Page 2 of 4

Re: Better heater, less or no loss in range

Posted: Sun Jan 13, 2019 2:36 am
by LeftieBiker
Your idea seems to be a good one. I'm not certain that it would cause a problem if posted in the other topic, but making it more clear removes any objection I had. You can edit your first post to change the title, I think. If not I'll do it later.

Re: Better, Diesel-Fired Liquid Heater for 2011-2012 Leaf

Posted: Sun Jan 13, 2019 6:00 am
by Oilpan4
I think the first order of business is do an experiment to see if the coolant loop can take an additional source of heat added to it. A proof of concept test before I spend the $.

My expectation is that I turn on the diesel coolant heater when the cars normal heater is turned on, both heating apparatus come on, warm up the coolant loop, then the diesel heater stays going and the 380v DC heater drops off and the diesel heater provides all the heat.

Over the years I created multiple 240v based hot water heater element based coolant heaters. I would plumb these into the ICE coolant system. I would start the vehicle to get the coolant flowing then energize the hot water heater element. A 5,500w hot water heater element added before the heater core would almost instantly start thawing ice off the windshield when plugged in.
The first ones were really crude just a 2,800w element and screw together galvanized pipe bits and brass hose barbs. The latest generation used welded 316 stainless steel tube, stainless hose barbs and a 5,500w folded over element. ThE first one was made back about 2006, the all stainless welded version started in 2010.
Since I know I have 1 or 2 of these heaters in my junk collection I would plumb 1 into the leafs coolant loop just to see what happens.

The 2011, 2012 and later sport leaf heater unit appears to contain the heating element and the temperature transducers together in the same unit. So I would want coolant to flow through the diesel fired heater or 240v AC electric test heater before it goes to the leafs existing battery powered heater.

Re: Better, Diesel-Fired Liquid Heater for 2011-2012 Leaf

Posted: Mon Jan 14, 2019 11:27 am
by IssacZachary
I see no reason why it wouldn't work. The Leaf should have some sort of thermostatic control.

How do you plan on testing it? Heating up the coolant going into the heater and seeing if the Leaf's heater stops heating and at what temperature it does so? If coolant starts boiling then you know that it doesn't have a thermostat.

I guess if it didn't have a thermostatic control, you could make some sort of high power relay that shuts off the heater when the diesel heater is on.

I've used those diesel preheaters before on several vehicles. They do a great job at heating engine blocks and even providing heat while the vehicle is shut off. You may be able to get a 5 or 6kW heater for $1,000 new. Maybe even less if it's used.

Re: Better, Diesel-Fired Liquid Heater for 2011-2012 Leaf

Posted: Mon Jan 14, 2019 3:51 pm
by Oilpan4
I'm kind of cheap so I will be looking to buy the diesel coolant heater this summer when no one wants them. Hopefully find a slightly used one.

As long as it passes the 240v AC hot water heater element proof of concept test.

Plumbing in the 240v AC hot water heater element just to see what will happen should tell me everything I need to know.

I don't think I want to several the connection between the DC-DC converter and the leafs original heating element, I'm sure it will throw some kind of fault.

If I can get the leaf to blow out oppressive heat with only a little power going to the leafs heating element I will consider it a success.

Re: Better, Diesel-Fired Liquid Heater for 2011-2012 Leaf

Posted: Mon Jan 14, 2019 8:47 pm
by Oilpan4
Lookie what I found. Searching for something else.

Should I have brought this 2012 topic back to life?

http://www.mynissanleaf.com/viewtopic.p ... 1&p=227745

But it doesn't look like they got very far.

Re: Better, Diesel-Fired Liquid Heater for 2011-2012 Leaf

Posted: Mon Jan 14, 2019 8:52 pm
by LeftieBiker
The search feature at this site doesn't work well, and not everyone even tries a search first, so this happens a lot...

Re: Better, Diesel-Fired Liquid Heater for 2011-2012 Leaf

Posted: Mon Jan 14, 2019 9:34 pm
by OakLeaf
Although it's for an iMiev, this write-up and video series I thought was very helpful in understanding the issues involved with integrating a hot water heater into an EV:

https://300mpg.org/imiev-heater-installation/

Also:

https://youtu.be/6saRb8Fh2gE

Re: Better, Diesel-Fired Liquid Heater for 2011-2012 Leaf

Posted: Tue Jan 15, 2019 1:45 am
by Oilpan4
With the way this is looking I'm thinking about just skipping the proof of concept test and just getting the diesel heater and diving in.
The sooner the better.

Re: Better, Diesel-Fired Liquid Heater for 2011-2012 Leaf

Posted: Tue Jan 15, 2019 1:29 pm
by Oilpan4
I found a range extending heater mod that confirms how I was thinking the heater works.
The mod ties in to the wiring harness and parallels a resistor with the existing thermal resistor to make the sensor read that the coolant in the heater is hotter than it really is.

So the leaf has 2 set points, it has a max coolant temperature set point and the other is the cabin air set point. It hits either one of those and ramps the power tone heater down.
Then I think you can also limit heater power by turning the temperature down to 60F and driving the car in eco mode.

Re: Better, Diesel-Fired Liquid Heater for 2011-2012 Leaf

Posted: Sat Jan 19, 2019 7:56 am
by PaulSp
Not a coolant heater but air heater.. removeable in 1hrs work

http://mynissanleaf.com/viewtopic.php?f ... 0&start=30