A broken fan should not be thrown away immediately; the most reasonable thing to do would be to figure out the reasons and, if possible, repair the device. Often fan malfunctions are not related to breakdowns, but simply require simple cleaning and lubrication.
Some types of mechanical damage can be eliminated yourself by replacing the failed part. It is more difficult to repair floor or tabletop models with more complex design. Since fans are among the majority modern devices refrigeration and air conditioning, then each case is individual. We will consider only the most common reasons breakdowns and ways to eliminate them.
Breakdowns of household floor fans
The approach to repairing floor or table fans should be rational. The presence of speed, tilt and rotation control units for the fan significantly complicate the design. The main task is to identify the cause. If the problem is simple, then you can try to repair it yourself.
The fan is noisy, but the blades do not rotate
The most common breakdown of floor fans is when the device makes noise, but the blades remain motionless.
The reasons may be as follows.
- The bearing grease has dried out or thickened. It's easy to identify the cause. The engine is disassembled and the presence and condition of the lubricant is checked.
- The mounting of the bearings on the shaft has shifted. This occurs due to the depletion of the life of the bushings, which are made of bronze or brass.
- Motor malfunction. To check, it is necessary to disassemble the engine and check the resistance on the windings of the housing and armature.
- Loss of capacitance due to capacitor failure. It is necessary to check the capacitance of the capacitor with a tester.
If the reason is in the lubricant, you need to remove the remaining thickened lubricant by cleaning the parts with gasoline, and pour fresh engine oil into the bushings. Care should be taken to ensure that no oil gets on the motor windings.
Fan motor
If the bushings wear out, you need to look for new ones in the store or take them from another non-working device. It will not be possible to restore worn-out ones.
If the motor winding is damaged, you will have to rewind it in a workshop or buy a new motor. It is difficult to restore the winding on your own.
If the capacitor malfunctions, you must replace it with a new one from the store. If this is not possible, then it is easier to purchase a new fan.
The fan makes a whistling sound
Whistling sounds may appear several months after purchase. Fan buzzing or creaks due to deformation of the propeller or loosening of the plain bearing fasteners. Exposing the blades to direct sunlight or high temperature leads to bending and imbalance during rotation. Similar sounds are also caused by indentation as a result of mechanical damage to the protective grille, to the surface of which the tips of the blades begin to reach.
Bearing failure
If extraneous noise occurs, do the following:
- disconnect the device from the power supply;
- remove the protective grille and inspect it for deformations;
- remove the propeller, inspect the blades for possible bends;
- inspect the bearing fasteners, check that the bolts are tightened.
The bending of the protective grille can be easily corrected by carefully straightening it with your hands to the desired state.
Note! If the geometry of the blades is damaged, the propeller will most likely have to be replaced, since polyurethane cannot be returned to its original shape at home.
If the cause of extraneous sounds is loosening of the fasteners, then you just need to tighten all the bolts until the backlash is eliminated.
The device does not turn on
If the fan does not respond to pressing the power button, it may indicate a broken wire in the cable, a damaged connection between the cable and the terminals in the socket, or a malfunction of the socket itself. The button block or the speed shift buttons themselves may also be damaged.
First of all, you need to check whether the control light comes on when you try to turn on the device.
If the light does not light, you need to do the following:
- measure the voltage in the outlet by connecting a working device to it;
- unscrew the plug and check for damage where the wires are connected to the terminals;
- disconnect the cable and check it with a tester for current flow.
If there is a malfunction in the plug, you need to restore the connection of the wires, possibly soldering the terminals. If a violation occurs in the wires inside the cable, it should be replaced with a new one.
Checking contacts with a tester
If the light comes on, but the fan itself does not work, the following steps should be taken:
- make sure that the device is disconnected from the network;
- disassemble the control panel, which is located on the fan housing;
- Use a tester to check all key contacts for current conductivity;
- check the speed controller with a tester.
If you discover that one of the buttons is broken, you should either purchase a working replacement from a radio store, or make a direct connection, bypassing it. If the speed controller fails, it must be resoldered or also replaced with a new one.
Fan does not turn
The reason why the fan does not turn left and right is that the crank is not working correctly.
