Easy Climate Control Fan-Only Solution - 5 cents, 5 mins

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So, did a search on the thread and was amazingly surprised no one has suggested doing method 2 with a simple push-button (always open unless depressed) "latching relay". This gives you simplified install while also working with timer control. The push button is only to engage the relay, that can only be powered while the car is on. That closes the circuit for the 330ohm resistor. When the power goes off, the relay disengages and you are back to stock wiring and ready to engage climate control timer. Way, WAY easier than method 3. You can also get fancy and buy an illuminated switch that is wired to the relay power to have a visual indicator of on or off.

If your not familiar with a latching relay, basically you use the 12v power that would be used to power the switch also loop through the relay switch and back to the coil +, that once engaged, keeps the relay on. The relay will not disengage until 12v supply is lost (car off). if you want to manually disengage the relay, you install a normally closed push-button switch that temporarily breaks the 12v supply to the relay. Normally closed push-button switches are always closed while disengaged, and broken only while your finger is depressing.

So effectively, you have the best of both worlds without the solder and loss of time.
 
Supersleeper said:
So, did a search on the thread and was amazingly surprised no one has suggested doing method 2 with a simple push-button (always open unless depressed) "latching relay". This gives you simplified install while also working with timer control. The push button is only to engage the relay, that can only be powered while the car is on. That closes the circuit for the 330ohm resistor. When the power goes off, the relay disengages and you are back to stock wiring and ready to engage climate control timer. Way, WAY easier than method 3. You can also get fancy and buy an illuminated switch that is wired to the relay power to have a visual indicator of on or off.

If your not familiar with a latching relay, basically you use the 12v power that would be used to power the switch also loop through the relay switch and back to the coil +, that once engaged, keeps the relay on. The relay will not disengage until 12v supply is lost (car off). if you want to manually disengage the relay, you install a normally closed push-button switch that temporarily breaks the 12v supply to the relay. Normally closed push-button switches are always closed while disengaged, and broken only while your finger is depressing.

So effectively, you have the best of both worlds without the solder and loss of time.

A sealed-in relay (not a mechanically-latched relay) would work as you describe, however you need to remember to depress the momentary pushbutton each time you start the car. The plug-and-play kit with 2 resistors and 3-position switch is a better and simpler solution if you want to make sure the heating element stays off unless you really want heat. The kit also gives two levels of heater temperature.
 
GerryAZ said:
A sealed-in relay (not a mechanically-latched relay) would work as you describe, however you need to remember to depress the momentary pushbutton each time you start the car. The plug-and-play kit with 2 resistors and 3-position switch is a better and simpler solution if you want to make sure the heating element stays off unless you really want heat. The kit also gives two levels of heater temperature.

I assume you mean solid-state relay? I haven't seen any switches that would have that built in, but I'd love to get my hands on one if they did exist. I just went ahead with a basic latching switch for now. I may later change to something else.

Yeah, I agree, if you are not electronically inclined, the harness is the best solution. I just can't see myself paying $150 for a cable, a resister and a switch. It's like $1.50 worth of material and 999% profit. It is worth the convenience to be able to revert to stock without having to tap into the wires, but this is a 6 year old car, and I personally don't care to revert to stock ;).
 
Since I rarely used the heater, I inserted a resistor directly into the connector under the hood and wrapped it with self-fusing tape to keep the heater from drawing power while using the air conditioner.

The kit I was referring to is the one by TorC (there is another thread about it) that costs about $20 US. The kit includes a harness with connectors on both ends that plug between the factory harness and HVAC controller so there is no need to cut into the factory wiring. I would have purchased the kit from TorC if my 2011 Leaf had not been totaled.
 
@ Supersleeper
Well, your idea is very good, and I have considered it in the past. One problem with the "method 2" (and my cable kit) is that you will not be able to use pre-heat with timer or App if the switch is engaged.

My solution to this is to simply use a N.O. relay connected to a switch both powered by the 12v outlet.

The switch will "remember" last setting, but will be inactive when the car is ON.

I do have a "plug and play" solution in the pipeline, but have been struggling for 9 months to get the correct connectors/terminals to the Nissan LEAF harness. I am now on the last possibility before I have to "backsource" the final assembly, but that will drastically increase the price due to local taxes and labor cost.
 
