Mini electric heater 12V 80W

In this master class I will show you how to make a small electric heater that runs on 12 volts and consumes 80 watts of power. It gives a nice warm breeze which is enough to warm your hands. The mini heater is very easy to make; it can be made from a computer cooler in less than 30 minutes.

Heater Parts and Tools

Parts you will need:

• Computer fan 12 V, with dimensions 40x40x10 mm.
  
• Wire for connection, at least 1 square millimeter in cross-section.
  
• About 1 meter of thin nichrome wire can be taken from a burnt hair dryer.
  
• Approximately 15 cm of thick copper or steel wire.
  
• A piece of sheet metal, about 40x160 mm. You can take it from a tin can.
  
• 4 screws with nuts for fastening to the fan.
  
• Insulating tape.
  
• A piece of wire mesh.

Tools you will need:

• Soldering iron with solder.
  
• Hacksaw.
  
• Multimeter.
  
• Lighter.
  
• Screwdriver.

Making a heating element

Before you start making the heating element, you need to select the size of the nichrome spiral to ensure even heat distribution.
I cut pieces of the spiral and measured the current of each. Initially, I chose the distance where to cut by measuring the resistance of approximately 8.6 ohms. As a result, each section will consume approximately 1.4 A of current. There will be five such segments and the current will ultimately be slightly less than 7 A. I do not take the fan into account.

After preparing the spirals, we proceed to making holders for them. They are made from thick wire. We bend such squiggles as in the photo.

We try on nichrome spirals for them so that when installed they are at some distance from the fan. And they didn’t touch anything except the ends.


We fasten the holders to the fan with screws.

We put on all the heating coils.

Solder the connection points. Solder using active flux, since nichrome practically cannot be soldered.

Connecting wires

We strip the fan wires and connect them to the heating element, clamping them with screws on both sides.


From the other side we pass the power wire through and connect it to the heating element on the other side.


To test the operation of the heater with a fan, we will use a powerful power source. I took the battery. We connect and measure the current consumption. As calculated, it is about 7 A. All elements are heated evenly, blown with air from a fan and hot air comes out.

Heater body

The body can be made from tin from cans. Take a sheet of metal and cut a 4x16 cm strip from it, bend it into a 4x4 cm square. Then solder everything with solder and the case will be ready. Make sure the fan fits into the case.


You can take the mesh or solder it yourself from pieces of wire. We take the dimensions according to the body. We insert the mesh into the body and solder it in the same way.


To keep the entire heating element tightly, you need to wrap the fan in a circle with electrical tape, it will add density. And forcefully insert everything into the body.

Ready-made small heater

Our mini heater is ready. In principle, it seems almost safe to me, but you shouldn’t leave it unattended.



Total power is about 80 W. This heater can be used in a car. Take power from the cigarette lighter socket. Of course, you can’t warm up the interior with it, but you can warm up the windshield or your hands.
I hope you liked my DIY. If you have any questions, please leave them in the comments. See you again!
Original article in English