To fix the problem you need to do the following:
- remove the back cover by unscrewing the fixing bolts;
- check the connection of the crank with gear wheel under the gearbox;
- put the crank in place, or replace it if it is broken.
A situation may also arise when turns are not completed completely. In this case, it is necessary to check the travel of the gear switch according to vertical axis. If there is any malfunction in its operation, it is necessary to disconnect the fixing bolt and lubricate the shaft, gear and top part gearbox If the plastic gear is worn out and you cannot find the part on sale, you will have to accept the fact that the fan does not rotate.
Good gear
When installing the impeller after eliminating the malfunction, you must follow the balancing rules, otherwise the fan will not rotate normally. The simplest and in a convenient way is static balancing.
Install the fan manually, set the initial rotation by hand and mark the top point of the impeller with a pencil or marker. They make several more runs and check whether the obtained points of advantage coincide with the initial mark. If they do not match, then there is a fault in the bearings that need to be lubricated or replaced. If they match, take objects with different weights, such as nuts, pieces of electrodes, etc. For fastening, electrical tape, adhesive tape, mastic, plasticine, and thin wire are used.
Then they begin to attach them as a counterweight to the point of advantage in order to achieve its loss permanent place. For more precise selection You can grind off weights using a hacksaw. After finding the optimal weight, the weight is welded or glued to the non-working side of the disk.
Balancing with screws allows you to quickly determine the required settings experimentally. But this option is not available on all fans.
You can also carry out balancing on balancing trestles by contacting specialists.
Possible breakdowns of Timberk fans
Timberk fans have proven themselves as inexpensive and easy-to-use devices for creating comfortable climatic conditions, maintaining air exchange in an apartment or office. Despite their good quality, they are prone to breakdowns.
Fan Timberk
During operation, customers noticed the following malfunctions:
- drop in airflow due to soft plastic blades;
- There are times when a capacitor fails;
- the appearance of extraneous noise during operation;
- electric motor failure;
- the rotor breaks;
- strong backlash appears;
- at long work there is a smell of burnt oil;
- the legs bend and change geometry under the weight of the motor;
- overheating of the power supply;
- mechanical failures at fastening points.
In terms of price-quality ratio, Timberk products are leaders in their segment. All devices have a manufacturer's warranty and can be replaced when contacting service.
Fan malfunctions in car cooling systems
The fan is turned on by a sensor located in the cooling system. Reacting to the signal, the cooler turns on and directs additional air flow to reduce the temperature of the fluid and engine. A number of failures are associated not with breakdowns of the fan itself, but with the operation electronic sensors responsive to changes in the system.
Fan relay clicks frequently
The fan relay often clicks in automotive cooling systems. The reason may be either oxidation of the relay contacts or temperature surges that cause it to operate. The following are subject to diagnosis:
- sensor;
- wiring;
- the controller has a circuit to control the fan.
A breakdown can cause engine damage, since incorrect operation of the sensors causes incorrect ignition timing.
Cooling fan
First of all, you need to go for diagnostics and ring the nodes with a scanner. If a damaged segment is detected, it must be replaced by installing a new one.
Cooling fan turns on frequently
The cooling fan turns on frequently. It is considered normal when the periods of fan inactivity exceed the duration of its operation. If this algorithm is violated, the reasons may be the following:
- clogging of the cooling system;
- decreased coolant level in the radiator;
- The thermostat is faulty;
- the pump does not work;
- presence of air pockets.
Cooling system clogged
It is necessary to flush the thermostat and radiator, add coolant, check the functionality of the water pump and replace it if necessary. Air plugs in the radiator are expelled by applying pressure of compressed gas. If the sensor malfunctions, if its switching temperature does not coincide with the passport values, the device must be replaced.
Air conditioner fan not working
The reasons why it does not work may be the following:
- the clutch on the main fan is faulty;
- switch relay contacts have oxidized;
- fuses are blown;
- the power supply terminals have oxidized;
- insufficient refrigerant levels;
- The armature brushes have oxidized.
Air conditioner fan repair
It’s better to call an electrician for service so that he can examine the condition of the air conditioner with a multimeter and find out the cause of the breakdown.
