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Discussion Starter · #1 · (Edited)
I still need to verify by running some more. But if today's test is an indication this very well may be a solution to increase the winter range.

25-degree weather, sunny, clear roads. Typical I would see 2.6-2.7 Miles/kWh 35-65 miles per hour. (mostly speeds above 50).

Today with my setup I got 3.3 Miles/kWh

But my REAL surprise was just in town driving 35 miles per hour, maybe 7 stop lights/stop signs over 10 miles I got 4.2 miles/kWh !!



The entire test was 44 Miles. Heated Seats and Heated Steering wheel off the entire time


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Brand New with Remote...$10 I'm giving myself a (y) on that purchase

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Discussion Starter · #2 ·
BTW.. the last 5 miles I turned the little heater up to 800 watts from 400 watts to see how that would affect range. Didn't seem to make a difference. 4.2 miles/kWh at 400 watts and same at 800 watts..Of course, that was just 5 miles. Just wanted to post that before I forgot about it.


I need to find a place on the firewall to run the power cord through. Looks at the passengers side under the glove box. I may run that over to my mechanic and have him raise the car up on the lift, drill me a hole, and put a grommet in. just not looking forward to crawling around on the cold garage floor trying to do that myself when he can do it in 5 minutes.
 

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I need to find a place on the firewall to run the power cord through. Looks at the passengers side under the glove box. I may run that over to my mechanic and have him raise the car up on the lift, drill me a hole, and put a grommet in. just not looking forward to crawling around on the cold garage floor trying to do that myself when he can do it in 5 minutes.
There's already a rubber grommet on the driver's side that some of the radio and speaker guys have used by punching a hole in it.
 

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Long ago, when the '11 and '12 Leaf (not ones afterward) also had a power pig water heater like Bolt, folks have talked about insulating the heater coolant hoses and the bottle (e.g. How to Insulate Heating and Coolant Pipes in 2011 2012 Nissan LEAF and Insulating the heater on MY11 - My Nissan Leaf Forum). I never had that version of Leaf as my 1st and current one are a '13 SV w/hybrid heater w/heat pump. There's no more heating of coolant to run thru a heater core and hasn't been AFAIK after model year '12.

Besides dressing warmly, others have talked about 12 volt electric blankets and 12 volt heaters like 12V Auto Heater / Defroster with Light. I've never done either but the comment at Defogging windows? - Page 2 - My Nissan Leaf Forum indicates the Harbor Freight 12 volt heater at the time was useful as a foot warmer. There's only so much you can do with 13 amps * 12 volts = 156 watts... (Well, might be a bit more since 12 volt buses usually run higher than exactly 12.0 volts.)
 

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It's too bad the Bolt heater wattage doesn't seem to vary with the heater setting. Not that the heater ever needs to be turned down. It's probably one of the worst heating systems ever designed for any car. Literally putting a space heater in the front seat is a significant improvement.

The heated seats and steering wheel use very little power. The GOM does not decrease at all when they are turned on. I find those to be among my favorite features of the car and would not stop using them.

According to the GOM, turning on the heater reduces range by about 10%. If your theory (2.7 vs 4.2) is correct, the heater is reducing your range by 36%. Either your theory is way off, or the GOM is way off. Definitely test more.

After my recent incident when the 20 month old 12V battery went bad and stranded me 300 miles away, I would not toy with the 12V system (the battery and its associated DC-DC converter) by drawing an additional continuous 400 or 800 watts from it. At the very least, you might think about getting a battery voltage monitor and keep tabs on it. I recommend one like this.

Jebsens 4.8A 24W Dual USB Car Charger Volt Meter Car Battery Monitor with LED Voltage & Amps Display, for iPhone 7 / 6s / Plus, iPad Pro/Air 2 / Mini, Galaxy S7 / S6 / Edge/Plus, Note 5/4
 

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The cabin heater wattage does vary. It doesn't matter even it is just going on or off.

I can see a resistance heater has higher efficiency. 100% of the energy goes to heat up the air in the cabin. The coolant hoses always leak heat. But the key question is whether a 800w resistance heater in the cabin is as comfortable as a 7.5 kw coolant heater going say at 3 kW. It works if it is.

Would you show us the resistance heater?

-TL

Sent from my SM-N960U using Tapatalk
 

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Discussion Starter · #7 · (Edited)
It's too bad the Bolt heater wattage doesn't seem to vary with the heater setting.

I was literally just thinking the exact same thing. Control the car's heater by watts...via knob control. Turn up 200 watts, 4000 watts, 600 watts ....

