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Post-charging fan problem?

Wed Jun 17, 2015 6:56 pm

About two months ago I leased a 2015 Spark EV and I've got it set to delay charge at night on a 220 charger I used for a previous electric car. When I go out to the car in the morning after the car is fully charged overnight, every morning I hear a fan whirring under the hood. It stops as soon as I unplug the car. I understand that the cars make those noises as they're charging - and I understand that fans and pumps will even turn on when the car is done charging from time to time. My concern is that on my Spark EV - that fan is ALWAYS on every single morning when I go out to my car. If I got at 8am, it's on. If I go at 11am, it's on. It's got me thinking that my car turns this fan on and leaves it on even after charging - until I unplug. So the last few days, I've gone to my electric meter to read how many watts this fan is using. I have calculated that this engine fan is pulling 500-600 watts. That seems to be quite a lot of power for a simple fan. And it kind of freaks me out to think that if my car finished charging at 3am - there's a fan that's been running for 8 hours drawing that much power. I called the EV department at Chevy - they were polite but not much help as they said these fans turn on and off. I called my service department and they didn't really know what to do. They aren't sure what the power draw ought to be. Has anybody else found this to happen (or not happen) with their Spark EV? What does yours do? AND if possible, if your fan is on, what kind of power is it drawing? Thanks in advance.

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Location: Portland, OR

Re: Post-charging fan problem?

Wed Jun 17, 2015 11:04 pm

To clarify, do you pre-condition the car with heating/cooling? This would definitely cause the fan to run sometimes, but otherwise the fan shouldn't normally be on.


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Re: Post-charging fan problem?

Wed Jun 17, 2015 11:10 pm

I also charge my 2 cars at night with the Bosch 240V, starting at around 10 PM.

The only time I notice the fan is at the beginning of charging if the cars are cold. It goes away after a while.
Charging is usually done around 2 am, and when I go unplug them around 7 or 8, I don't hear any fan.

When I check power usage online by the hour (SCE) , it does spike up to ~7 kwh at 10, 11, 12 , and gets lower at 1, 2... then goes back the usual .5-.7 kwh that I normally use during the rest of the day.


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Re: Post-charging fan problem?

Thu Jun 18, 2015 9:12 am

I have my car set up on delay charge to be ready at 7am. I usually leave around 8a. Sometimes I use 120v @ 8a, sometimes 240v @ 16a. I've never had the fan running when I've gone out to leave in the morning.
2015 Electric Blue Spark EV 1LT

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Re: Post-charging fan problem?

Thu Jun 18, 2015 3:12 pm

Isn't 600 watts a very high number for a fan to draw? An ICE radiator fan draws about 30 watts.
2015 Spark EV 1LT DCFC
BF Goodrich g-Force Super Sport A/S
ClipperCreek EVSE

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Re: Post-charging fan problem?

Thu Jun 18, 2015 8:00 pm

Thanks for the responses everybody. Very helpful. No Nashco, I don't pre-condition. Yes Nikwax, 600 watts struck me as quite a high number for something as simple and small as a fan. After thinking a bit, it made me wonder if even though my battery gets fully charged, my car thinks it still needs to draw power to keep charging. Last night, I set the Onstar RemoteLink app to send me a text notification as soon as my car was fully charged. I expected that since I had very little charging to get to full, I'd get a text message about midnight or 1am (started charging at 11pm). I woke up about 6am and noticed that I had not received any notification overnight. I checked the app and it said that my car was fully charged. About 3 hours later, I went out to my car to head to work and I found the fan sound on as usual. I checked the wattage like before - as usual about 600 watts being drawn. I unplugged the car got in and drove away - and about 5 minutes later I got a text saying my car was now fully charged. This delayed notification is making me think that either these notifications come really late (like 8 hours) - -or my car thinks it's still charging and that's why it's drawing 600 watts into a full battery. Only thing is - I don't know why the app would show the car as fully charged when it thinks it's not. How quickly do your notifications come?

I called the EV department at Chevy with this new information - and they weren't able to do much other than tell me to take it to the dealer for service. I'll do that tomorrow. They did run a diagnostic and everything showed that it was ok - but there was one thing they couldn't get a read on - the "onboard charging module" failed to send them info. I'm wondering if that module also controls when a car's battery is full and should stop charging.

I'll update here what the dealer finds in case anyone has the same problem. If anyone's got any further insights based on this new post I'm making, I'm all ears.