Reducing fan start temperature
In the hot season, the factory settings of the fan relay do not allow full operation of the car. In traffic jams, the engine may begin to boil, which can lead to more serious damage.
Flashing the ECU
In order to reduce the temperature at which the fan turns on, you can use the following methods:
- reflash the ECU settings when visiting the service;
- pour antifreeze with a higher boiling point, for example, 120 degrees;
- check the pressure level and the tightness of the tank cap;
- install a trip computer with the ability to adjust the fan temperature or a forced switch button.
More low temperature will allow the fan to start earlier, which will have a positive effect on engine operation.
Random fan switching on
The radiator fan must turn on when the engine temperature is high to cool it down. However, sometimes the device turns on randomly, even though the thermostat sensor shows comfortable temperature at 25-35 degrees.
Clogged air filter
The reasons for this may be the following:
- low-quality fuel, additives in which reduce the flash point in the engine;
- insufficient level of antifreeze;
- the air filter is clogged;
- climate control turned on;
- The cooler thermal switch has failed.
If you suspect low-quality fuel, you need to measure the temperature of the exhaust gases. A heavily contaminated radiator is washed plain water from a hose.
On a note! When the air conditioner is running, it is normal for the fan to constantly turn on.
You should stop by for diagnostics and check the functionality of the thermostat. If necessary, add or replace antifreeze.
Ventilation problems in apartments
Built-in exhaust fans are much easier to install constructively. But their cost is low and it is often easier to purchase a new one than to look for parts that have disappeared from circulation. Poor ventilation of rooms may not be due to the operation of the device itself, but to errors in the organization of the exhaust system.
Ventilation in the bathroom
If ventilation in the bathroom does not work, the air becomes humid and is not ventilated, laundry does not dry well, and mold may appear.
Normal ventilation pattern
The reasons may be the following:
- the ventilation hole is clogged with dust and cobwebs;
- foreign objects in the shaft;
- The exhaust fan is set to draw in air instead of exhausting it.
The correct solution to the problem would be to contact management company. Specialists lower a load into the ventilation shaft all the way to the apartment to break through all obstacles. In particularly advanced cases, a camera is lowered into the shaft to determine the location of obstacles. The ventilation shaft is opened from the entrance. You may have to go around your neighbors in the riser and check if they have the wrong installed fans, which disrupt the hood.
Advice! An exhaust fan is suitable for the bathroom, preventing air flow from the ventilation shaft.
Hood in the kitchen
Exhaust ventilation is designed to remove unpleasant odors and stale air. However, if the construction technology is violated or due to other reasons, air begins to enter the apartment from the exhaust vent, despite the working fan.
Ventilation shaft contamination
Because of this, foreign odors arise in the apartment. Cooking products are not removed from the kitchen.
The reasons may be the following:
- design defects in ventilation shafts and ducts create reverse draft;
- strong gusts of wind in one direction blow air currents into the mine;
- accumulation of vapor masses and frosty air in ventilation;
- mine contamination with snow and waste.
Eventually axial fan draws air masses from one shaft to another and the hood begins to silently work in the opposite direction.
It is better to invite specialists to resolve the shortcomings. They will evaluate the rational use of equipment in accordance with the documentation and conduct a high-quality examination of installation and operation ventilation system. The resulting report will indicate all deficiencies existing system and measures to correct them. Management company employees are required to clear the ventilation shafts of foreign objects. Also, to get rid of the reverse draft effect, install a deflector in the hood to suck in smoke and create through air flows in the kitchen.
If a household fan, both table and floor, breaks down, do not rush to immediately take it for repair, much less throw it away. Most likely, a simple problem has arisen, and you can repair the fan yourself.
Household fan It is not complicated in design, and the principle of its design can be seen in the figure below.
If you look closely at the figure, it becomes clear that the electric motor, gearbox, crank, rotation speed switch and propeller that creates the air flow can fail in the device.
The main difference between a desktop cooler and a floor cooler is the high stand floor-standing version. Otherwise the designs are identical.
