Thermopot no water supply. We carry out repairs if the thermopot does not heat

Objectively arguing, seeing the minimum price limit for the device of 1,300 rubles (Eldorado), repairing a thermo-pot with your own hands is a thankless task. Products rarely break, new ones are provided with a guarantee (store, manufacturer). For those who want to repair a thermo-pot with their own hands, for those who are hunters, who make a living by fixing, suppliers will provide spare parts separately for various modifications of the device.

The metal body protecting the thermo-sweat should not be heated by water. A serviceable product is equipped with a pump controlled by a mechanical button (trivial pump), or an electric one. The thermo-pot modes function properly for any duration of operation. The listed signs characterize a properly working modern analogue of a samovar. Deviations indicate a breakdown of the thermopot. Even a sticky button.

The Vitek thermopot power supply board costs over 800 rubles. Textolite carries:

• transformer;
• diode bridge;
• several resistors, capacitors.

A typical getinax substrate is supplemented with a pair of active elements, mainly transistor switches. A new VT-1187 thermopot costs 2,000 rubles, control and power boards - 1,500 rubles (a difference of 25%). A $ 30 pump will shake the will of a seasoned repairman as strong as a rock - an economically unprofitable event. Do you still have a strong desire to repair a thermopot yourself? Let's start by examining the power cord.

Network wire

The body of the thermal pot is fastened with several screws: unscrew the fasteners, after pulling the plug out of the socket A block will be found inside, we begin with a visual inspection. Burned parts inside the thermopot accurately indicate the breakdown location. The cord is neatly separated, the tester rings out (diode mode). The detected wire malfunction will not delay the repair of the thermopot.

Microcircuits

A typical thermal pot holds two printed circuit boards:

1. Nourishing.
2. Manager.

Both the master will inspect, revealing the presence of swollen capacitors, burnt resistors, unusable fuses, broken tracks. Defective radioelements are replaced with new ones, soldering, contacts are restored by tinning.

The first study concerns the presence of fuses, the integrity of the elements. If the replacement fails, the new element burns out - the cause of the problem is the electronic filling. The thermo-pot is damaged by a short circuit (a sharp uncontrolled increase in current).

The resistor values \u200b\u200bare indicated by colored stripes. A common problem is to detect the beginning and end of the marking.

Hint: there are special sites containing tables of all kinds of resistance designations. Get access to the resource by filling out the search engine line with the simple phrase "marking resistors online." The direction of the stripes is determined by the observed fact: a fixed set of colors meet from one edge.

Defective electrolytic capacitors are easier to notice - the cylinders swell. Newbies looking for ways to fix a thermopot are interested in the appearance of a broken container. The answer will come automatically, only a faulty capacitor comes across. The appearance of the cylinder prompts the thought: the keg is 100% swollen. The sidewall especially protrudes (imported ones are cut crosswise).

It is more difficult to test with diodes, but the semiconductor burns less often (silicon keeps temperatures below 150 degrees Celsius). Solder the element, ring both sides. The arrow markings show the direction of flow of positive charges (lean against the positive lead of the tester).

The torn tracks of the board must be cleaned with sandpaper, peeling off the varnish on the metal. The shiny surface is tinned (soldering irons), butted, covered with solder. It will serve for decades. Mechatronics masters repair and work ...

water pump

The thermo-pot pump serves the purpose of supplying water through the tap. Manual, electric modes are possible. The construction, formed by several simple windings, will not present mysteries to an experienced electrical engineer. In pairs, contacts are called, otherwise, for the mentioned Vitek 1187, you will have to pay $ 30, looking for a new pump. It will be useful to check the pump removed from the thermo-pot for suitability by setting the required voltages to the control windings. Remove the required 12V from the batteries, car battery.

The desired voltage is given computer units nutrition.

Heating elements and thermal switches

Flat metal sheets equipped with terminals are not recommended to try to replace with homemade ones. The cost of heating elements on the shelves starts at $ 45.

Overheating protection is provided by bimetallic thermal switches. The characteristics of the thermo-pot are determined by the control part. Usually there are several thermal switches, one controls the water parameters, the second protects against the inclusion of an empty tank. In the latter case, the heating element acquires a temperature above 100 ºС, opens the power circuit.

