Cold Weather Observations

[Russael]

I experienced that yesterday as well.  Temps were -4 here, and even though I preconditioned, the car kicked over to that 'engine enabled for system performance' mode and gave me a yellow EV icon after about 1 1/2 miles of travel.  All three modes were still available, but the car overrode it and started the ICE as it needed.

 

It's currently -1 outside, so I'm guessing it's going to do that again this morning.

[Russael]

Just arrived at work and the temps reached as low as -6F... and I got here entirely in EV mode, and I was running climate at 70.  :headscratch:

[frbill]

Russael

Posted Today, 07:11 AM

Just arrived at work and the temps reached as low as -6F... and I got here entirely in EV mode, and I was running climate at 70.

 

If your battery is warmed up the ice should stay off, do you precondition? Are you parked outside overnight?

Edited January 8, 2014 at 01:17 PM by frbill

[larryh]

I precondition the car in an attached garage that is about 20 F warmer than outside.  I have only been able to make it to work entirely in EV mode once when the temperature was below zero (-5 F).  For all my other trips (several of them), the ICE has come on (with climate on).  I don't know what criteria is used to turn on the ICE.  I have always been able to get to work entirely in EV mode when the temperature is above zero.

Edited January 8, 2014 at 02:08 PM by larryh

[Russael]

My car is in a detached garage that isn't climate controlled or insulated, and yes, I do precondition.  Thing is, even if you do precondition, the trunk isn't warmed (I've never heard the fans drawing cabin air in to the trunk to warm the batteries).  I preconditioned last night and within 2 miles, the ICE kicked on and it was -1, and with the same scenario today, with temps -6, I made it in all EV mode.  I won't be able to make it back in all EV though.  I'll may drive home in EV Later mode to make sure the engine warms sufficiently and prevent Oil Maintenance Mode.

[SteveEnergi]

My trunk warms when I precondition. I've been in my trunk before leaving for work and it's nice and warm.

[Russael]

Drove home today... outside temp was 15 and the car was sitting in the sun.  I opened the door to put my stuff in, noticed it felt decently warm, so I figured I'd drive home without climate and just stay on battery power (said I had 6 miles of range which is just enough).  About a mile from the office, the ICE kicked on.  This is weird, because I have driven the car before when it was 9 outside in the dark without climate and didn't have the engine kick on.  Car sat about 4 hours for the night trip and about 6 hours this afternoon.

 

I have no idea what criteria the system uses to determine if the ICE should be on or not due to the seemingly randomness of it.

 

But, since it did, I turned the climate back on and went home in warmth. :)  The engine didn't turn off until I pulled in my neighborhood, so it was on about 15 minutes.

 

I'll have to check my trunk next time I precondition to see if it's any warmer back there.  I did pop the trunk this morning to put my grocery bags back in, but I don't remember it being all that warm.  I didn't hear any of the fans for the battery either.

[larryh]

Yes, the criteria for turning on the ICE doesn't seem to be consistent.  This afternoon, at around 2 F, the ICE started right up.  It stayed on for about 2 miles.  I was then able to make it almost home in EV mode (1 mile remaining on the HVB) before it displayed a notification stating that EV Now mode is not available (the EV mode selection screen appeared with EV Now and EV Later crossed out).  However, the ICE did not start.  I made it to my driveway and then the ICE started.   I can't discern any regular pattern to when the car decides to disable EV Now mode in cold weather. 

 

Others in the C-Max Energi forum claim that the amount of power used by the heating element is affected by fan speed.  The higher the fan speed setting, the more power the heating element draws.  Same is true for A/C.  I will have to try that out tomorrow (but not the A/C). 

Edited January 9, 2014 at 12:59 AM by larryh

[tseibel76]

I think a major factor in when the car decides the ICE needs to come on is how long it has been sitting out in the cold.  I have a heated garage and the ICE has never fired on my way to work in the morning.  I have driven to work in -31 F and the ICE still did not fire.  I probably have driven to work in -20 F or colder on at least 20 mornings so far this winter and the ICE has never fired.  Granted, my drive is under 15 minutes.  My guess is if I had kept driving for a while, the ICE would eventually fire.  

 

EV Now definitely keeps the ICE off more than EV Auto, under similar conditions.  However, I'm not exactly sure of the factors that make EV Now unavailable either.  

 

I always keep my climate in full manual mode, set to LO, to the floor and on the lowest fan speed.  This does a pretty good job of keeping the windows from frosting up.  When I need heat (or when the ICE fires and I figure I might as well run the heat), I just bump it up from LO to 60 F, keep it on the floor and keep it on the lowest fan speed.  This takes the chill off. 

[larryh]

In the morning, after preconditioning in a garage that is above zero, turning on climate with the temperature set to 60 or above is what causes the ICE to turn on when the outdoor temperature is below zero.  At least that is what the EV Info Power screen states:  Engine on due to heater settings.  I assume that if I had the temperature set to LO instead that the ICE would not come on for me either.  The Engine on due to heater settings only seems to happen when the temperature is below zero.  Above zero, it does not happen.

