Download the hair dryer diagram. Electric hair dryer. Types and device. Work and how to choose. Let’s talk separately about options for modifying various elements of the tool’s design.

When your fiancée's hair dryer stops working, it can turn into a tragedy...

Of course, you can please your beloved by purchasing a new one, but believe me, if you undertake to repair the old one and succeed, you will not only save your household budget, but also increase your status as an owner, husband and jack of all trades!

Of course, for many, repairing such devices will not cause any particular difficulties due to their own experience and knowledge, but not all are such fixers!)

Now, using a live example, let's look at some typical faults this type of technology, and those who have never encountered similar works, they will see that there is nothing overly complicated in this. Of course in different devices There will be differences, but the principle is the same.

The first thing you should pay attention to is the power cord; often the wire breaks either at the base of the power plug or at the hair dryer handle itself. Moreover, a broken wire may visually appear to be in good condition because it is covered with rather thick insulation on top.

Such a malfunction is often detected by the fact that by bending the wire in the above places, the device can work. But make no mistake, operate with such a wire electrical devices This is not possible, the wire must be replaced.

To do this, you will have to disassemble the hair dryer, but this will also be needed to troubleshoot other problems. Let's get started.

How to disassemble a hair dryer

As a rule, all modern hair dryers, as well as others household devices of this kind, the mounting bolts are not always accessible and visible; they are often hidden behind various plugs or plastic panels which need to be unfastened. The patient for this article, an old Rowenta hair dryer, is no different in this sense.

Unclip and remove the plastic panel on the hair dryer handle

Using a thin flat screwdriver or better yet a short mounting knife, press the latches and remove the cover. Next you need to disassemble the mechanism for switching the speed mode. To do this, remove the switch wheel axle and remove the bar.

Then we remove another cover and only now can we unscrew the fastening bolts.

By the way, for this you often need a cunning screwdriver, such as a triangle, an asterisk, or a flat one with a slot; in my case, this is a homemade product made a long time ago from an old flat screwdriver, but now you can buy these.

Now that the two screws are unscrewed, complete disassembly It is necessary to remove another plastic part of the case.

Now, you can replace the wire and perform any other repairs.

What was the cause of the malfunction

In my case, the heater shutdown button was broken. Do you know what this button is for? Many, as it turned out, are not aware. The fact is that if you turn off the hair dryer immediately, without using this button, then there is a risk of damaging the device. This can happen because the fan immediately stops after turning off, and the coil has not yet cooled down, the heat has nowhere to go, the hair dryer overheats, and you can even melt the body. And this button allows you to turn off and blow through the coil while the fan is running, giving it the opportunity to cool down somewhat.

So this very button failed, the fastening of one of the contacts broke, so the hair dryer only blew cold air. To repair it, I had to slightly widen the hole of the torn contact and, putting it in place, melt it with plastic to fix it. Of course, before this it would be correct to clean the burnt contacts.

In general, after these simple steps (it takes much longer to describe than to do), the hair dryer worked properly.

What other problems can you fix yourself?

Check the integrity of the power cord, plug, quality of connections, soldering. The button itself can also, if necessary, be disassembled for cleaning, but this must be done carefully so that the contacts and spring do not jump out (used in some buttons). If the button is seriously malfunctioning, it will already have to be replaced; this may not be possible due to the fact that it just can't be found.

The fan motor and the spiral itself are also poorly repairable - if they malfunction, either professional intervention is required, or...... Long live the store!

Another one possible malfunction repairable - thermal fuse.

This is a self-resetting fuse that turns off the heater coil when overheated, and after cooling it returns to its original, closed position. But it happens that its contacts burn out over time and it stops working normally. Needs to be restored good contact, carefully use something thin (a nail file works great, as long as your wife can’t see) to rub between the contacts, but do not open them more than the thickness of the file. Otherwise, you will then have to bend the contact plates to compress them well.

Sometimes tucking is simply necessary. But be careful, it’s not that simple, remember that everything is attached to a fragile mica base and putting in effort can only make things worse.

Remember that with any repair, care and accuracy are important! This is one of the keys to success!

Repairing household appliances sometimes costs a pretty penny, so many are ready to do self-study this topic in order to save money on the family budget. And with a competent approach, quality will be guaranteed.

