Like I said in the introduction, the device will not heat up the car and it may also not be that effective against defrosting since the area from which the air blows isn’t that large (it can partially defrost small areas). The heater in your car is broken and if repairing it would cost more than the car itself, then a device such as the RoadPro RPSL-581 car heater can ensure that the windshield is kept defogged. Important Note: Be aware that all of these devices can become a fire hazard if left unsupervised or if they function next to flammable materials. So, while a small portable car heater may work efficiently on your windshield (more or less), you may still need to feel warm while driving (especially if the heater gets broken in the middle of the winter) and thankfully, there are some interesting solutions out there, such as the heated seat cushions or electric blankets which will be a lot more effective into keeping your body warm. Harbor Freight (RoadShock) 12V Car Heater UPDATE : I have added the Harbor Freight (RoadShock) to the best 12V car heater list RoadPro RPSL-581 12V Car Heater Since the cigar lighter socket is the weak spot, the heater can be hardwired directly to the battery (with a fuse with higher Amperes to protect the wiring) or you can use an inverter (in this case, you need to be careful not to drain the battery – which can happen when the vehicle is stationary and the engine isn’t running). So, one shouldn’t use a 12V car heater under any circumstances? Well, not necessarily. One problem that can arise while connecting a 12V car heater is that the socket comes with low amperage fuses and, if the device you’ve connected isn’t properly made (the cheaper the cost, the lesser the quality), then there is a high chance these fuses will blow or worse, the entire cigarette lighter wiring can become compromised.

Well, at least that’s what we expect it to be, but, unfortunately, this cannot happen because the 12V socket simply wasn’t designed to handle a powerful car heater instead, the maximum we can really get is a simple windshield defogger and, at most, to warm our hands (the maximum power output is usually between 150 – 200W). The best 12V car heater should be able to replace the built-in car heater (at least to a certain degree), being capable to defog and even defrost the windshield, all that while keeping the passengers relatively warm.

12v space heater