-test that to check. Meanwhile I changed my OP.
I think the only difference while running the engine is that resistance heat is off and you get full engine heat in any mode (even fan only mode), assuming your temperature set point is high enough to call for it.

That seems consistent with how a typical ICE car works. "Fan Only" is equivalent to "A/C off" in an ICE car. And in that mode, if you dial up the temperature setting, you get engine heat in an ICE car.

So in the Volt, "Fan Only" means A/C and resistance heat off (unless needed for the battery). And "Eco" means reduced power for A/C, resistance heat and fan speed.
 

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I know that in my old 2011 I didn't get A/C in fan only mode running the ICE, and that you don't get A/C in fan only mode in the 2016. Why would the car waste power on the A/C system if you are requesting fan only?
I've gotten AC in Fan Only, presumably when the AC compressor kicked on to cool the battery.

I've had heat kick way up in ECO, when the engine started and it could use engine waste heat instead of burning electrons to run the resistive heater.
 

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Maybe we'll get a couple fewer people kvetching about how lackluster the climate control is in one breath and complaining about ERDTT with the next. ;)
 

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I use Auto, works ok most of the time except in some winter conditions where you have to hit the windshield defrost button from time to time to clear the windshield inside or out. When my feet get cold, it usually means I left it in windshield defrost mode.

I am comfortable but get lousy range in colder weather. Already seeing 27-30 miles vs. 37-40 miles.
 

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So in short it appears that "Eco" and "Comfort" modes really only matter when operating on battery power.
Mostly, but not exactly.

When in "gas"/CS mode, at start up when the engine is still cold and takes awhile to warm up, the Volt will use electric power to warm up the air coming out of the vents quicker in Eco/Comfort than in "Fan Only".

There are also some scenarios where the engine would not be running enough to maintain adequate temperatures and Eco/Comfort mode would use battery power to make up the difference, but in "Fan only" it would not. For example, in slow stop-and-go traffic in a traffic jam. Or if you stopped the vehicle for several minutes waiting to pick someone up (or any other reason).
 

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I've gotten AC in Fan Only, presumably when the AC compressor kicked on to cool the battery.

I've had heat kick way up in ECO, when the engine started and it could use engine waste heat instead of burning electrons to run the resistive heater.
I too have had the AC compressor show up on the climate screen with fan only when it is really hot outside. I can also force it to happen by punching the accelerator a lot (no officer, I'm not racing Mustangs, Camaros, or Challengers)
 

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I've noticed in my '13 that the a/c locks out below 30° F and will not provide dehumidifying, unless I press the defrost button, then it will run. Above 30°, it will run in conjunction with the heat and keep the windows clear. If you use "auto defrost", the electric heat and a/c will run even in "fan only." I leave that off.
 

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I think I've finally got a handle on just how the Gen 1 Climate controls work in my Volt.

On Battery
Fan-Only: Just what is says, unless the battery needs to be cooled or heated to maintain integrity in which case you may get some cool or warm air depending on your temperature setting. Full range of fan speeds are available.

ECO: Reduced fan speed range, reduced resistance heating capability (3 kW), reduced A/C (3? kW)

Comfort: Full fan speed range, full resistance heating capability (7 kW), full A/C (5 kW)

Windshield Defrost: Full fan speed range, full resistance heating capability (7kW), full A/C (5 kW)
5kW for automobile A/C seems very excessive. A typical 2ton residential HVAC unit only consumes about 3.5kW (11-14A @ 240V). Hard to believe a small car cockpit could consume more power than 2Ton residential unit.

A typical window shaker A/C unit consumes about 600-1200W (depending on size). This would seem more than enough cooling for a auto's interior.
 

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Is there any documentation as to how much power each mode takes? I know there is percentage at the bottom, by I'm looking more for battery hit over the ride ( like -5 miles of left on for remainder of ride).
 

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Discussion Starter #15
5kW for automobile A/C seems very excessive. A typical 2ton residential HVAC unit only consumes about 3.5kW (11-14A @ 240V). Hard to believe a small car cockpit could consume more power than 2Ton residential unit.

A typical window shaker A/C unit consumes about 600-1200W (depending on size). This would seem more than enough cooling for a auto's interior.
Sorry, typo. That should have been 1.5kW NOT 5kW.
 

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Is there any documentation as to how much power each mode takes? I know there is percentage at the bottom, by I'm looking more for battery hit over the ride ( like -5 miles of left on for remainder of ride).
There are too many variables, including outside temp that makes every situation different.

with no heat or AC you can get about 50mi from a gen1 at optimum temps.
At the coldest I've seen (-25C/-13F) with heat blasting max, about 25. I believe max AC folks see about 40 optimum in the heat of summer.
Something in between will be between those points on the continuum.

5kW for automobile A/C seems very excessive. A typical 2ton residential HVAC unit only consumes about 3.5kW (11-14A @ 240V). Hard to believe a small car cockpit could consume more power than 2Ton residential unit.

A typical window shaker A/C unit consumes about 600-1200W (depending on size). This would seem more than enough cooling for a auto's interior.
The actual 5kW value (being incorrect) aside, the AC in a vehicle has to be much higher powered than a fixed residential unit.
Residential units are designed and spec'd to maintain a temp or change it slowly over hours. This automotive unit has to cool the vehicle in minutes. That means significantly higher power.

The same goes for the heater. 7kW is a fair sized electric furnace capable of heating a small home. A small 750W space heater would probably be able to heat the tiny cubic ft of the vehicle cabin. But users demand heat NOW, not in 2 hours.

So they spec a much more powerful unit to get things to temp ASAP, then dial back the power to a low maintenance level. AC cycles on an off at a lower rate (500W or so) and heat drops to 500W-1000W)
 
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