 

After sitting out in the cold, the conditions for turning the ICE on are different.  Leaving climate control off does not prevent the ICE from starting.

 

This morning when the temperature was below zero, the power consumed by the heater is maxed out regardless of the temperature or fan settings. 

Edited January 9, 2014 at 01:30 PM by larryh

[SteveEnergi]

This brings up another question.  I set to "precondition" the car to 85 degrees, so I can get the car as warm as possible prior to pulling out of the garage.  Now, if I leave the climate "on" and set to 70 degrees and "auto" will the car then try to cool to 70 degrees thereby wasting the heat/energy?  Of course, if I leave climate "off" when pulling out of the garage nothing will happen until I drive about 2 miles then the windows fog over and then I'm stuck turning climate back "on" to clear the windows.  I'm not about to roll down the windows or even crack them when the temp is near zero.

 

Thoughts?

 

Steve

[larryh]

I'm not sure that is even possible to warm the car up to 70 F when preconditioning in cold weather.  If you set climate to auto, the car will do whatever it takes to get the temperature to what you set it to.  I notice that when I turn down the temperature (with climate in manual mode), cooler air comes out of the vents. 

 

If you set climate to manual and the temperature to LO, the ICE will probably remain off if it is not too cold.  It will clear the windows, but cold air will blow from the vents.

Edited January 9, 2014 at 09:41 PM by larryh

[SteveEnergi]

Thanks, Larry

My car gets pretty warm when  I precondition.  It seems like it's at least 70 degrees when it's time to go.  I park in an insulated garage that helps and the temp in there doesn't get much below 30.  This morning I had the car set to 72 for preconditioning and left climate off, all the way to work.  It was about 22 degrees outside, light snow and the windows didn't fog, so my 5.7 mile commute was all battery.

[larryh]

I checked the motor and coolant this morning as my car was preconditioning and both the motor and coolant reservoir were stone cold, so there goes that.  I guess in that case maybe the electric heater is a closed loop system?

 

I found a block diagram showing the cooling system here in the section entitled HEV/PHEV Cooling System Diagnostics:  https://qa2k3.motorcraftservice.com/vdirs/diagnostics/pdf/OBDSM1303_HEV.pdf

 

This is an excerpt from the document:

 

The cooling system in the Plug-in Hybrid has been designed to include two functional cooling loops. This system is designed to maximize cooling efficiency when the vehicle is running on either the gas engine or the electric motor. The system operates in one of two different modes. 

 

The first mode is the main or "combined" cooling loop mode which provides coolant flow through both the gas engine and the cabin heater core. While in this loop, both the gas engine and an electric heater can be used to maximize the heat transfer to the coolant thus providing both an increase in the engine metal temperature and heat for the vehicle cabin. 

 

The second cooling mode is the "isolated" loop mode where coolant flow through the cabin heater core is isolated from the engine block. This loop is intended to provide cabin heat when the gas engine is not running. Coolant flow is maintained in the "combined" loop by default (isolation valve de-energized), and by energizing the isolation valve coolant flow is maintained in the "isolated" loop.  

 

So preconditioning uses the isolated loop where the coolant is circulated through the electric heater and heater core, isolated from the engine block. 

 

An Engine Block Heater heats the engine block and coolant outside of the isolated heater core loop and thus will not help in heating the cabin during preconditioning.  Preconditioning and the Engine Block Heater operate independently heating different parts of the car:  preconditioning heats the car's interior and the Engine Block Heater heats the engine itself. 

 

There are two electric pumps, one for the main coolant loop and one for the isolated loop for the heater core.  I wonder what happens when we turn climate control off.  I assume that the pump for the isolated heater core loop turns off.  But then is the heater core coolant no longer isolated when climate control is off?  Does it mix with the cold engine block coolant that has not been warmed by preconditioning?  If the isolated loop is no longer isolated, then the heater will have to work harder when climate control is turned back on to heat the colder coolant that has now entered the isolated coolant loop for the heater core. 

Edited January 11, 2014 at 06:08 PM by larryh

[Russael]

Very cool.  Thanks for the posting.  *saves it to my Fusion folder*  At least it answers the question as to how the heating system works.

[larryh]

The temperature sensor for the coolant seems to be in the "Isolated" loop containing the heating element and the heater core.  So this morning, I turned on climate in EV Now mode, with the ICE off, and observed the coolant temperature using ET mode.  I left the car parked.  The temperature this morning was 26 F.  I observed the following readings:

 

Time   Temp C   Climate On/Off

7:09   -4       On

7:10   13       On

7:11   33       On

7:12   45       On

7:13   52       On

7:14   56       On

7:15   58       On

7:16   60       On

7:17   61       On

7:18   60       On

7:19   61       On

-------------------

7:20   66       Off

7:21   66       Off

-------------------

7:22   52       On

7:23   56       On

7:24   57       On

--------------------

7:25   68       Off

7:26   70       Off

7:27   70       Off

7:28   69       Off

7:29   67       Off

7:30   66       Off

-------------------

7:31   48       On

 

The heating element heats the coolant to around 60 C. 