Using a LOT less energy simply by finding a comfortable setting and leaving it at that wattage ..at 25 degrees outside looks like 400 watts is all that is need to get the cabin long sleeve shirt warm ...

The way the Bolt is set up now you can have the heat set at 70 degree and using teliks app I can watch the watts bounce around from 0 watts to 4000K watts, to 3800 watts, drop to 2,000 watts ..ride to 2,800 watts, drop to 800 watts, drop to zero, jump 1600 watts.It's all over the place


I've been up since 1:30 am..going to try and call it a night. Have to stop at Menards get me some correct cables for the inverter and thanks to X12 looks like the threading the power cord through the firewall won't be an issue. So I should be able to get some more testing down tomorrow.
 

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Discussion Starter · #8 ·
The cabin heater wattage does vary. It doesn't matter even it is just going on or off.

I can see a resistance heater has higher efficiency. 100% of the energy goes to heat up the air in the cabin. The coolant hoses always leak heat. But the key question is whether a 800w resistance heater in the cabin is as comfortable as a 7.5 kw coolant heater going say at 3 kW. It works if it is.

Would you show us the resistance heater?

-TL

Sent from my SM-N960U using Tapatalk
It's out in the car , I'll grab photo and specs tomorrow but it looks almost identical to this...these small ceramic heaters. They are good 50 sq ft or so.

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Keep in mind if you watch the video you will see I have a plexiglass barrier between the front and back. Covid sneeze/ coughing shield since I run Uber/Lyft. So the front gets hotter/warmer faster and is about 10 degrees warmer than the back. The plexiglass is not a "complete" barrier there is still air transfer to the back.
 

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What was the mod?

I always wondered why EVs don't use simple space heaters instead of the more complicated and slower method of heating water first and then heating the air.

If I were to build an EV from scratch, I'd probably install radiant heaters for the legs and in the ceiling, with a space heater for the windshield defrost.
 

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I always wondered why EVs don't use simple space heaters instead of the more complicated and slower method of heating water first and then heating the air.
Might be a safety thing. Every space heater I've seen has a warning about not having anything combustible within 3 feet. Kinda hard to do in a car.
 

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Perhaps you could use a 12 VDC heater and skip the DC to AC conversion - such as RoadPro RPSL-681 12V Direct Hook-Up Ceramic Heater/Fan w/Swivel Base
 

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Part of the problem with the Bolt heater is that the AC always comes on too, so they are fighting each other to give you that nice southwestern dry air. Even in mild central Virginia, when the heater is drawing 3000 watts, the AC is drawing 1200 watts.

Yellow Text Colorfulness Line Font


Running heavy wires to the 12 volt battery through that floor grommet with eyelet ends to allow using the battery clamp bolts, and a fuse, and you can hang this 800 watt heater under the dash. Run recirculated air. If the windshield starts to fog, run outside air.

 

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This is an interesting idea, and is reminding me of something I've seen on MyNissanLeaf.com. Some Nissan LEAF owners have dead heaters (especially the 2011/2012 years). One "fix" was to mount a $10-$15 PTC heater element over the defog air vent (see Amazon item B07KJ6Q6QH as an example). Somebody mounted it right to the dash; someone else added spacers.



The faster you blow the fan, the more current they draw, but one over each vent would draw 400W max. There's a video of someone doing this on YouTube: https://www.youtube.com/watch?v=GoMfFfVwN2c
...though I would have to think about how to wire them.

One person reported that it defogged/defrosted faster than the stock heater. I'm not sure how well it would fit with the Bolt's windshield angle.
 

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I always wondered why EVs don't use simple space heaters instead of the more complicated and slower method of heating water first and then heating the air.
Your question should be amended to ask why some EVs heat water which then is used to heat air. Leaf stopped doing that after model year '12, for example.

We got some confirmation of this that I posted about at 2013+ Leaf heaters vs. pre-MY13 - My Nissan Leaf Forum and someone else confirmed.
 

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I can see using either a heat pump like the LEAF SV/SL, ID.4, mY, or direct PTC elements like the LEAF S.

(Though I would suggest putting a separate PTC element right behind each vent, in a way that lets you pop out the vent cover and replace the element. Or otherwise making them accessible.)
 

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Your question should be amended to ask why some EVs heat water which then is used to heat air. Leaf stopped doing that after model year '12, for example.

