[scottf200]

Nice describe with some details from a GM Techlink article: http://www.sandyblogs.com/techlink/Jan 2011 Techlink F.pdf

Volt Engine Operation in Cold Ambient Temperatures

Volt owners may notice that during a cabin conditioning (remote start) event in cold ambient temperatures, the internal combustion engine (ICE) runs even with the vehicle plugged into a charger. Owners may also note that while driving in cold ambient temperature the ICE will run for extended periods or cycle on and off. A message will display on the instrument cluster that states ENGINE RUNNING DUE TO TEMPERATURE. This may occur even when the battery is fully charged. No DTCs will be associated with this condition.

At ambient temperatures of approximately 25° F (–4° C) or below, the ICE will operate to assist in warming the coolant used to warm the vehicle’s cabin. After the coolant temperature reaches approximately 150° F (65° C), the ICE will turn off and remain off (as long as the battery state of charge is sufficient) until the engine coolant temperature drops to approximately 104° F (40° C), at which time the ICE will restart. This function will continue as long as the ambient temperature is approximately 25° F (–4° C) or less while driving. After the ambient temperature rises above approximately 25° F (–4° C), the vehicle will resume normal electric operation (as long as the battery state of charge is sufficient).

This is normal operation and no repairs should be made to correct this condition.

[UPDATE]
You typically can limit your Engine Running Due to Low Temp ERDTLT by using COMFORT and low fan settings (1,2,3).
See: COMFORT-setting-limiting-quot-Engine-Running-due-to-low-temperature-quot-ERDTLT
http://gm-volt.com/forum/showthread...ne-Running-due-to-low-temperature-quot-ERDTLT
[/UPDATE]

[UPDATE]
Late 2012s have a Very Cold config option that changes the temp from 25F to 14F. Hardware change.
Update: Response from ari_c's Volt Advisor

The difference for this feature is actually in the hardware itself, because the heating system is designed differently. Unfortunately there is not an upgrade for the engine assisted heating options, but if this changes in the future we'd be happy to let you know.

[/UPDATE]

 

[therfman]

I wonder if the electric heater works during this cycle. Once the ICE has bought the coolant temp up to 65C, does the electric heater turn on to at least try to keep the coolant warm despite the cold ambient temps? If the only thing providing heat is the on/off cycle of the ICE, I'm afraid the Volt won't be much of an EV for me in winter; during the months of January and February, it's unusual for the temperature to ever climb above -4C, day or night.

 

[maestro77]

I'm wondering the same thing.....
SURELY the high voltage battery will do it's very best to keep the cabin-heating-coolant adequately warm during the time period the ICE has cycled off.
However, can anyone with specific knowledge (rather than just guesses) comment??

 

[Slapshot28]

I'm not sure if this will help, but it is written by our definitive Volt expert (***) and has quite a bit of detail:

http://gm-volt.com/2010/12/09/the-chevrolet-volt-coolingheating-systems-explained/

Check out the comments below the article as well, because *** provides an adiitional schematic at Comment #36.

 

[maestro77]

Thanks Slapshot28,
The third block diagram does seem to indicate a 360V Electric Heater is in series with the direction of flow of coolant from the ICE to the Cabin Heater Core. And that even more specifically there is a bypass coolant loop recirculating coolant from the Electric Heater specifically to the Cabin Heater Core "During EV Operation".

 

[BlackVolt]

I understand the ICE will start at 25° F (–4° C) but what about in very hot temperatures? The owners manual advises the ICE may start due to temperature of either hot or cold ambient temperature. Does anyone know the answer at what hot temperature will the ICE start?

 

[solar_dave]

We have driven ours in 115F temps and the ICE has not come on. But it is generally plugged in when not in use and does make a power draw every few hours, I assume to condition the battery, and when driven the AC is at least on in ECO mode.

 

[BlackVolt]

We have driven ours in 115F temps and the ICE has not come on. But it is generally plugged in when not in use and does make a power draw every few hours, I assume to condition the battery, and when driven the AC is at least on in ECO mode.

That's interesting. I wonder what would happen if the Volt was not plugged in and was sitting in a hot parking lot at this temperature. I wonder if the ICE would start to help with the cooling of the battery etc. There must be a threshold for the ICE to start in hot temperatures. I wonder if Rusty or any of those guys have an input to this.

 

[bluelight_tj]

It was my understanding that the volt will circulate collant to help to maintain a certain range of temp for the battery. I know if plugged in to power it draws from there. If not i would think it would draw from the battery. Not sure what would happen if the battery was depleted though. From what i have heard owners have comment to hearing humms and noises from the car which are normal as the pumps kick on and off at night.

 

[Roadburner440]

The car certaintly makes some odd noises.. Especially when plugged in. The night we brought ours home, and hooked it up to the charger I unplugged it as it almost sounded like a bug zapper going off.. I have now just come to accept it as normal as everything is always fine when I go out in the morning. Can also occassionally here a pump come on and go off. As far as in the heat we have had some pretty hot days here in Florida, and to my knowledge the engine has not kicked on because it was to hot... Curious to see how the cold weather operations are since we will be moving to Virginia in 2 months..

 

[therfman]

We're bound to see morning temps below -4C here within a few weeks... we'll see then!

