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Discussion Starter #1
GM installed Automatic climate control to allow for lower energy consumption an maximum range.

The 2013 onwards Gen 1 (at least the ones I've seen) need a revisit of the K33 software as they are:
1) Wasting electricity running the A/C unnecessarily counteractive to heating!
2) Running the A/C momentarily short cycling the Compressor for no reason when certain settings are selected.

Note this happens on low humidity days, Auto defrost = OFF, air selector Auto or Feet only etc.
Battery NOT calling for A/C in ECO or Comfort Modes.

What do we have to do to make GM go back and re-calibrate the K33 software to perform correctly as they envisaged for the initial Volt model year?

If they don't in my case the GM Volt will be the last GM vehicle we ever will purchase as the poor support on this issue and now being out of their warranty is a real bug bear for us.

Cheers,
Martin in the Land down under.
 

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Keep in mind that there are certain reasons the system requires the a/c compressor to engage. Most often as a means of humidity control. I believe that is something that is programmed rather than relying on a sensor for humidity levels.

As for your description of it having the air selector in "auto" does that mean you've hit the auto button (not the auto defrost mode, but regular auto) and went into the climate screen and selected fan only? If you hit auto on the center stack it will engage heat/ac as needed in eco or comfort. What I find is that if I have climate control completely off, open the climate screen and select fan only to activate everything, I generally don't get anything except fan with no heat or ac either indicated on the climate screen or through feeling the air being pumped out of the system.
 

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Exactly. If auto defog is off, fan only will be exactly that, no heat, no cool. A/C uses very little power and it's effect on range is negligible, even in hot weather. Set the temp, hit auto, and drive. There is a gas engine, no range worries.
 

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During the first 2 years of volt ownership, I hypermiled, minimized use of the HVAC, and did all sorts of crazy things in the name of a EV range. Then on October 2015, I slapped on a new set of 18" wheels and lower profile tires, started driving more like Jeff Gordon, and still am able to get 70 mpg lifetime on the dash with my 65 mile per day commute with no charging at work. I'd say just get over it, drive the car, use the AC and heating as needed, and don't worry about maximizing your range.

Remember when ICE vehicles didn;t have much telemetry other than instant MPG and average MPG? We survived. If you ignore the energy usage screen of the volt, it becomes a pleasure to drive and enjoy. GM won't update your software, get used to it. Sure you can ban future GM vehicle purchases for life, that's your right, but it seems silly to focus on one not so great aspect of the HVAC system when all cars have this. All ICE vehicles are less efficient with the AC on.
 

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Discussion Starter #5 (Edited)
Exactly. If auto defog is off, fan only will be exactly that, no heat, no cool. A/C uses very little power and it's effect on range is negligible, even in hot weather. Set the temp, hit auto, and drive. There is a gas engine, no range worries.
Thanks for the replies, however both of you are missing the point - We want heat - but with no unnecessary A/C.
The local conditions are low humidity / dry air which does NOT call for A/C.

You are correct in Fan only mode it behaves. Now GM need to re tweak so that heating in ECO / COMFORT modes say with feet outlet or face outlet (NOT WINDSCREEN) with Auto Defrost =OFF will not run the A/C. Especially in outdoor dry air conditions.

How hard can this be ? Other manufactures have conquered this and in the Volt it is important so you get more heat comfort with less energy used. We were sick of driving the car the first few years in fan only or eco mode until till the heater software was fixed, but it is still not perfect.
Hence our request as the utter stupidity to cool unnecessarily when HEATING is foolish.

Please don't write excuses for GM engineering the software is executed poorly and requires tunning.
 

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Discussion Starter #6
During the first 2 years of volt ownership, I hypermiled, minimized use of the HVAC, and did all sorts of crazy things in the name of a EV range. Then on October 2015, I slapped on a new set of 18" wheels and lower profile tires, started driving more like Jeff Gordon, and still am able to get 70 mpg lifetime on the dash with my 65 mile per day commute with no charging at work. I'd say just get over it, drive the car, use the AC and heating as needed, and don't worry about maximizing your range.