Hair dryer repair: design features

Despite the apparent complexity, it is quite possible to repair a household hair dryer without the help of professionals. You need to arm yourself with theoretical knowledge about internal structure device and necessary tools.

The device with which we dry and style our hair is simple.

The body is 2 plastic containers, fastened together with screws. Some models use special latching brackets instead of such fastenings. The trick is that such elements have no practical use and are most often a conditional fastening. The fan is one of the main components.

The function is:

• Cooling of heating parts;
• Closing the power supply circuit for the coils in the device;
• Starting the engine.

The electric motor is a low-voltage collector motor based on a single diode (as in Scarlett) or in more expensive models (such as Remington or Babyliss) - a diode bridge that provides voltage rectification and is attached to the motor contacts in the form hinged mounting. A capacitor is used to match the batteries, or an inductive coil does this.

Common complaints when repairing a hair dryer

It happens that when you try to turn on the hair dryer, the device does not start and the engine does not start. Or after a short operation the hair dryer turns off.

There are several possible problems here:

• Presence of breaks in the cable;
• Faulty electrical outlet;
• Lack of electricity;
• Motor failure.

Most often, when the hair dryer stops turning on or breaks down altogether, external changes occur in the operation of the device, such as the appearance of a burning smell. The reason may be that during the process of drying the hair, particles of hair got stuck in the mesh of the hair dryer and wound around the heating element. Or the situation is somewhat more complicated - the wires of the microcircuit have burned out.

Possible reduction in drying quality. The hair dryer begins to blow weakly and overheats if the filters on the back of the device are critically dirty.

If they become clogged, then the engine speed will decrease. The rotation speed of the fan blades may be reduced. The most common cause is that the hair dryer gets inside foreign body. If the hair dryer only works in the " Cold air"and does not heat up, here we can talk about such breakdowns as the blocking of the "Cool" button or burnout of the coil, damage to the microcircuit or failure of the thermostat.

Inspection procedure and how to disassemble a hair dryer

To start looking for the cause of a malfunctioning hair dryer, you just need to stock up on 2 things, the first of which is instructions for the device, and the second is a sacral impeller and a flat-head screwdriver. When starting work, you need to remember that the device must be disconnected from the power supply.

The procedure for disassembling a hair dryer (such as Remington d3700 or Maestro) includes:

1. Disassembly of the case. To do this, carefully unscrew and remove all the bolts and fasteners from the back of the device.
2. Removing the cover from the top of the case that masks the fan blades. As a rule, it is fastened by pressing or using clamps. In this case, you need to carefully lift the part with a knife or the end of a flat-head screwdriver.
3. Sequential removal of switches and regulators with wires connected to the microcircuit.
4. Inspect the hair dryer to ensure that all fastening elements have been removed.
5. Removing the heating element from the front of the appliance. The heating element must be removed extremely carefully to avoid breaking it or damaging the coil.

Next comes the inspection of the electric motor for faults. If there is a breakdown in the motor, it will be noticeable by the color and appearance contacts. In this case, extraction is not required. If the engine burns out completely, then we are talking about overhauling the hair dryer and replacing the motor.

Step-by-step instructions and repair diagram for a hair dryer

Getting started with repairs household hair dryer, should be considered design features a specific model and the specifics of the operation of all its elements. The standard procedure for repairing such a device (suitable for all Bosch models, Braun, as well as Vitek, Bebilis and Brilliantcare with ionizer) is to follow the steps.

First of all, it is necessary to clean the fan blades and the surface of the motor from the accumulated hairball:

• Remove the top cover from the back;
• Cut the hairs;
• We remove them with tweezers or using a brush.

It is important to remember that wet processing of hair dryer parts is inadmissible, since after this the contacts will stop working. Next, carefully clean the spiral and filters in case of overheating and a burning smell. To troubleshoot a hair dryer connection (or if it turns off), inspect the cord for broken wires, especially at the base of the device.

For these purposes, special testers or indicator screwdrivers by connecting to the network.

In this case, repairs are not recommended; it is better to replace the cord with a new one. Since there is a high probability of moisture getting into the insulation area and shorting the device. If no damage is detected, you need to open and inspect the heating element and its contacts. In the case when the latter have moved away from the circuit, you need to use a soldering iron. We also pay attention to how the position switch began to work. If carbon deposits are found on it, remove it with emery. If the contacts come loose (when the hair dryer does not turn on), we solder them. If the elements cannot be repaired, we replace them with new ones.