So, the main malfunctions that you can observe in the cooler you purchased:
- the unit does not turn on, the power light does not light up;
- the device does not work, but the light is on;
- the cooler blades do not rotate well;
- the unit does not turn to the sides;
- The cooler makes a humming noise and does not rotate.
The unit does not turn on
In this situation, there may be 2 options: the light indicating that the unit is ready for operation may light up or not. Depending on this, the breakdown diagnostic algorithm will differ.
The light doesn't light up
If, after plugging the device into the outlet, the light located on its body does not light up and it does not start, then, first of all, you need to check whether there is socket voltage. This is done simply: take any electrical appliance and plug it into this outlet. If the device works, then you need to look for a fault in electrical plug and cord.
To check the plug, unscrew it and check that the wires are securely connected to the terminals. To check the cable, you need to disconnect it from the terminal block of the device and “ring” it with a tester. If a break is detected in the cable cores, it should be replaced.
The light is on
The reason for this behavior of the unit, when the indicator light is on, but the fan does not work, and no sounds are heard, may be caused by breakdown of the block with buttons. To check the buttons you will need to disassemble the button block located on the stand floor fan or a stand on a desktop device. But, before disassembling the device, make sure that it is unplugged from the outlet.
The operation of the buttons is very simple: there is an “on” and “off” position. It is necessary to check the “output” and “input” on each key using a tester.
If a faulty button is detected, it cannot be repaired. Therefore, the switch should be replaced or the connection made directly. This approach to solving the problem will help to put the unit into operation if you are far from the store, for example, in the country.
Faulty speed switches may also be the reason why the fan does not turn on. To check the regulator, you will need to put it in the maximum position and check the “input” and “output” using the same tester.
Cooler blades do not rotate well
If the fan does not pull and does not move air well, you will need to disassemble the housing in which the motor is located. Sometimes the fact that the propeller does not spin may indicate insufficient lubrication in the plain bearing installed in the electric motor.
The fan is disassembled as follows.
The fan does not turn to the sides
How to fix a floor fan if it stops spinning (turning) from side to side? It's all about crank, the mounting screws of which may become loose or unscrewed. To find out, you will need to disassemble the motor housing. If during operation of the unit the body turns with a delay or a complete stop, then you should check gears in the gearbox for snagging. It is also necessary to check the gear switch itself, namely, its movement up and down.
Disassemble the gearbox and remove the main gear. The shaft will also have to be pulled out. Apply lubricant to all moving parts and assemble the gearbox. If the gears are heavily worn, they require replacement, although it is quite difficult to find analogues of broken fan parts. In this case, you will have to assemble the unit without a gearbox and use the cooler in normal mode, when the air masses move in one direction.
The cooler makes a humming noise and does not spin
Cases when the fan does not spin and the motor hums are quite common. There may be several reasons causing this failure:
- lack of lubrication on the bearings (what to do was discussed above);
- capacitor failure;
- electric motor malfunction.
Capacitor failure
Repair of a floor fan in this case comes down to checking capacitor capacity using a tester. To get to the radio component, you will need to disassemble the motor housing. Detailed description How to disassemble the case was given above. After removing the casing, you will see the capacitor attached to the motor.
The presented device has a capacitor capacity of 0.85 microfarads. For this reason, the device must be set to a value ranging from 2 microfarads to 200 nanofarads, as shown in the figure below.
In this case, after connecting the capacitor to the device, it is clear that its capacity is 0.841 microfarads. If we take into account the error of ± 5%, then the capacity of the radio component is within normal limits, and it is not the reason why the cooler stopped working.
Engine malfunction
When repairing a fan with your own hands, you also need to “ring” the electric motor in search of a breakdown. If it is faulty, the device will not turn on and will make a humming noise. It is necessary to measure the resistance at two stator windings, having first disconnected the wires going to them, as shown in the following figure.
As you can see, the resistance is also within normal limits, since its value is 1215 Ohms (1.2 kOhms). Otherwise, the device will buzz but will not turn on. In such a situation, the motor will need to be rewinded in a special workshop.
The device is very noisy
Since the propeller of the unit, the main task of which is to create air flow, is made of plastic (not always of high quality), there is a high probability of deformation of the latter. This usually happens if the unit is left on for a long time under straight lines sun rays, or near a source of high temperature. When deformed, the balance between the blades is disturbed, which causes strong vibration and noise during normal air flow.