 

[Ohm]

I just ordered mine yesterday. I'm a previous Prius owner, and I'm very interested in knowing how this works. The major downfall I saw in the Prius was the amount of preheat time it would spend warming things up each day. I only have to drive 5-10 miles a day, and live in the middle of PA - where temps range between 0 and 30 throughout the winter. Just as I get to where I'm going, the Prius would decide it was warm enough to turn off the ICE. I was really hoping the Volt would solve that problem - but this thread makes me wonder. Furthermore, I was hopeful that I would be able to have the Volt preheat the cabin each day (while plugged in) so I wouldn't be making my short trip in a freezing car.

Am I out of luck here? Do I need to cancel my order and just go with a Leaf instead?

 

[tboult]

Do you have a garage? If so the car will likely be 30-45F and so the engine will not start in the garage. You can definitely preheat and get a warm cabin, which should last you 10m with no problem. The return trip will be different unless you plug n at work.

If the outside temp is <25F the volt will start due to the temp. Mine has done it 4 times now.
I've been doing 75 went it goes on and off. The batter still allows a full driving experience even when its that cold, the ICE just turns on to keep the battery a bit warmer.

Each of my temperature-based start lasted about 30sec to 1min. So in a 10m trip at 0, you would like have the ICE on for a part, but not nearly all of it.


My recommendation is to visit your dealer and see if you can take a demo home over night on a cold day.

 

[Ohm]

I do have an insulated and attached garage, but don't have heat going to it, nor do I have an insulated garage door at this point. If I run it through a preheat cycle, do I need to worry about keeping the garage door open because of the ICE? I've thought about possibly improving things by getting insulated garage doors or possibly getting heat out to the garage, but have no idea if it would be worth while - and if the ICE does turn on during preheat, I don't want to be making things worse.

I'd be surprised if the dealer let me take one home - they only had one (that he claimed they couldn't sell at this time), and I've never seen another on the road around here. Besides that, it's in the mid-40's this week - nowhere near cold enough for the typical winter day I'm expecting.

 

[scottf200]

I do have an insulated and attached garage, but don't have heat going to it, nor do I have an insulated garage door at this point. If I run it through a preheat cycle, do I need to worry about keeping the garage door open because of the ICE? I've thought about possibly improving things by getting insulated garage doors or possibly getting heat out to the garage, but have no idea if it would be worth while - and if the ICE does turn on during preheat, I don't want to be making things worse.

I'd be surprised if the dealer let me take one home - they only had one (that he claimed they couldn't sell at this time), and I've never seen another on the road around here. Besides that, it's in the mid-40's this week - nowhere near cold enough for the typical winter day I'm expecting.

I've been preconditioning (heating) in my closed garage for a while. I leave the garage door closed. I'm not sure I've heard a definite realworld real owner example/scenario when the ICE/GG would come on during preconditioning. It comes on when you start the car for sure when it is below 25F.

This all has been talked about a lot. The modern Volt ICE setup with the catalytic converter *RIGHT* next to the exhaust manifold reduces emissions extremely fast by comparisons to other vehicles. As has been stated you could not hurt yourself even if you wanted to running the modern ICE in a closed garage. Remember it on runs 10 minutes up to 2 precondition requested times.

I'd probably insulate my garage door ($) but certainly not heat the garage ($$$). Youtube videos of varous insulation kits/etc: http://www.youtube.com/results?search_query=Garage+Door+Insulation+Kit

 

[tboult]

My garage is attached, only a 2 walls are insulated, doors are not insulated. When its <-10F (i.e. very cold) and windy the garage gets below 25 and I will not precondition as I don't want the ICE running in the garage with the door shut. Furthermore when its that cold I'm sure the car's ICE will turn on and provide heat almost right away.

When its at 0F, garage hovers around 32F so I may still choose to precondition. Will have to wait and see.

You can be sure the ICE will never turn on in a LEAF Less certain you'll be albe always make it to your destination though with a 20m R/T commute you would be fine

You might compare
http://blogs.cars.com/kickingtires/2011/04/a-winter-in-the-nissan-leaf.html
http://blogs.cars.com/kickingtires/2011/04/a-winter-in-the-chevy-volt.html

some some of the their others comparison posts.

 

[Ohm]

Thanks for the replies and links - I'm feeling much better about my order now. I pulled up my daily trip on Google maps - looks like it's only 5.3 miles round trip, and I work from home - this trip is just to take the kids to school, so there's little downtime between the there and back. I'll go with the garage insulation and see how things go.

 

[Rusty]

I pulled up my daily trip on Google maps - looks like it's only 5.3 miles round trip

Then you should be able to pre-heat on the return trip without worrying about range too. You can pre-heat without the car being plugged in. It just draws down the battery. But it may be worth it to get into a warm(er) car...

 

[Ohm]

I did one better - I created a PC app to simulate the OnStar commands for starting the engine, then set that up as a scheduled task to run 20 minutes before I leave each weekday (since I leave at the same time every day anyway). I'm thinking I'll enhance it a bit once I get the hang of how far in advance to make it run, if I need one cycle or two, and perhaps factor in those things based on weather. I'd also love to make it so it doesn't start automatically if I'm not at home (I.E. vacation), but haven't quite figured that one out yet. Maybe I can tie it in with my Android phone's GPS location... I'm open to suggestions.

 

[tboult]

Did you get a real API from them, or did you just reverse engineer it? Care to share?

Maybe make it an android app then ti can easily access your location and ask if you are away (or just do the right thing).
Getting the PC to connect to the phone is tricker (I guess your phone could push the location).