Philips: how to disassemble a hair dryer

The specificity of the device is such that in some models (for example, Brown or Bosch) there is a function for selecting air flow speed and heating intensity, while others have only separate regulators for the speed of rotation or degree of heating (in inexpensive models Vitek or Scarlett). The number of plastic blades is also different - there can be 2-3 of them and (as in industrial hair dryers) even 4. The heater consists of such parts as a spiral of wire with nichrome and a heat-resistant base under it. The hair dryer begins to heat up precisely due to the coil. The number of windings in the spiral affects the number of switch modes.

The visual disassembly diagram for such hair dryers looks like this:

1. Disconnecting parts of the housing with preliminary removal of the fastening ring.
2. Removing the covers by releasing the latches from inside housings.
3. Unscrewing 8 fasteners - 2 on the handle of the hair dryer, 3 on the side of the removable head, and 3 on the top of the casing.

Thermal protection is presented in the form of an adjustable regulator and thermostat. The operating principle of the latter is that when the permissible temperature threshold is exceeded, the terminals of such an element begin to diverge and the circuit opens. When the hair dryer cools down, the terminals are connected again, and you can dry your hair again. Another barrier in the path of hot air is a special fuse. If it is triggered, such an element will need to be changed. Also on external panel Many hair dryers have a button that allows the device to blow cold air. This function not only allows you to maintain healthy hair, but also stops the heating process of the coil.

As a rule, for a household hair dryer to operate, a constant electric current of 12-32 - 220V is required.

There are mode switches and regulators. Depending on the manufacturer, the number of speeds and availability additional options varies. The electrical circuit allows you to establish the relationship between all elements of the device.

Rowenta: how to disassemble a hair dryer

Why is the fan and its blades inspected first - since it continues to work poorly after cleaning the hair, and involves searching for cracked parts in order to replace them. Also inside the shaft there can be all kinds of small parts, attracted by a hairdryer during careless handling of the device.

Repairing the heating element includes repairing breaks in the coil by twisting the wire, using a soldering iron, or by tinning.

If the engine breaks down, intense crackling sounds will be heard from the hair dryer and even sparks will fly out in the area of ​​the blades. Then you need to desolder the windings from the microcircuit and reconnect them using triplets. But, in this case, it is best to go to a workshop, it is not that expensive (for example, disassembling Philips hair dryers in Moscow will cost only 4 USD). If everything is in order with the windings, pay attention to the brushes and whether they fit tightly enough to each other. In addition, it is best to lubricate the running parts and check their condition by manual rotation.

The following review presents the disassembly process of Rowent hair dryers (including the Beauty and YFA 223J models) and includes:

• Removing the cover from the handle using a flat-head screwdriver.
• Removing the switch from the panel.
• Removing the back cover from the case until the fan blades are located.
• Removing the volute and motor from the front part.

If the chip cracks, you need to clean it and solder it. The next step is to inspect the capacitors and replace them with new ones if they are swollen. If the resistor parts have darkened, this condition indicates that the elements have burned out. It is also necessary to replace defective spare parts.

DIY hair dryer repair (video)

If you need to independently repair a professional (such as Coifin classic or in the form of tongs, as well as electric hair dryers marked Pro) or a construction hair dryer (for example, Interskol Ef 2000), you can easily use the proposed scheme, since such devices have a device similar to household ones fenam.

Once you see a professional construction hair dryer in action and appreciate its capabilities, you also want to have such a thing at home. Remove it so carefully old paint, no harm to decorative wood and thin metal parts how to do it with a hair dryer, you will never succeed with blowtorch or a gas burner.

When working with open fire it is impossible to ensure the same safety decorative elements and work safety.

A construction hair dryer (also known as a hot air gun and a heat gun) is not at all like household appliance for styling and drying hair, which is necessary for every woman. The temperature of the blown air from a hot air gun reaches 650 °C. And there are even more powerful ones professional models, which increase the air temperature to 800 °C. Also, hair dryers not intended for drying hair have increased blowing speed to 650 liters per minute. The power of factory-assembled hot air guns ranges from 500 to 2500 watts.

The growing demand for hot air guns is fueling rising prices for them, especially for budget models. But you can assemble a construction hairdryer yourself.