I did the mod (version 3), and it *seems* to work, but when I start up climate control without heating it still says it's using a couple kW, yet the air blowing out of the vents is cold. Is this normal? Does this mean the Leaf doesn't actually measure energy use, but rather estimates it based on what it thinks it's doing?
 
mux said:
I did the mod (version 3), and it *seems* to work, but when I start up climate control without heating it still says it's using a couple kW, yet the air blowing out of the vents is cold. Is this normal? Does this mean the Leaf doesn't actually measure energy use, but rather estimates it based on what it thinks it's doing?

Yes, for the climate system and some other things. Headlights, wipers, and various smaller loads are estimated.

Driving and regeneration power is directly measured, but accuracy isn't great.
 
mux said:
Does this mean the Leaf doesn't actually measure energy use, but rather estimates it based on what it thinks it's doing?
WetEV said:
Yes, for the climate system and some other things. Headlights, wipers, and various smaller loads are estimated.
Are you looking at the Energy Usage screen?
usage-energy-economy.jpg


The Leaf uses a lookup table of estimates for things in the "Other Systems" display, but "Climate Control" is measured. I performed mod #2, and when I have the AC turned off and my added heater switch off, Climate Control shows no energy usage at all.
 
Yeah, on that screen I still see energy use, but no hot air. I'll have to test it a bit more to see what's really going on. Might have to use the thermal camera (thank god for that invention)
 
After driving with this mod for almost two weeks, it indeed seems to work just fine. The car seems to think it is much warmer than it really is, by about 10 degrees, which means I still get some heated defrost when it's below freezing but the heating quickly stops. The AC button still works to make everything function like normal.

So it's a success!
 
BetterLeaf said:
The Nissan Leaf's climate control unit does not allow you to run the fan or switch to window defrost/defog mode without automatically turning on the battery draining heater.
In humid or cool weather it is desirable to run the fan at a low setting to keep the windows clear.

Here are three different alternative methods to allow you to run in fan-only mode.

All of the variants below rely on the same underlying principle:
They trick the climate control module into thinking that the heater fluid is already heated up to around 160F (70C). So it no longer turns on the PTC heater. No energy is wasted when running the fan or switching to defrost mode. The rest of the system will continue to operate normally.

Method 1: No heater switch.
Pros: Super easy, 5 cents, 5 mins, no tools or experience required, fully reversible
Cons: Heater remains always off.

Method 2: Separate Switch for Heater.
Pros: 20 to 50 mins, screw driver, no soldering required
Cons: Wire taps, location for separate switch required, pre-heating requires switch in off position

Method 3: A/C switch also controls heater.
Pros: No visible changes, no wire taps, no additional switch.
Cons: 50 to 90 mins, soldering required.

If you decide to implement one of these methods you are doing so at your own risk!

Best method yet!!! sometimes we need little heating to ocour!
Method 4: Separate (Switch AND/ OR no switch ) 1K-oom Potensiometer aka "resistor trimmer" for Heater.
Pros: 20 to 50 mins, screw driver, soldering required, You can regulate exatly Heater POWER consumption!
workind with ohters first GEN elektric cars mudels too, like iMiev, iOn, ZOE!
Cons: Wire taps, location for trimmer resistor required, pre-heating requires trimmer position hole in dash somwhere

You need lower water temperatuure, it helpful, slower water cooling will accour, and less energy needed for heating, and less power wasted, in fron of the car, where no tubes are isolated:

50868912_10205299350759210_2966342927036448768_n.jpg


https://www.youtube.com/watch?v=OWIQDe6tqp8

49196518_10205225217345921_5407514871073865728_n.jpg

48373779_10205177123983617_9119419959842177024_n.jpg


Nissan LEAF heats water to 70*C and this is uses to mutch bateery energy, 5KWh!
when I turn added trimmer (POTE) to half, then I dont let water heat to 70*C, but letting water temperatuure only rise to 55....60*C, even 60*C car is worm and I loose only 10km with 100km, if outside temperature below 0*C
Lower temperatuure - lower heat lost! lower temp even 5% - gives 20% less heating energy vasted!
I gained allready more than half heating power over 100km, holding heating power below 1,5kW, but car inside temperatuure is normal like 15*C in winter.
2011-nissan-leaf-energy-display_100317784_m.jpg

even no ON/OFFf button not needed enaymore, I can turn trimmer putton to 0 position, and heating power allways 0.

I even put addional relay, for pre heating from android nisan APP for preheating, then car heats in full power with app and when charging cable is on. This additional relay (R) is not needed in warmer climate! Relay for most robust and for faster preheating.

