AC runs on 12 volts or High Voltage Battery

Any one has any idea , if the AC & Heater run on 12 volts battery or High Voltage Battery ?

Just curious
If it runs on 12V , then it needs to have a decent size DC to DC charger for the 12 volts

If you don't have these manuals and want to learn more about an i3, download the series of i3 manuals here.

The 08_I01 Heating and AC Systems manual states that the AC compressor is powered by the high-voltage system. In BEV's, the same compressor is used for heat pump heating. For REx's, high-voltage resistance heating is used. At very low temperatures, the BEV's heat pump system becomes quite inefficient, so it is augmented by the same resistance heater used for all heating in REx's.

So the DC-DC converter does not need to have a high capacity because 12 V loads aren't much different, if at all, from ICE vehicles.

Art,
Thanks for posting the link to the service manuals. I haven't seen those before.

theothertom said:

Thanks for posting the link to the service manuals.

Click to expand...

Unfortunately, they're not service manuals. They're just training manuals describing various i3 systems in some detail but without diagnostic or repair information. Still, better than nothing.

No i3 service manuals or CD's/DVD's are available for customer purchase unlike every other car I have owned. Apparently service information is available online by (expensive) subscription. I have been tempted to pay for a month's subscription to see whether I might be able to download i3 service manuals.

FWIW, I'm pretty sure that if you have the subscription, you can print information...the service manager printed out a couple of pages for me when I had a question.

Rather than trying to keep paper copies of the manuals up-to-date...BMW relies on electronic copies so they know it contains the latest information.

Any idea , how much would be the power of the DC to DC inverter.
Like in case of a power failure and emergency , how much can we draw from the 12 V battery ( when the car is ON/START ) .
I have heard leaf owners use a 1000 VA inverter to power refrigerators etc.

The 12vdc battery in the i3 is closer to a motorcycle sized battery than one normally used in a car. It is used essentially to power the computers and lights (with assist from the high voltage batteries). IOW, it's not big, nor would it support much of a load, nor does the DC-DC converter need to be very large, since the load on it is small. Now, if you could somehow use the LiOn battery to run an inverter, you'd have a lot of capacity. FWIW, BMW has shown a prototype home power pack made up of used i3 batteries and an inverter. ANd, they have installed some larger systems with multiple packs for load leveling in a power distribution situation. When they're no longer viable for use in a car, they still have lots of life left for use in power grid applications.