Why do you need a hair dryer?

• Peeling off old paint.
• Removing stickers.
• Dismantling linoleum, vinyl coverings, tiles.
• Softening and melting of wax, resins, bitumen, solder. Molding candles from wax and paraffin.
• Dismantling and installation of microcircuits and transistors.
• Crimping of heat shrink insulation.
• Waxing furniture, skis, surfboards.
• Bending and shaping wooden parts. Drying glue after repairing surfboards and skis.
• Drying paint, varnish, plaster, plaster, wood.
• Soldering thin-walled copper pipes.
• Antiseptic wood treatment. Cleaning and disinfection of cages for birds and animals.
• Loosening rusted or heavily tightened metal bolts, nuts, screws.
• Shrink fit of bearings and bushings.
• Defrosting frozen car locks, water pipes and taps, refrigerator freezers.
• Connecting plastic pipes and garden hoses, repairing car bumpers and other products made of plastics with a low melting point (polyvinyl chloride, polyethylene).
• Bending and forming plastics with high temperature melting (plexiglass).
• Lighting coals in a barbecue.

Power part of a powerful hair dryer

The design of all heat hair dryers is the same:

• heat-resistant heating element housing;
• a heating element;
• fan;
• switching and shutdown circuit.

First What you need to do is find a piece of ceramic tube or mica plates to secure the heating element.

Second- wind the heating element. The hot air gun circuit can have up to four separate spirals, with the help of which selection is carried out temperature regime when switching the control switch. Each heating element in this case has a different resistance. Most often, to select the temperature, two spirals with a resistance of 97 and 260 Ohms are enough.

It is better to wind hair dryer coils from soft nichrome, which is easier to find. Fechral is a rarer material on sale, and the wire made from it is more rigid.

Now all that remains is:

1. Find a wire made of a material with high resistivity.
2. Measure the resistance of the wire per meter.
3. Measure the length at which the resistance of the piece will be 97 Ohms.
4. Twist the cut piece of wire into a spiral around the hairpin.

Adjust the fan to blow hot air. In the schemes of factory-assembled construction hair dryers, a commutator motor with brushes is always installed, which can operate on both AC and AC power. direct current.

To assemble a hair dryer at home, it is easier to use a fan from a computer. But the electric motor computer cooler can only operate on DC voltage, so to connect it you definitely need a rectifier diode bridge.

All factory-assembled hot air guns are assembled according to a scheme that allows you to change the blowing speed and heating temperature.

Airflow speed decreases when the electric motor is switched with a toggle switch to supply power through a spiral with a high resistance, on which the voltage drop is higher.

Heating temperature also decreases when connecting a heating element with higher resistance, which consumes less current.

Judging by schematic diagram construction hair dryer, the fan electric motor is under no circumstances connected directly to a 220 V network, and taking into account the voltage drop across the heating elements, it operates on a voltage of 9–15 V.

For the rectifier bridge VD2–VD5, you can use separate 1N4007 or finished assembly KTs109A.

As valve VD1, you must use a high-voltage diode, for example 6A10.

Ceramic capacitors of constant capacity C1 - 3.3 µF, 50 V and C2 - 0.47 µF, 400 V are necessary to reduce the pulse current during startup and connection to the network.

As you can see, assembling a hair dryer yourself is not at all difficult.

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The hairdryer operates on 220 V, 50 Hz. Any hair dryer has two main parts - a heating element and an electric motor.

As heating element As a rule, a nichrome spiral is used; it provides warm air. Hair dryers mainly use DC electric motors with a power of up to 50 watts, there are exceptions.

Passing through the spiral, the current loses its initial strength, since the spiral has a certain resistance; it is this current that is rectified by the diode bridge and supplied to the electric motor.

Electric motors in hair dryers are designed for voltages of 12, 24 and 36 Volts; only very rare models use electric motors with a power supply of 220 Volts, in which case the voltage from the network is directly supplied to the electric motor. A propeller (propeller) is attached to the engine rotor, which removes heat from the spiral; it is thanks to this that a fairly strong directed flow of warm air is obtained at the output. The power of the hair dryer depends on the thickness of the coil used and the power of the installed electric motor.

The hair dryer that was brought was disassembled, it turned out that the problem was a broken track on the circuit board with the switches. After filling it with solder, the device worked fine.