 

If climate is turned off, the sensor temperature increases initially before falling.  The coolant must no longer circulate.  In addition, the sensor must be close to the heating element or the warm coolant rises up to the sensor which is near the top. 

 

When turning climate back on again, the coolant temperature falls rapidly as the coolant starts circulating again.  It is unclear whether this is due to mixing of coolant from outside the "isolated" loop with that inside the "isolated" loop or the coolant inside the "isolated" loop has cooled off with the heating element turned off.  Leaving climate off for two minutes, the temperature fell to 52 C.  With climate off for 5 minutes, it fell to 48 C.  I am inclined to believe that the cold coolant from outside the "isolated" loop mixed in with that from the "isolated" loop.   The temperature drop after 2 minutes was 8 C, and after 5 minutes it was 9 C.  If that is the case, you don't want to turn climate on and off frequently unless all the engine coolant is heated.  I will have to try turning off climate for a shorted period of time to verify. 

Edited January 12, 2014 at 02:03 PM by larryh

[frbill]

Larry, how are you monitoring the coolant temp? Are you using a scan gauge or something like it. I am very impressed by the data you have listed in the post.

 

Thanks

 

Fr. Bill

[larryh]

I do not have a scan gauge.  I wish they made a device that would allow the OBD II data to be downloaded to a computer to analyze it.  Someone should provide an application for MFT that does that. 

 

I am using Engineering Test Mode:

 

http://fordfusionhybridforum.com/topic/6749-engineering-test-mode/

Edited January 12, 2014 at 04:39 PM by larryh

[murphy]

The Davis CarChip Pro will capture 5 parameters at a time, one of which has to be speed.  The software will display a table of the data or a graph of each parameter.  I have not found a way to export the data so it can be imported into Excel for example.  I used to put it into the car on the first day of the month and remove it on the last day of the month and download the data and then clear it out for the next month.  I recorded speed, Engine RPM, Coolant Temperature, Battery Voltage, and Intake Air Temperature.  It can be removed and downloaded at any time and then put back without affecting the month of recording.

 

This is the one that I have.

 

http://www.amazon.com/Davis-Instruments-8226-CarChip-Pro/dp/B000SKQD9O

 

There appears to be a newer model than the one that I have.

 

http://www.amazon.com/Davis-Instruments-8226B-CarChip-Model/dp/B001A0C7F0

 

The one that I have only worked correctly with the next to newest firmware installed and the car set as a Honda/Saturn Hybrid.

This was back when I first got the 2010 Fusion Hybrid.  They were not interested in creating a setup file to work with my car. 

With this setting it also works with my 2013 Fusion Energi.

[larryh]

Thank you for the above information.  It would be nice if it would record things like MPGe and HVB temperature. 

 

Last week, when I used the EBH for four hours, I noticed that the coolant temperature reached 30 C.  During the last hour, I also preconditioned the car with the 120 V charger.  The coolant temperature remained at 30 C during the last hour before the GO time.   So I assume that when preconditioning began, the "isolated" loop was activated and the heating element now began warming the coolant in the "Isolated loop" which was already at 30 C (86 F).  However, for the hour that preconditioning occurred, the coolant temperature did not change.   It appears the 120 V charger was only able to maintain the coolant temperature at 30 C during preconditioning and couldn't warm it any further.  The car probably blows in cold outside air through the heater core during preconditioning.  The coolant isn't warm enough to warm the cold outside air much.  In addition, the cold outside air is probably cooling the heater core significantly.  It appears, the 120 V charger just can't keep up.   The EBH does a better job of warming the engine coolant than preconditioning with the 120 V charger.  The EBH uses 440 Watts * 3 hours = 1.32 kWh.  That is the same amount that is used by the 120 V charger preconditioning the car for one hour.  The EBH doesn't have to contend with the climate control blowing cold below zero air through the heater core cooling the coolant faster than the 120 V charger can heat it. 

Edited January 12, 2014 at 07:50 PM by larryh

[larryh]

Today, the temperature is 37 F.  Preconditioning only heated the coolant to 16 C, or 60 F, by the GO time.  That's not going to warm the car's interior much. 

[murphy]

Thank you for the above information.  It would be nice if it would record things like MPGe and HVB temperature. 

 

The Davis CarChip Pro only records data when the car is in run mode so it wouldn't work for measuring preconditioning temperatures.

[larryh]

Preconditioning this morning with the temperature at 34 F and using the 240 V charger, the coolant temperature was 38 C prior to the GO time.

Edited January 13, 2014 at 12:05 PM by larryh

[meyersnole]

I saw this article today and thought it might be appropriate to this discussion. Looks like there was a study done on this topic and compares it to similar losses in gas powered cars.

 

http://insideevs.com/infographic-fleetcarma-cold-weather-fuel-efficiency-electric-versus-gasoline-showdown/

Edited January 16, 2014 at 08:02 PM by meyersnole

[Russael]

Cool graphic, but that energy cost comparison left out an important datapoint - how much $ per gallon of gas and a KWH of power to create that scale?  I'm QUITE sure that someone who pays 25 cents per kwh isn't going to get the same payback as someone who's paying 4.  Unless they're just considering averages... but I'd like to see that average number myself.