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Location: Portland, Oregon, USA

Re: Post-charging fan problem?

Thu Jun 18, 2015 8:03 pm

600 watts isn't that high to run the ac compressor on a low setting plus a small fan to pass air over the coils to keep the battery cool. I have seen recommendation to plug the car in if Temps are over 90 degrees to keep battery cool and extend it's life.

And a key piece of info is missing here. Where are you located and what is temperature during day and what is evening temp? If it is hot then it is your ac kicking on. (?) Charging will warm battery and it may take some time to bring temp down to a steady state.

Just curious - Do you connect power to your vehicle right when you arrive home?

2015 Spark EV 2LT w/ fast charge (returned after lease end)

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Re: Post-charging fan problem?

Thu Jun 18, 2015 8:16 pm

Thanks oregonsparky. I'm not sure if it's the ac compressor. It HAS been hot here - I'm in the Bay Area- and we've had a lot of 97 degree days lately. But at night it's really been cooling off. It'll get down into the 50's tonight and I can't imagine my garage (where I'm charging) will be hotter than 75 degrees.

Yes - I am connecting power to the vehicle right when I get home. Just connected it an hour ago at 8:15pm - but it's on delayed charging and won't begin til 11pm. When I plugged it in, it didn't kick that fan on under the hood. And I just checked it again now, and still no fan. It only seems to happen after charging has begun.

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Location: Decatur, Georgia, USA

Re: Post-charging fan problem?

Fri Jun 19, 2015 11:52 am

oregonsparky wrote: I have seen recommendation to plug the car in if Temps are over 90 degrees to keep battery cool and extend it's life.
Well, now, here's a new perspective. Hadn't thought about this until Jeff wrote the above statement. My EVs charge at home after 11PM to take advantage of Georgia Power's TOU rates. So, my Blink EVSE is programmed to do so. The car is more a dumb terminal, therefore.

But if Jeff is correct (and I surmise that he may very well be), then the car and the EVSE *should* have a two-way comm link so that the car can ask for power when ambient temps exceed recommended threshold. In my case, this won't happen because the Blink won't allow it.

Zat make any sense to anyone?

-Bob K.

*Edit: From page 9-33 of the 2014 Spark EV Owner's Manual:
"Do not allow the vehicle to remain in
temperature extremes for long
periods without being driven or
plugged in. It is recommended that
the vehicle be plugged in when
temperatures are below 0°C (32°F)
and above 32°C (90°F) to maximize
high voltage battery life."
2014 Spark EV

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Re: Post-charging fan problem?

Fri Jun 19, 2015 3:46 pm

Both battery pack and 3.3 kw charger are liquid cooled....

I see "loads" from battery conditioning to be the following...

1. AC compressor/heat pump.
2. Fan to blow over ac coils or radiator for liquid...
3. Pump to circulate coolant to battery pack, etc.

I used to write code for embedded systems - actually weapons flying towards a target, but I digress...

If I were coding up the algorithm for when to condition the battery (e.g. turn on that fan that annoys you so...) - I would look at ambient temps encountered over the last couple of days - and if it was high - I would 'condition battery' to bring temps to lower end of range more aggressively. This would increase your range in hot conditions that you might encounter that day.

Also a battery is a very heavy thing - it takes alot to cool it off. A cooling unit doesn't cool it off immediately. To cool it efficiently - It removes heat at a slow steady rate - so you you need to cool constantly to get it "in the zone". (see why the fan is running for a while now?)

Same applies to your home air conditioner. If it is 110 degrees outside and you let internal house temps rise to the same - and you turn on your AC when you arrive home - it has to cool down tons of drywall before you will feel comfortable - it doesn't just cool off the air and you are happy... It has to "remove heat" and it kind of does it "through a straw" to do so efficiently.

On a related topic - I was surprised to see the amount of energy required for "battery conditioning" while driving on a hot day in a recent post....

If I were a good friend of yours and I had a beer or two in me - I would tell you to quit obsessing on the little stuff and move on with your life... And yes, I suffer from obsessive compulsive disorder - so you would probably give me a shout back and say "Hey Pot, this is kettle, and you are looking mighty black!".

That being said - I can see that a bad temp sensor or a sticky relay (if they aren't solid state) might cause excessive running of battery conditioning or fan (respectively).

2015 Spark EV 2LT w/ fast charge (returned after lease end)

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