Shaft vibration may also occur due to a sliding bearing sleeve that has become loose from long-term use.
Often when a device falls, when the blades are spinning, the protective grille is deformed. If a rotating propeller hits it, one of the blades may break.
To summarize, we can say that in different fan models, the main components and control elements may look different. But this does not change the principles of diagnostics and troubleshooting.
The most reliable fans of 2018
Table fan Mystery MSF-2428
Floor fan Stadler Form Q Fan Q‐011/Q-012/Q-014
Floor fan Electrolux EFF-1000i
Floor fan Stadler Form Charly Fan Stand C‐015
Floor fan Polaris PSF 40T
On the hottest summer days, the only salvation from the sweltering heat is a regular floor fan.
Not everyone can afford a full-fledged split system or even a mobile air conditioner. 
But unfortunately, even this inexpensive and accessible wind blower breaks down from time to time. Chinese models especially fly like seeds.
And there is an overwhelming majority of them in our market. What to do if the fan stops rotating and working? What are its main problems and why does it break down?
Let's take a closer look.
Why doesn't the fan work?
In total, there are 5 main reasons for the failure of floor fans: 
- old dried grease or lack of it
- dried out capacitor
- blown thermal relay or fuse
- turn short circuit of windings or wire breakage
- mechanical displacement of the motor shaft
The main problem of cheap models, which for some reason few people pay attention to, is incorrect casting of the blades. Because of this, an imbalance occurs, bearings break, and gaps increase. 
You cannot influence this in any way, since you already bought a fan with such an initial defect. Sometimes it seems to work, the impeller rotates normally, but it does not blow.
That is, there is no cooling air flow from it. Why is this happening?
Due to the incorrect angle of attack of the blades. Its petals are deformed and racing air flow in a circle, rather than being thrown out. 
This effect can appear over time, after the fan has been standing in direct sunlight for a long time and its impeller, having heated up, begins to gradually change its shape.
This can only be treated by replacing the impeller with a new one.
Floor fan does not spin
The most common problem is dried out lubricant or lack of it. The fan begins to jam, lose speed and, as a result, the load on the engine increases. The wind blower no longer operates at full capacity. 
The motor, wound with a thin wire of 0.2 mm, begins to heat up and the windings gradually burn out.
How is such a defect detected? In this case, the fan stops rotating. It hums, but the impeller does not spin. 
It also happens that it starts only at 3rd speed, and does not respond at all to the first two. It just doesn't have enough power to turn the shaft.
In order to start it, you have to brazenly spin the blades like on old airplanes. 
By the way, the same symptom can occur if the starting capacitor is damaged. Without instruments, how can you find out which reason is to blame for the breakdown?
To do this, you need to at least get to the engine shaft by removing the protective casing and blades. If the shaft rotates by hand with great difficulty, blame dirt and dried grease. 
And if it spins easily and has inertia, then most likely the air conditioner is covered. Symptom - plugged in the fan, but it does not spin. At the same time, you crank the engine up and it starts.
If you hold the fan blades with your hand while working, it may stop again. The capacitor is checked with a multimeter if it has an appropriate capacitance measurement scale.
To replace, select a new condenser according to the same parameters as indicated on the body of the old one.
By the way, a capacitor that is not yet completely dry also affects the speed. If you notice that they have fallen and the fan has begun to spin more slowly, this is a sign to check it.
The problem of tight rotation is solved by new lubrication of the bearings. So-called plain bearings are used here. Some people call them bushings. 
It’s a bit expensive to use balls in such designs, and they rattle over time. For repairs, it is not at all necessary to disassemble the entire engine. Just unscrew a few screws and spray the right places universal aerosol WD40.
How to disassemble a fan - instructions with photos
How to get to the bushings without removing the engine? To begin, unscrew the central screw on back wall protective casing. 
Another self-tapping screw is hidden in the adjustment button-lever for turning or stopping the fan head. 
After this, the back cover can be easily removed from its place. What's underneath? Here you can see the rotation gearbox that gives rotation to the entire head.
