Cabin Heater cannot keep up below -20c at highway speeds

[CauliflowerKing]

I don’t know if it’s just my vehicle, but my 2021 MME premium can’t keep the cabin warm below -20c temperatures. Especially going higher speeds when the motors need more power. Is the battery just not able to distribute energy efficiently enough to keep the interior warm? Im wondering if this is a common issue? I really have to bundle up in these cold Saskatchewan winters when I make my daily commute. It’s getting tiring. I have made a service request at my local dealer to look into it, but I immediately received a text back from them saying nothing can be done about it. And then was told to buy an auxiliary heater, which are all terrible quality. Ridiculous. Any suggestions?

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[Deleted member 19354]

May want to out on recirc.

 

[Billyk24]

Mach Lee's write ups go into detail on this issue. In short, there is a lack of insulation below the battery pack. Driving in real winter cold causes a conductive heat loss. The vehicle's heater will prioritize heat to the battery pack over the cabin area. If you have not done so, get an ORB2 reader and app such as the Car Scanner Pro to read multiple vehicle items in real time.

 

[Tomatoboy]

It’s not that the battery is not able to distribute energy efficiently enough, as Billy noted, Mach-Lee has gone pretty deep into the cold weather performance, and the lack of under battery insulation combined with the heater being shared between the cabin and the battery means when it’s super cold and you go fast the heat loss to the battery triggers the car to deprioritize the cabin due to limited heater power. In other words, it’s not an electrical battery issue, it’s a physical design battery pack issue combined with the fact that you are relying on what’s basically a big space heater to keep warm, not waste heat from an engine. Aside using your seat warmers and preconditioning with a departure time on your outbound trip (and unbound if you have charging at work) there’s not a ton else you can do without modding the vehicle but slow down a tad when it starts getting too cold inside, to reduce heat loss. The key is keeping the battery warm before you leave.

Those threads:
https://www.macheforum.com/mach-lees-mach-e-cold-weather-testing-taking-requests/
https://www.macheforum.com/mach-lees-cold-weather-charging-strategies/
https://www.macheforum.com/how-to-remotely-precondition-battery-unplugged/
https://www.macheforum.com/mach-e-thermography/
https://www.macheforum.com/site/threads/2023-5-cooling-system-redesign-and-larger-7-kw-heater.34305/
https://www.macheforum.com/psa-keep-the-battery-warm-so-you-have-enough-cabin-heat/

 

[CauliflowerKing]

It’s not that the battery is not able to distribute energy efficiently enough, as Billy noted, Mach-Lee has gone pretty deep into the cold weather performance, and the lack of under battery insulation combined with the heater being shared between the cabin and the battery means when it’s super cold and you go fast the heat loss to the battery triggers the car to deprioritize the cabin due to limited heater power. In other words, it’s not an electrical battery issue, it’s a physical design battery pack issue combined with the fact that you are relying on what’s basically a big space heater to keep warm. Aside using your seat warmers and preconditioning with a departure time on your outbound trip (and unbound if you have charging at work) there’s not a ton you can do but slow down when it starts getting too cold inside to reduce heat loss.

Obviously this car isn’t built for a harsh Canadian climate. Unfortunately I can’t slow down on the highway without being a hazard.

 

[HuntingPudel]

There are a couple of members here working with @Mach-Lee on insulating the underside of their battery packs and gathering data. ??

 

[Maquis]

Note that later models (23s, I think) had the heater size increased from 5 to 7KW.

 

[Billyk24]

Note that later models (23s, I think) had the heater size increased from 5 to 7KW.

Job 2, 2023 models if I remember correctly.

 

[Billyk24]

There are a couple of members here working with @Mach-Lee on insulating the underside of their battery packs and gathering data. ??

Many of us are awaiting such reports.

 

[Tomatoboy]

Note that later models (23s, I think) had the heater size increased from 5 to 7KW.

Yup. Job 2/2023.5 with the LFP packs, as LFPs are more cold sensitive.

 

[B177y]

@Mach-Lee made a glass roof cover out of reflectix insulation that helps to keep the cabin warmer instead of losing all of the heat through the glass. Might help out your situation:

https://www.macheforum.com/site/thr...-reduce-heat-loss-in-cold-temperatures.26010/

I can't see if you have a glass roof or not on your profile pic.

 

[CauliflowerKing]

@Mach-Lee made a glass roof cover out of reflectix insulation that helps to keep the cabin warmer instead of losing all of the heat through the glass. Might help out your situation:

https://www.macheforum.com/site/thr...-reduce-heat-loss-in-cold-temperatures.26010/

I can't see if you have a glass roof or not on your profile pic.

That would be helpful if there was any heat coming out of the vents at all haha

 

[Maquis]

Yup. Job 2/2023.5 with the LFP packs, as LFPs are more cold sensitive.

I thought they all got it, not just LFP?

 

[Tomatoboy]

I thought they all got it, not just LFP?

Mach-Lee’s original post on the change suggested it was just the LFPs. https://www.macheforum.com/site/threads/2023-5-cooling-system-redesign-and-larger-7-kw-heater.34305/

 

[Maquis]

Mach-Lee’s original post on the change suggested it was just the LFPs. https://www.macheforum.com/site/threads/2023-5-cooling-system-redesign-and-larger-7-kw-heater.34305/

So it is LFP only. On the plus side, that post outlines other heating system improvements that could benefit all models.

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