Remember when ICE vehicles didn;t have much telemetry other than instant MPG and average MPG? We survived. If you ignore the energy usage screen of the volt, it becomes a pleasure to drive and enjoy. GM won't update your software, get used to it. Sure you can ban future GM vehicle purchases for life, that's your right, but it seems silly to focus on one not so great aspect of the HVAC system when all cars have this. All ICE vehicles are less efficient with the AC on.
In other words be happy with sub standard GM software turning -
I wonder if the car was made in China (Hint the Volt Gen 1 runs a Chinese made HVAC module) or a Japanese car like a Toyota / Nissan would you be as sympathetic with such low standards ?
In Australia we have experienced better from other brands and cannot understand GM's attitude to this.
Guess GM is still the old GM and they have not learn't from Tesla and others to get the product right no matter when.
 

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All cars have their own karma. GM is not going to fix something that is working as designed.

They did a recall on certain 2013s with poor heating in EV mode. What else do you want?

Buy one of the 'superior' cars that you like better. Although that's a tough thing to do against Volt/ELR.

Sounds like the Down-under version of Blast.
 

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Aus1, I agree with what you are saying.

If you are not defrosting why run the A/C when calling for Heat?
 

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Thanks for the replies, however both of you are missing the point - We want heat - but with no unnecessary A/C.
The local conditions are low humidity / dry air which does NOT call for A/C.

You are correct in Fan only mode it behaves. Now GM need to re tweak so that heating in ECO / COMFORT modes say with feet outlet or face outlet (NOT WINDSCREEN) with Auto Defrost =OFF will not run the A/C. Especially in outdoor dry air conditions.

How hard can this be ? Other manufactures have conquered this and in the Volt it is important so you get more heat comfort with less energy used. We were sick of driving the car the first few years in fan only or eco mode until till the heater software was fixed, but it is still not perfect.
Hence our request as the utter stupidity to cool unnecessarily when HEATING is foolish.

Please don't write excuses for GM engineering the software is executed poorly and requires tunning.
Define "no unnecessary AC" ... It sounds like you are assuming it is not needed, but the engineers clearly disagree. There is a humidity sensor on the windshield of the Gen 1's to help determine this.

And even if it were not needed, a very quick cycle of A/C on then off on an electric compressor occasionally is not affecting your range. It is a drop in the bucket compared to any heating you may require. A quick A/C cycle for checking and/or removing some humidity is NOT cooling the air.

What has got you bothered here is the equivalent of wanting to replace a 40-watt lightbulb with a 39.5-watt lightbulb, because your house uses too much electricity... All the while, your house air conditioner is running full blast at 3300 watts. Oh, and claiming that the additional 0.5 watts in the light bulb is generating too much heat counteracting your air conditioner. ;)

In short, don't necessarily assume that A/C briefly cycling is foolish and not needed. That is your assumption, but it is only that. I suspect the engineers have good reason for doing it, and it is not affecting your range.
 

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I have observed the same behaviour by my 2015 as reported by the OP. I do not recall experiencing this particular behaviour with my 2012.

The issue is not that running the AC when calling for heat (but not defog or auto dehumidify) consumes a lot of energy, it is that additional heat to overcome the unwanted AC does consume significant energy.

At one time, I believed that the battery TMS was engaging the AC but I have observed that this happens even when the battery has had a cold soak and at the beginning of a trip before the battery has had a chance to overheat.

There appears to be no design logic underlying the AC running at such times.

KNS
 

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I agree that the AC runs excessively when it should be heat only. I find it annoying and I feel like it is wasting energy. Just how much energy is hard to tell. It could be a lot or a little.

I am quite confident in predicting that GM will not go back and re-engineer a feature on a car that is out of warranty and they don't even make any more. Tesla probably would, but they are out of my price range. Probably none of the other major manufacturers would make any sort of improvement on a sold vehicle unless it is a safety recall issue.

Despite this and several other even worse flaws with my Volt, I am still overall very happy with it.
 

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As the Gen 1 Volt's hit end of warranty, I think we're going to see some serious hacking taking place.
Ubuntu for Volt?!?
 