A special rod connects to it from below. 
The starting capacitor of the engine is fixed on top. 
By the way, keep in mind that it may not be there in different models. In this case, look for it near the speed shift buttons. 
To access the motor bearing, you will need to remove the gearbox. It is secured with three screws and supported from below by a rod. 
Tighten the screws and disconnect the rod. After this, the gearbox is removed from the shaft and you have access to the rear bushing.
There is no need to unscrew or disassemble anything else. Vedashka will do the rest for you. 
Place a narrow guide tube on the WD40 can and poke it several times into the gap between the shaft and the bearing. 
After spraying WD40, turn the shaft in different directions by hand and move it back and forth a little. 
Excess thickened grease, foreign debris and dust will gradually come out. This excess dirt can be easily removed with cotton swabs. 
If you have a thick lubricant like cyatim or litol, it is advisable to apply it to the gear worm. After these cleaning procedures, drip onto the bearing with outside a few drops of sewing machine oil. 
Just don't apply it too much. Otherwise, it will eventually spread all over and dust will stick to it, turning back into dirt. As a result, you will again get a wedge and a problem with fan rotation.
In some models, felt washers are placed near the bushings. They are saturated with oil and when heated, the oil flows onto the shaft, lubricating it. 
Everything is assembled in reverse order. Rod - three gearbox screws - outer cover.
By the way, if you overtighten the central screw on the back cover, and this is a self-tapping screw, not a screw, it can pass through the plastic of the rotary gearbox and rest against the shaft.
You will again have problems with revs and jamming. Sometimes the cause of a breakdown is trivial and unpredictable.
We've sorted out the rear bearing, then move on to the front part of the fan. There is a protective cap in the center here. 
It unscrews, attention - clockwise, since the thread here is left-handed.
You throw it off and remove the propeller from the shaft. You now have access to the front journal bearing. 
The principle is the same here. First, squeeze out and soften the old grease and dirt with a Vedashka, and then apply new one. 
After that, put the propeller back on and close the lid. Having completed the repair, turn on the fan at high speeds, let it run for a few minutes, and switch to the speed required.
Short circuit of windings or broken wires
If the damage is more complex and simple lubrication does not help, you will have to disassemble the fan in more detail.
First, you do all the disassembly machinations as indicated above. After removing the propeller, unscrew the plastic front lock nut, which is located immediately behind it, and remove the entire protective frame. 
In your hands you still have the motor itself and the leg in which the power wires pass and the push-button mechanism is located. 
You disassemble this leg by unscrewing 6 screws. 
First of all, check the soldering of the wires. It is quite possible that one of them, or even several, has fallen off or burned off.
If everything is intact, how can you tell which wire? where is he going and what is he responsible for? Start testing with two wires from the power plug.
One of them, let it be black (as in the photo below), goes directly through the backlight to the fan motor. 
The second wire goes to the lower terminal of the dial switch (button 0). 
Next, by pressing the corresponding buttons - 1st speed, 2nd, 3rd, certain switch contacts are closed, and thereby the engine speed changes. 
Each wire from these buttons goes to its own terminal on the winding, with a greater or lesser number of turns. By applying voltage to them, you make the propeller spin faster or slower.
Floor fan connection diagram
A simplified diagram of a wind blower looks like this. 
Typical circuits for most inexpensive 3-speed floor fans are something like this:
Pressing each button is accompanied by the closure of its contact group. 
At the same time, another contact Group at this moment it opens.
Sometimes these contacts burn out or do not reach their plate. Then you lose any of the speeds.
All this is checked simply with a Chinese multimeter, in circuit continuity mode. 
If your very first wire breaks or there is no contact on it, the fan motor simply will not start. Therefore, if the fan is completely inoperative, check it first.
Unless, of course, before you make sure that the plug itself and the power cord from it are working properly. This is also caused by the tester.
Place one end of the probes on the pin of the plug, and touch the other end to the contact pad on the “0” button. If working properly, there should be zero resistance. 
Then you can check the wires in the same way at all speeds. A contact probe on the plug - another probe on the outgoing wire from the corresponding speed button to the engine. 