48310036_10205170813385856_3104230846324801536_o.jpg


48362805_10205173202045571_5628783387071217664_o.jpg
 
with potenciometer hack, I made connection in coling and heating water systems, and now cooling water goes trough salong radiaator and in cabin already wormer

Now I dont allow water heated 70*C any more, but only to 30*C, and win -1 I have 18*C temp in cabin.
55606168_10205529714398157_4891156164533813248_n.jpg
 
reneek24 said:
with potenciometer hack, I made connection in coling and heating water systems, and now cooling water goes trough salong radiaator and in cabin already wormer

I changed heating thermostat potenciometer with 470ohms, and this to not alow preaheating goes over 30*C. I can use 5kW heater, when needed.

Now I dont allow water heated 70*C any more, but only to 30*C, and winter -1 I have 18*C temp in cabin, without using big 5kW heater.
instead I placed 2 PTC 400W elements from 12V system in feet outleet and I use ownly 800W energy to heat cabin
It Works even with -8*C
 
Wow. Was this tread both super informative and also, well I must admit it, I don't think I understood anything other than the fact that using the Leaf's heater is a huge drain on our battery and driving range.

So, having said that, I'm a proud new owner of a 2014 Leaf SV. I believe my most frequent use of the cars climate control would be to heat the car when its very cold out some mornings, when the windows fog up for some reason and I need to be able to see when driving, and then when its hot outside and I need to use the A/C some.

Can someone please let me know if the modifications talked about throughout this 16 page thread is definitely something that I need to show to a car electronic guy and have them do? Or are there some other ways that I can use the existing car system without significantly reducing our driving range. BTW - I already know and have been using the steering wheel and seat heaters in the morning when its been like 40 degrees here, and wearing jackets, we're just fine.

Thank you. Please, in the simplest terms of what, if anything, I need to get done so we can go far as possible in our great new to us car.
:D
 
To go as far as possible: drive slowly and don't use any climate control. Practically speaking, on a 2014 SV don't worry about it. When the temps are very low (< 30F) the resistance heater will come on and use quite a bit of power. Putting the car in ECO mode will limit that somewhat but when it's cold - it's cold. An ICE car wastes a lot of energy in the form of heat so when it's cold it seems like the heat is 'free' but in reality, that heat is always being generated whether it is needed or not. Same for the AC. It will use some power but not much. For some reason, I think the electrically powered AC on a Leaf is more efficient than the motor driven AC on an ICE car. You can watch your kWh/mile to get an accurate measurement but I wouldn't bother to skimp on AC if you need it. It doesn't take much power. In fact, when the weather is warm but not hot, it's actually more efficient to keep the windows closed and run the AC rather the open the windows when going highway speeds. The aerodynamic gain from having the windows closed out weighs the power used by the AC.
 
Can someone please let me know if the modifications talked about throughout this 16 page thread is definitely something that I need to show to a car electronic guy and have them do?


The heater switch modification is for pre-'13 Leafs - you already have a vastly better heating system. Here is a collection of driving tips:

https://www.mynissanleaf.com/viewtopic.php?f=38&t=23297&p=482154

When the temps are very low (< 30F) the resistance heater will come on and use quite a bit of power.


The resistance heater runs when you start the heat even in milder temps, in order to speed heating of the cabin. It also starts to supplement the heat pump (in Leafs so equipped) at temps somewhere in the upper thirties to low forties, IIRC.
 
Thank you to all who responded. Definitely comforting to know that my '14 doesn't experience the same problems of an older model. We love this car and honestly do not plan, nor do we have to drive it when the temperature here in Atlanta is below freezing, so maybe the only issue that we will have to deal with is when we're using the car during the brutal Summer months. :)
 
Does anyone have the pictures on page 1? I want to do this mod but can't without seeing what they are talking about.
 
The Wayback Machine to the rescue!

https://web.archive.org/web/20160512142257/https://www.mynissanleaf.com/viewtopic.php?f=37&t=11412

Perhaps a moderator could edit the original post to link to the same images hosted elsewhere, although that would take a bit of work...
 
alozzy said:
The Wayback Machine to the rescue!

https://web.archive.org/web/20160512142257/https://www.mynissanleaf.com/viewtopic.php?f=37&t=11412

Perhaps a moderator could edit the original post to link to the same images hosted elsewhere, although that would take a bit of work...

Post a link to the version with no images and I'll take a whack at it later.
 
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