But most often, the main reasons for inoperability are a broken spiral, a non-working motor, switch contacts melted from heat, a broken power cord or plug.

Elements in the diagram: 1 - diffuser nozzle, 2 - body, 3 - air duct, 4 - handle, 5 - cord anti-twist guard, 6 - "Cold air" mode button, 7 - air flow temperature switch, 8 - flow speed switch air, 9 - "Turbo" mode button - maximum air flow, 10 - loop for hanging the hair dryer.

The electric motor is supplied with DC voltage obtained through a diode bridge consisting of four diodes (or simply from one diode).

Let's highlight two elements of the circuit that are consumers (loads), these are the spiral and the diode bridge (we do not count the motor, because it is the load of the bridge). In the circuit, the elements are arranged in series (one after the other), which means that the voltage drop across each of them will depend on its own resistance and their sum will be equal to the network voltage in the third position of the switch.

Most hair dryers entry level have simple electrical circuit, in such hair dryers there is only one switch that turns on the fan and heating element. Heaters can be made in various modifications, but in all hair dryers they are made of nichrome twisted into a spring.

However, almost all simple modern hair dryers have 2-3 stages of power and air flow adjustment.

More advanced hair dryers have smooth controls for blowing speed and temperature of the blown air.

The recommended maximum operating time is 5 minutes. Upon completion of work, turn the temperature regulator to minimum, leave it on cold air for half a minute, and only then turn off the hair dryer. Try not to take it wet hands, otherwise moisture may get into the internal elements circuit, which can lead to a short circuit.

Construction hair dryer (technical) - hand power tool for directed supply of heated air for the purpose of non-contact (indirect) heating of the processed material. The scope of application of the tool is very wide: from simple air drying room temperature, to powerful exposure to temperatures above five hundred degrees Celsius. The demand for construction hair dryers is fueled by their low price (for entry-level models), due to the simplicity of the design and, in many ways, time-tested circuit solutions.

Interskol FE-2000 is a representative of household construction hair dryers with minimal necessary set functions: smooth temperature control, two airflow intensity modes. This set, as a rule, is quite sufficient to perform the vast majority of tasks. A specific copy of this hair dryer (the first modification, board DB3011) was purchased about three years ago and had a very considerable (but not prohibitive) daily operating load. For this reason, all the imperfections in the design of the hair dryer appeared quickly.

A few months after the start of operation, the first breakdown occurred: there is no temperature control, the outgoing air is always cold. The cause of the breakdown is overheating of the BTA16 triac, its failure due to insufficient pressure to the radiator and non-use of thermal conductive paste. The repair consisted of replacing the triac with preliminary application of KPT-8 paste. This failure did not occur again.

Hairdryer Interskol FE-2000. Suitcase included.

Nozzle. A ceramic heater with a spiral inside is visible.

At the end of the first year of operation of the hair dryer, a fracture (internal wire break) occurred in the power cable next to the body of the tool. This malfunction is often found among non-professional tools. Original power cable high quality no different, has medium-hard insulation, fourth-fifth class flexibility of copper current-carrying conductors. Installation of a new cable KG 2x1.5 (in rubber, double insulation) made it possible to forget about this type of fault.

In the second year of operation, the high-resistance winding of the heater, which serves as ballast for powering the electric motor, broke. The cause of the break is difficult to establish; it could be either a manufacturing defect (which is most likely) or spontaneous rubbing nichrome wire o hard edges of ceramics, due to many heating-cooling cycles. The winding broke and the engine stopped. As a result of stopping the engine with subsequent overheating of the main (high-temperature) winding of the heating element, the thermal fuse tripped (the high-temperature winding remained intact). The body of the hair dryer was disassembled, the heating element was disassembled, and the location of the nichrome wire break was localized. The break point turned out to be not far from one of the ends of the winding, for this reason it was decided not to connect the ends of the wire, but to wind (remove) a short section. The resistance of the ballast winding was reduced, according to approximate calculations, by 8-12%, which is not critical for the engine. By this time, extraneous noise from the engine bearings began to appear from time to time and, unfortunately, its time was clearly coming to an end. The standard thermal fuse had a nominal response temperature of 125°C, it was replaced with a new one with a higher temperature of 150°C. The small temperature margin is explained by the assumption that an additional 25°C is unlikely to allow the heating element winding to burn out (in the case emergency situation), but they will give you more time to quickly turn off the hair dryer before the thermal fuse trips (breaks). To replace the thermal fuse, you need to almost completely disassemble the heating element. About half of all the ceramic rings from which the heating element core is made cracked over time (apparently due to the poor quality of the ceramics) and, when the outer mica shell is removed, the rings disintegrate into small particles. The thermal fuse is connected to the winding of the heating element and to the power wire using miniature crimp sleeves, which must be re-crimped with high quality (without special tool) is very problematic. For comfort possible replacement thermal fuse in the future, it was installed using flat connectors (automotive terminals).