If there are zeros everywhere, then the switch and wires are working.
Next, check the second contact on the plug and the wiring that goes directly past the switch to the engine. Make sure your cord is intact here too. 
Only after this can you proceed to checking the windings of the motor itself.
How to check fan windings
Set the resistance on the multimeter to 2000 ohms. Next, in order not to bite the wires anywhere, at the place where the capacitor is connected, strip off the insulation a little.
Search common point circuits as in the diagram below. 
Having found it, you call up the resistance of the winding. To do this, touch the contacts on the switch with the second probe one by one.
Approximate fan winding resistance values can be as follows: 
Of course different models they may differ slightly, but the most important thing is that there is no break or short circuit. Measurements can show either several hundred Ohms or a little more than 1 kOhm.
It all depends on the power of the fan and the cross-section of the wire.
The resistance between the terminals of the windings will be lower - 100-200 Ohms. 
The capacitor winding and the total resistance of all windings combined are also checked. 
Here is the most competent and complete video on checking the performance of fan windings with a multimeter.
If checking the integrity of the windings also does not reveal any deviations or defects, move on. To do this, you completely disassemble the fan, as they say, piece by piece.
Engine disassembly and malfunction
First, the engine must be freed of all plastic parts. Unscrew the 4 screws from the front side and remove the cover. 
On new models, in addition to screws, there are also latches. They need to be bent with a screwdriver. 
To disconnect the leg, you need to find another screw, which is usually hidden under the plug.
Loosen it and pull out the mounting shaft. To dismantle the wires that pass through the leg, you will need to bite them out or unsolder them from the terminal blocks on the speed buttons. 
At the same time, write down or sketch where each one is initially connected.
As a result, you should have a bare fan motor in your hands without anything unnecessary.
Let's take it apart. Unscrew the screws holding the back cover together. 
At the same time, before disassembling, be sure to put marks on all covers and hardware indicating how everything was originally assembled. 
Otherwise, after incorrect docking, you will lose alignment. There will be problems with the shaft wedging and the rotation of the blades.
Thermal safety relay malfunction
After removing the bearing, you get to the windings themselves. Among the bundle of power wires coming from the switch, look for a special thermal relay. 
Very often the engine stops working after it burns out. This relay should operate and open the circuit at a winding temperature of 135-145 degrees.
After cooling, the relay closes again and the fan starts. So, sometimes it burns out completely and actually plays the role of a fuse. 
If your fan often turns off and starts again on its own, this protection is to blame. Know that it doesn't just work. This means that your shaft is either jammed, or the windings are exhausted and they are overheating.
Overheating of the windings may be associated with the destruction of the small impeller, which is located on the shaft inside the motor itself. It is designed to blow air and reduce the temperature of the coils.
The cheapest models do not have a temperature sensor-relay; everything is connected directly. Based on this, if your “thermal fuse” has burned out, you can, of course, bypass it and start the wind blower. But at the same time you will be left without fire protection. 
This relay is also checked by the tester. 
There should be a chain between its legs in continuity mode.
Shaft displacement and broken turns
If all the parts and relays inside are intact, all that remains is to carefully examine the windings, shaft and rotor through a magnifying glass. You may see broken or damaged copper strands. 
This happens when a bearing jumps out of its seat and the rotor begins to hit the windings.
With modern Chinese floor fans, the screw connection between the two halves of the engine. Do not forget that the shaft on both sides is mounted on self-centering copper-graphite bushings, which are tightly locked in the covers.
When assembling and tightening them, you can lightly tap the transformer iron itself with a hammer so that the shaft rotates easily, with little inertia. Someone tries to catch the center on their own and creates such a quiet horror. 
Eventually the shaft falls out of the bearing, resulting in a wedge. As a result, the rotor begins to scratch the windings and its surface. 
Also keep in mind that if your fan fell and then stopped working and rotating, then the bushings are most likely misaligned here too. Nothing else can break from such a fall.
This will not damage the capacitor, and the windings covered with varnish will not break. Perhaps some buttons may move away. But first of all, check the alignment of the bearings. And then everything will work as it should. 
