Bump! So Getting back to this project. I have had all of the parts etc. and a completed design for months. But once we got the recall notice on the airbags I put off going forward. Unlike some of my other mods to the car which are, for all practical purposes, invisible. This one will be obvious, right under the hood. Like everything I do, with something under warranty, the design allows reasonably easy removal with no trace that it was ever added. However in the interest of laziness I wanted to get the airbag done first. Got my wife’s cars airbag done last week and (another story
) I am NOT looking forward to going back to the dealer for my own to be done.
We had a rare day for NM recently so I took the opportunity to do some testing. Conditions were dark overcast and 29 Deg F. I preheated the car at 240 volts input. Then went for a long drive. Dark overcast is important since the sun here at 5000 ft elevation is so powerful. If the sun is out, far less heat is required. Mainly my goal was to measure the best practice usage and resulting power consumption of keeping comfortable. I didn’t dress any warmer than I would for, say a grocery run in an ICE. I don’t like to drive with a coat on (so no coat) no insulted boots, no hat, gloves or anything like that. Just good over the calf socks, summer hiking shoes, jeans and a t shirt under a long sleeve henley.
Doing hiking trips to the mountains for two full winters (this is the third) has helped me find the best most efficient way to use the stock heat. It makes sense when you think about it and is different than we are conditioned to use the heat from years of ICE driving.
Preheat the car if you can.
Use the seat heater. I usually turn it off after ~10 minutes because it gets too hot
Direct the heat to the floor only, on recirculate (it will keep all of you warm, heat rises).
One notch toward defrost if needed to prevent fogging.
Start driving with the fan on high (I like the setting just below high because it is a bit quieter)
Temperature setting should be where ever you need it to be. I generally start high and end up on the second or third position up from the green dot.
If and when the heat is adequate inside the car turn the temperature down, not the fan!
#6 is critical! The heated fluid goes from the heating element right into the cabin. The more heat that you take out of that fluid before it makes the long trip outside of the cabin (under the hood etc.) the less heat is wasted to the cold environment.
So back to my test run. I drove around town town for 1.5 hrs using the Canion heater power graph to average my power consumption for heating. The average for the trip was 638 watts/hr. That (generously) equates to about 3 to 4 miles of worth of lost driving power (per hour) for staying comfortable. I know from previous non preheat trips at around 33F that approximately an extra 800 watts of power is required to warm the car up inside (just the front, heat directed to floor only using the “max” button until the the chill retreats). Which yields ~1500 watts for the first hour starting out cold (up to ten miles worth of range).
The 2014’s have a styrofoam piece under the front carpeting. I don’t think the 2012’s have this and it would make a difference, I’m sure. But overall, if one optimizes usage of the heating built into the car and it isn’t to to cold (29F is reasonably cold though).
The point of my test run was to take advantage of the unusual weather conditions to see if the 1200 watt output of the designed separate battery powered heating unit would be enough. Looks like it should be even capable in worse conditions than I encounter. Perhaps with an initial boost from the onboard system to speed the initial response time of warming the cabin when not preheating from the mains.