By the end of the second year of operation, the plain bearings in the engine began to “ring” loudly. Also, in a random manner, the voltage on the high-temperature spiral of the heating element began to disappear and reappear when the regulator knob was rotated. These malfunctions quickly worsened, further normal use of the hair dryer for its intended purpose was not possible: the engine hummed, its speed dropped, set desired temperature heating was almost impossible. There is an urgent need to deeply restore the performance of the hair dryer.

The body of the hair dryer has been opened (photo above). Housing mounting screws (photo below).

The insides of the Interskol FE-2000 hair dryer.
From left to right: board, motor with impeller, operating mode switch, heater.

DB3011 board.

Heating element of the hair dryer Interskol FE-2000.

Replacing the electric motor.

Finding the right engine for sale is not an easy task. Therefore, when a suitable engine was discovered, the decision was made to purchase the engine regardless of its other characteristics (RPM, voltage). As a result, it turned out that the purchased motor had a supply voltage several times lower (12 V) and approximately one and a half to two times less revolutions than the standard hair dryer motor. These problems had to be solved, but first we needed to remove the old one and install a new motor into the hair dryer body. The engine replacement process is not very complicated. The greatest difficulty is removing the plastic impeller from the motor shaft. Using improvised means, we organize a wedge-shaped stop at the bottom of the hub and, using a drill with a diameter of 2 mm, we gradually knock out the engine shaft. As the shaft comes out, the position of the stop (wedge) needs to be adjusted. Be extremely careful not to damage the plastic impeller hub! Before placing the removed impeller on the shaft of the new engine, it is necessary to secure the engine with two screws and degrease the surface of the shaft with acetone. It wouldn't hurt to clean and degrease inner surface impeller hubs with gasoline or alcohol. We place the impeller on the shaft of the new engine manually (you can lightly pound it with a miniature rubber mallet), resting the other end of the shaft (located near the brush-collector assembly) against something solid.

Motor with impeller.

Close-up of a plastic impeller.

Remove the impeller from the engine.
We use tweezers as a stop. We apply light blows to the drill, which rests against the motor shaft, with a small hammer.

No capacitors were installed on the new engine.

Measuring the original engine.

Thermal fuse (photo on the left). Connector flat type RpIm+RpIp (photo on the right).

Motor power supply.

The problem of powering an electric motor can be solved in two ways: increase the length (number of turns) of the ballast winding or supply power to the motor from some other source. The first method is complicated by the need to find the required nichrome wire and a place to place additional turns in heating element(which literally crumbles in your hands). Let's take the second path - we'll make a separate power source. A cell phone charger turned out to be very suitable in size and load current. The charger board is placed next to the standard board of the hair dryer; it is necessary to ensure proper levels of insulation (prevent unwanted touching of the boards) and fastening (fixation). But there is one catch - the output voltage. As is known, charger it is about 5 V, and we need 12. Therefore, we will increase the number of turns in the secondary winding of the output transformer of the power supply (charger). We desolder the transformer, disassemble the magnetic circuit, carefully separating the ferrite core into two halves (warming the transformer to 100°C and using acetone can simplify the task). IN as a last resort, if it is not possible to disassemble the magnetic circuit, you can wind it using the shuttle principle so that the number of turns is small. The main thing is not to split the ferrite!

We find the finishing end of the secondary winding and begin to slowly wind up turn after turn, counting their number and remembering the direction of winding the wire. When the secondary winding is wound, it is necessary to make basic calculations to determine the number of turns for the motor supply voltage (in our case - 12 V): we find the number of turns per 1 V (knowing the former output voltage of the charger), multiply the target supply voltage by it . It wouldn’t hurt to add a couple of turns in reserve (if necessary, they can be quickly wound up).