Unfortunately, with mechanical defect windings or rotor, as well as their intra-turn short circuits, you cannot handle on your own. It is not rational to rewind the engines of cheap wind blowers; it will be much easier to buy a new model.
However, this is already last stage check, and there is hope that you will never get to it, having found the damage somewhere else using the methods discussed above.
Let's look at the 4 main reasons why a computer fan does not work. The problem can be solved either with or without replacement of the part.
from 120 rub. RUB
Each of us may encounter such a problem as the absence of a familiar buzzing sound when turning on the PC. At the same time, the system will boot well (at least without failures), everything seems to be fine, but there is no such sound as we are used to.
If such troubles have not passed you by, then your computer fan is not working and you definitely need to do something about it!
Operating the device without a cooler is prohibited, since without cooling you may face serious troubles.
Most electronics are sensitive to overheating, and if your PC's rear fan isn't working, subsequent repairs can be more expensive. What to do in such a situation? We'll talk about this today.
Why doesn't the cooler work?
There are not many reasons why a fan on a computer may not work. This PC element is one of the simplest, but at the same time the most important in the entire system, because it is responsible for cooling sensitive electronic parts. Here are a few of the most common problems, which are most often the answer to the question: why does the cooler not work?
So, we have found out the main reasons why a fan may fail. Next, let's talk about how such malfunctions are eliminated.
The computer fan does not work: how to deal with the problem?
If your fan has failed, you should never use your computer. But what to do? At all do-it-yourself repair It is not recommended, since the device can still be broken, which can lead to a variety of consequences.
Experts from Expert will help you solve any problems with the cooler, regardless of your PC model.
There are usually two solutions to the problem:
- Option one: no replacement. The fan may be in good working order, but it may also develop lubricant, which can significantly deteriorate the quality of its operation, even to the point of failure. In such cases, the fan is dismantled and complete disassembly, applying new lubricant, re-installing the connection and testing the operation.
- Option two: replacing the part. Repairing fans is usually impossible. Yes, and inappropriate. The cost of components is cheap, but there can be a lot of work. As part of this work, we completely dismantle the old cooler, install a new one (you can buy it yourself, or the technician will bring it with you), connect and check the functionality of the replaced part.
When turned on, your little assistant begins to hum and emit unpleasant aroma? Another one frequent breakdown The fan consists of blades that do not spin. Why is this happening, because just yesterday the device was working properly. Unfortunately, many users encounter this problem, especially when actively using the device. Today we will figure out why the fan hums but does not spin?
Let's sort it out together
If the floor fan does not turn on and visual inspection did not give results, you will have to unwind the device. To do this, prepare a screwdriver and pliers in advance. By the way, this method is suitable for those who are concerned about why the floor fan spins up slowly. Reanimation of the device is carried out in several steps:
1. Remove the grille that covers the fan blades. As a rule, the mesh is secured with three latches.
2. Next, remove the impeller. It is secured with a plastic nut. It needs to be unscrewed. Proceed carefully so as not to damage the parts. Otherwise, you will have to come up with an alternative to the nut. By the way, also carefully remove the impeller. In inexpensive fans, plastic elements quickly fail under the influence of heat and air. As a result, the impeller may crumble right in your hands.
3. Now you need to disassemble the case. First, remove the nut that secures the rear grille. Then gradually remove the screws, first from the front and then from the back of the fan.
4. Once you reach the device casing, you can remove it. In front of you will be an engine and a gearbox. The last part is made of plastic. A capacitor is attached to it. It is necessary to start the engine.
5. The next step is to remove the gearbox. It is attached with several screws. After unscrewing them, you can easily remove the gearbox with all the filling.
6. Next, remove the screws that connect the motor housing to the stator. Now we can remove the front and back of the box. You will come across rubber bands as you go, put them in a separate container. You can also place small screws there.
7. Now we begin to clean the bearing itself and the surface around it. We remove dirt using ordinary cloth. Then you should degrease the surface, acetone will do, and wipe everything dry. You need to drip some oil from the oil can into the center of the bearing.
This way you remove the thick grease that gets inside the engine. As a result, it jams and the fan blades stop spinning. The described process can be repeated for a tabletop device, since they are designed in the same way.