Direct Wire Car Heaters
The most common complaint about the plugin style of portable car heater is that it just doesn't produce enough heat. What is the answer?
Well, either to have the heater in your car repaired or to get a good direct wire portable car heater. Fixing your car heater will probably cost between $400 and $600 (depending on where you live)--whereas the very best installable portable car heater costs about $200. (You can also get lesser quality ones for under $100.)
| Flex-a-lite 640 Mojave Heater |
![]() |
Overall Rating: |
| Retail Price: $199.95 |
| Amazon Price: $199.95 |
What is a direct wire heater, you ask?
It is a 12-volt car heater that gets wired directly to your vehicle's battery--and, as a result of that direct wiring, it can produce a level of heat in your car that will do more than just defrost and take the edge off the cold.
Can I install it myself?
A directly-wired portable car heater is a fairly simple, do-it-yourself way to make your ride more comfortable, warm, and safe. The basic installation steps are as follows (and full DIY instructions come with the device, of course):
* Mount heater in desired location
* Run wires through vehicle firewall
* Set heater in the "Off" position
* Connect BLACK wire to the negative (-) battery terminal
* Connect RED wire to the positive (+) battery terminal
How does a direct-wired 12-volt auto heater work?
Like your car's original heater, It draws its heat from the hot water in your car's cooling system. Unlike a built-in car heater, it is compact and easy to install. Whereas the cigarette lighter plugin might be considered a bare-bones emergency fix, a direct wire portable car heater like the recommendation above comes closer to being a replacement solution.
Here's a quick list of the pros and cons of using a direct wire heating device in your vehicle:
Pros:
- Produces a comfortable level of heat.
- Many models have rear seat heating capability.
- It won't blow your cigarette lighter fuse or produce a hot plastic smell in your car.
- Configured for easy hookup: most models have ring terminals already crimped and soldered onto the ends of the hook-up wires
Cons:
- Among the more expensive portable car heater solutions
- There are inferior quality models available at cheaper prices. So, if you're not careful about your selection, you may just end up having to return the item after going to all the trouble of installing. Quite a headache.
- Since you're dealing with your car's wiring, it's imperative for safety reasons that the job be done correctly. While it IS a DIY job, you might just want to ask for help if you're not a mechanically minded person.
Also recommended (though lesser in quality than the model above):
| Flex-a-lite 650 Mojave Plenum Heater |
![]() |
Overall Rating: |
| Retail Price: $59.95 |
| Amazon Price: $56.32 |