We increased the output voltage by 2.4 times, the maximum load current naturally decreases by the same value. As is known, the current of a transformer winding depends on the cross-sectional area of ​​the conductor. To determine the minimum permissible cross-section of the wire for the new secondary winding, we measure the diameter (and calculate the cross-sectional area) of the wound wire, divide the resulting value by 2 (a rough approximation, we will not delve into the jungle of calculations). If the width of the gap for laying the wire allows, then it is not at all necessary to choose a thinner wire, the main thing is to fit the required number of turns and fit the magnetic circuit loosely. We wind the wire turn to turn, observing the direction of winding and counting the number of turns. Upon completion, solder the ends of the wire to the terminals of the transformer, not forgetting to remove the insulating enamel at the soldering points. We cover the mating ends of each of the two halves of the magnetic circuit with tsapon varnish, assemble the transformer by pressing the ferrite halves together until the varnish dries. We tightly wrap two or three layers of a thin strip of insulating tape or paper tape on top of the magnetic circuit, cover it with tsaponlak on top, and dry it. We solder the transformer into the power supply board, connect the motor, and measure the voltage. If it is too large, wind up the turns. When the voltage is correct, we fix the secondary winding - apply it to it thin layer tsaponlaka. The transformer is ready. It should be noted that as a result of this alteration, we received only one engine rotation speed, namely a certain average value in relation to the two original (nameplate) speeds.

Cell phone charger board before conversion.

Let's disassemble the transformer.
Secondary winding The transformer had 12 turns of wire D=0.35 mm in one layer.

Photo on the left: a coil with PETV enamel wire D=0.32 mm, which will be used to wind the transformer.
Photo on the right: wound transformer coil (29 turns of PETV D=0.32 mm in two layers).

Circular winding insulating tape(photo on the right).

The rewound transformer is installed on the power supply board (photo on the left).
The motor power supply board is ready for installation in the hair dryer (photo on the right).

The standard motor power diodes (D1-D5) were removed to obtain additional free space (photo on the left).
The motor power supply board is in place (photo on the right).

Replacing the variable resistor.

To verify that it is faulty, instead of the high-temperature winding of the heater, we connect an incandescent lamp (see a similar example in the article -). We supply power to the board and see that the lamp does not respond adequately to the rotation of the variable resistor. We unsolder the standard variable resistor, temporarily connect any other (known good) one with the same resistance of 100 K. We see correct work diagrams: the duty cycle of the lamp flashes is clearly tied to the angle of rotation of the handle (switch) of the variable resistor, and in one extreme position of the slider there is no glow of the lamp, in the other there is full heat. The malfunction has been localized, we replace the variable resistor with a new (good) one. In our case, an engine with lower revolutions was installed, and the intensity of the spiral blowing decreased. It is necessary to limit the maximum heating temperature of the coil to avoid overheating and/or tripping of the thermal fuse. To do this, in series with a variable resistor (into the gap of the side terminal corresponding to maximum power) we solder in a constant resistor, the resistance of which is determined experimentally, visually observing the color of the filament of the spiral.

The left photo shows the old (left) and new (right) variable resistors.
The right photo shows the new dual type variable resistor (2 x 100 K). Opening the case is the most quick way determine the pin assignments.

Give the required form needle files will help the resistor handle (photo on the left).
The new variable resistor is installed (photo on the right). Inside the red heat shrink tube there is an additional resistor with a resistance of 130 K.

The degree of heating of the spiral in the position of the regulator knob, corresponding to the maximum air temperature.

Measuring minimum and maximum temperature air.

Conclusions.

The technical solutions used in the design of the Interskol FE-2000 construction hair dryer of the first modification are not unique and are not highly reliable. The hair dryer is rightly not positioned by the manufacturer as a tool for professional use. The tool is quite suitable for home use. If the user has some initial level of training, it will not be difficult to restore the hair dryer’s functionality on your own, since its maintainability is good. Future owners of the FE-2000 model, and those who plan to use the hair dryer intensively, can be recommended to check the quality immediately after purchase thermal contact triac with a radiator and, if necessary, apply heat-conducting paste. It would also be a good idea to immediately replace the power cord with a better one.