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As others have already said, a/c with the heater and/or defroster serves to control humidity in the cabin. It also keeps the a/c system (oils/conditioners/lubricants and refrigerant) circulating momentarily through the lines in the off season to prevent issues and prolong the life of the system.

My wife had an older Honda CR-V and every year and a half the compressor would internally grenade and we would have to replace the complete system (between $3000 and $5000)... After 4 times we dumped it, it was a very common issue for that generation CR-V. I'm not sure if this was the problem, but if it cycled the a/c and it prevented those replacements I wouldn't have been upset.

There is a reason it operates the way it does; there are bigger and better fights to have with GM than this. Every modern vehicle I've owned does the exact same thing so if you want to write off GM for doing this, your list is going to expand greatly.
 

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GM installed Automatic climate control to allow for lower energy consumption an maximum range.

The 2013 onwards Gen 1 (at least the ones I've seen) need a revisit of the K33 software as they are:
1) Wasting electricity running the A/C unnecessarily counteractive to heating!
2) Running the A/C momentarily short cycling the Compressor for no reason when certain settings are selected.

Note this happens on low humidity days, Auto defrost = OFF, air selector Auto or Feet only etc.
Battery NOT calling for A/C in ECO or Comfort Modes.
The high voltage pack needs cooling too. When the compressor is running to chill the battery coolant, it'll show on the indicator even though it's not blowing cabin air past the evaporator.
 

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I have noticed my AC compressor cycling ON/OFF when using the HEATER/DEFROST mode in our 2017 GMC Acadia.
 

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Even in a low humidity climate wouldn't breathing and sweating humans eventually raise the humidity in an enclosed space?

The a/c compressor probably also cycles occasionally in hot weather for battery thermal management.
 

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In other words be happy with sub standard GM software turning -
I wonder if the car was made in China (Hint the Volt Gen 1 runs a Chinese made HVAC module) or a Japanese car like a Toyota / Nissan would you be as sympathetic with such low standards ?
In Australia we have experienced better from other brands and cannot understand GM's attitude to this.
Guess GM is still the old GM and they have not learn't from Tesla and others to get the product right no matter when.
Aside from the fact that the AC is needed for cooling the battery (pointed out by another forum user), your request to modify the HVAc system is similar to volt owners asking GM to open up the SOC of the battery to use more of the 16-17kwh battery. Yes, it's technically feasible since the ELR digs deeper into the battery, but I don't expect GM to just give us a software update to give us more range. It's just not going to happen.
 

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I have been mildly annoyed when I see my Volt do what OP is talking about... just asking for heat (not even on windshield) and I see a/c cycle on/off. I agree it seems unnecessary, but there could be something we're missing... most cars automatically turn on the a/c when you select windshield defrost... even in the winter when you only want heat and the air is dry. It may or may not be obvious on the controls that this is happening, but you can usually hear/feel it kick on even if there is no indicator light. It's doing this to control humidity and clear the windshield faster... yes, the air outside is dry, but your breath isn't.

Sure, we weren't asking for anything windshield-related, so fogging up doesn't seem like a concern, so why is it running? I don't know, perhaps it is poor programming or perhaps it's something specific to Voltec that we just aren't aware of. I'd say there's about a 0% chance of GM updating the programming, and the energy hit is small, so I don't worry about it. Excessive cycles on the compressor could be a legitimate concern if it causes it to fail early, but sometimes more frequent use of a system leads to better reliability than occasional use, so it's not clear this is a bad thing.
 

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1st world problem here........have a nice day.
 

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my biggest issue with this isn't that it wastes a little energy or that I lose a little range, it's that I have to mess with the climate controls so often. On a sunny but cool fall or spring day, the cabin will be warmer than my temp setting. I climb into a comfortably warm, naturally pre-heated cabin and the GD car turns the AC on and starts blowing cold air in my face! On a cold day! On my BMW with an actual on/off switch for AC, once I set the temp controls in the fall, I never have to touch them again. If I get in a warm car in the fall, the heater just blows lower--no AC turning on automatically.

P.S. I know GM isn't going to do anything about this, and I know I'll have to live with this until my car is out of warranty. After that, I could put a switch in myself.
 
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