We got some confirmation of this that I posted about at 2013+ Leaf heaters vs. pre-MY13 - My Nissan Leaf Forum and someone else confirmed.
The heater core approach is legacy from gasoline cars. Engine coolant is hot. It is irrelevant in EV unless it is to harvest the heat from the drive train. But bolt is not doing that. The drive train loop just dumps the heat through the radiator. It is a bit silly.

-TL

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Part of the problem with the Bolt heater is that the AC always comes on too, so they are fighting each other to give you that nice southwestern dry air. Even in mild central Virginia, when the heater is drawing 3000 watts, the AC is drawing 1200 watts.

View attachment 32613

Running heavy wires to the 12 volt battery through that floor grommet with eyelet ends to allow using the battery clamp bolts, and a fuse, and you can hang this 800 watt heater under the dash. Run recirculated air. If the windshield starts to fog, run outside air.

It is annoying, not to mention the AC seems to chill the battery loop too. The guy who designed this must be smoking something. I always manually turns off the AC during winter and leave the rest automatic.

-TL

Sent from my SM-N960U using Tapatalk
 

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Discussion Starter · #18 ·
Perhaps you could use a 12 VDC heater and skip the DC to AC conversion - such as RoadPro RPSL-681 12V Direct Hook-Up Ceramic Heater/Fan w/Swivel Base
Morning Mike, Yeah I looked at all the 12v directs and most of the reviews including the RoadPro look like this ..

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I dont know why it is but all the 12volt stuff is junk.


Also I purchased the Inverter for $10..might as well use it .
 

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Discussion Starter · #19 ·
Part of the problem with the Bolt heater is that the AC always comes on too, so they are fighting each other to give you that nice southwestern dry air. Even in mild central Virginia, when the heater is drawing 3000 watts, the AC is drawing 1200 watts.

View attachment 32613

Running heavy wires to the 12 volt battery through that floor grommet with eyelet ends to allow using the battery clamp bolts, and a fuse, and you can hang this 800 watt heater under the dash. Run recirculated air. If the windshield starts to fog, run outside air.

Morning GJTSEN... Thanks for posting your numbers I forgot to upload mine yesterday but they look almost identical..battery temp 55 degrees, 3000 watts on the heater (and bouncing around all over the place)...and yes I always forget to include the AC watts...geez another 1200 watts ...



Also ... for anyone looking for an Inverter this Sunforce inverter the best review on amazon was this post..


First let me correct a mistake in other reviews that comes directly from the manual. There are two receptacles on the front panel. Some reviewers have stated (and the manual also says) that the load is divided between them and cannot all be drawn from a single outlet. That is false. I opened the unit up and examined the wiring and the two outlets are wired in parallel and do not have so much as a fuse or circuit breaker between them. I also have drawn over 1 KW from the unit from a single outlet. That one piece of mis-information initially kept me from ordering the unit.

My initial testing was done with a heat gun as a load. I tried four settings
1. Inverter switched off - Current draw was unmeasurable. (less than .001 A)
2. Inverter switched on, but heat gun switched off (idle inverter current 1.2 to 1.5 A)
3. Heat gun on low, drawing approximately 550 W (current approximately 50 A)
4. Heat gun on high, drawing approximately 1000 W (current approximately 100 A)
I also monitored the output waveform for the last three cases and it was indeed an accurate sine wave (contrary to a label on the bottom of the unit). It should be noted that the heat gun on low power draws current primarily on only one half the AC cycle, and this did not interfere with the operation of the inverter, or noticeably alter the voltage waveform, which speaks well of the unit. I am sure such a load would adversely affect the output capacity, though.




I suspect once we get back to REAL cold like 5-20 below zero the 800 watts on the heater won't be enough and I'll have to supplement with the Cars heater.. we will see. For NOW, that's ok though.

I'll have it wired up correctly today and run 2-3 hours and then I'll have it on all day tomorrow (Monday) , that will be the real test
 

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Morning Mike, Yeah I looked at all the 12v directs and most of the reviews including the RoadPro look like this ..

View attachment 32617



I dont know why it is but all the 12volt stuff is junk.


Also I purchased the Inverter for $10..might as well use it .
Perhaps that model is junk, but I was just using it as an example. 12 VDC technology works well, I had aux electric built into my Gen 3 Prius and my MB diesel has aux electric heat. You may ask why a diesel needs aux electric heat - for safety. The diesel engine heats up slowly or not at all at idle so the windows can't be cleared, so electric heat is applied until the ICE comes to temp.
Point is 12 VDC heat has been used widely in the auto industry
 
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