How to make an electric heater
The most effective electric heaters are made on the principle of a heat gun - the body in the form of a pipe with a heating coil inside and a fan that drives the air through it. This design allows quick removal of heat from the heating element, an intensive exchange of air in the room, good conditions for the work of the helix (decrease its temperature by blowing air).
You will need:
- Nichrome spiral; - Ceramic rod for winding spirals; - Fan; - Galvanized sheet metal; - Electric cables; - Ohm meter; - Bench tools.
Instruction how to make an electric heater
Calculate the required capacity of the heater. At the height of the room no more than 3 m it is possible to determine, based on the calculation of 1 kW to 10 m². To avoid creating too high a load on the wiring, do not make the heater capacity of more than 2.5 kW.
Pick heating coils for the device. Buying it in the store, be guided by the power value. If you are going to use a spiral, where the power is not known, calculate the resistance necessary for you spiral, using the formula R = U² / P, where: R - resistance in ohms; U - supply voltage in V; P - the required power in watts.
Measure the resistance ohmmeter available spiral and compare it with the settlement. If the difference of resistance will be small, use existing spiral. If it is significant, achieve compliance, shortening, or upgrading an existing spiral. At the same time, keep in mind that the series connection of two conductors (coils), the total resistance is equal to the sum of resistances of individual pieces.
Pick of the non-working heater, or buy in the store ceramic element, which will be wound spiral. It should be 250-300 mm long tube with a diameter of the inner hole of at least 7 mm.
Manufacture of galvanized steel pipe (casing) of the heater length of 300 mm and an inner diameter equal to the length of the ceramic tube. The compound housing the junction make folding or with two hoops. As the body can be used and the usual galvanized bucket, cutting off its bottom.
Drill a hole in the wall of the body 6-7 mm in diameter, placing it roughly in the middle. Cut metal bars Ø6 mm and length 50 mm longer than the length of the ceramic tube. Cut at the ends of the thread M6. Push rod (pin) in the housing through the opening in the insulator tube, after inserting the last into the body. Tighten the nut so that the wall of the housing tightly pressed against the ends of the ceramic tube.
Manufacture of strips or bar heater legs. Their shape may be any, as long as they provide a stable position of the heater on the floor and had two pins with the holes Ø6-7 mm. Put a pin on the ends of the pins sticking out from both sides of the body, and tighten the second pair of nuts. This mount allows to install any position of the body of the heater relative to the horizontal.
Wind on a ceramic tube that is inside the body, a spiral. Connect the ends to electric wires by means of bolted connections and wires Output. The ends of the spiral with connected wires must be securely insulated from the body with the help of textolite gasket.
Attach one end of the fan housing. Well suited for fans of the model established in the ventilation grills in homes with forced ventilation. But, in fact, it fits any household fan. A method of fastening it to the body is defined by its structure. At the other end of the housing secure the metal grate to prevent accidental contact of people with a heating coil.
Connect the wires from the coils and the fan, to the plug - in such a way that its inclusion in the socket provided simultaneous operation of the spiral and the fan (in parallel). Check again the insulation quality of the live wires of the heater and switch on the network. Confirmation of correct work done should be the fan noise and warm air blowing from elektropushki body.