Climatronic will act as a auxiliary heater?

So I'm rather confused .. I've been googling a bit after i realized i had no power outtake inside my car to connect an external cabin heater, but i did read that as long as i have a 12v cable hooked up to the front of the car then the climatronic in it can be made to act as an auxiliary heater instead, but I've been unable to find more info on it.. So .. Anyone know anything about this? Because I'd love to come out to my car in the morning, disconnect the 12v and heave a preheated car, engine and cabin alike, the engine heater is default from what i understand with the RS (which is what i have).