The surfaces of the tank, the thermoswitch flange are in contact. To improve the contact, a special paste is used, similar to the covering pad of a processor cooler of a personal computer.

The principle of the sensitive element is as simple as possible. Having noted the fact that the controlled environment has reached a certain temperature, the contacts of the thermal switch open. The parameter value decreases (15 - 30 ºС) - conductivity is restored. It is difficult to find the type of components; having read the description of the thermal pot once, the body of the part is marked accordingly. The latter will allow you to choose a suitable spare part.

More often, the manufacturer is not content with the given protection scheme, supplementing the equipment with thermal fuses: small cylindrical parts tightly pressed against the tank wall with strips (brackets) glued. Having fixed the achievement of the critical temperature by the metal container of the thermopot, the fuse blows out, further work is impossible without replacement. Therefore, it is necessary to carefully inspect the product for such damage.

The serviceability of the bimetallic contact (room temperature) is checked by continuity. Desolder the part before the procedure. Normal conditions leave the contacts short-circuited.

Typical problems

Most thermopots operate a hackneyed electrical circuit, making it possible to isolate typical symptoms of a malfunction for units:

1. The device does not turn on, there are no signs of life. The serviceability of the power cord, fuses, thermal switches is checked.
2. The water does not boil when pouring, the reboil button is operational. The thermoswitch of the bottom is broken.
3. Reverse situation: the reboil button does not work. The elements of the electronic filling are to blame. You must trace the circuit from the power supply to the circuit ground.
4. There is no main heating, the order with the auxiliary. A heating element has burned out, or the power supply circuit is broken.
5. The water supply is lousy. Two options:

• An additional heating element has burned out, the situation is diagnosed by the absence of standby heating.
• The pump motor is defective.

What are thermopots

To top it off, we want to familiarize the reader with the types of thermopots. Let's discuss the models that the search engine stubbornly hides, ignoring the obvious attractiveness of the product. The costs of SEO promotion unfairly distribute the results.

Ceramic thermo pots in appearance (and material) differ little from a teapot made of baked clay. VC-3230 with a volume of 1.2 liters, traditional three temperature settings, a convenient stand that can accommodate a control panel. Why does the manufacturer use the services of potters when making a thermopot body? Environmental friendliness. A popular word today. Humanity knows no more harmless materials than shards of baked clay used for thousands of years.

Thermopots are designed for small gatherings. Water boils for a few seconds. A minute is enough, get 1 liter of boiling water. The option is ideal for housewives who have sat down to forget household chores.

The Japanese manufacturer Zojirushi will help those looking for an elite thermo-pot: it presents chic models with Teflon-coated heaters, microprocessor control. The kettle will delight the owner with the required water temperature, in the morning it will warm up the liter in advance, controlled by the timer command. The convenience of a thermopot is achieved by electronics, and energy is saved a lot.

Termopot Delta is a representative of budget options. For $ 39, he will be happy to heat water, serve as a portable thermos. The model provides the global properties of the considered class of household appliances, including water dechlorination, three temperature modes, and a removable cover.

In the middle price segment, the Hotter thermopot is a typical representative. Overlapping the $ 80 niche, the models are perfect for offices, apartments.

Taking the tool

The internal structure of household thermopots is different. But the simplest models surprise with similarity and simplicity. Repair of the Scarlet thermal pot can be performed according to the standard scheme, while Zojirushi's microprocessor technology will not tolerate interference.

It is necessary to soberly assess your own strengths, not to try to unsolder a microchip that requires a hot air gun with a 150-watt soldering iron. It is necessary to master the main techniques of working with electronic componentsafraid of static electricity, high temperatures.

Performing work will require tweezers, a tester, a voltage indicator screwdriver, and a soldering iron. The minimum list will be kindly suggested on any radio electronics forum. In the same place, ask for advice on correcting the detected defect.

As it is impossible to grasp the immensity, it is impossible to list in one review the recommendations for all cases of how to repair a thermopot with your own hands.

Do-it-yourself thermo pot repair in 3 steps

It is quite possible to fix a thermopot with your own hands, even without special knowledge of electricsThe thermo-pot was invented very recently. After boiling water, the kettle does not keep it hot for long. It is the thermopot that helps the water temperature to be maintained for a long time. You can always drink tea, and you don't have to boil it and wait. But, like any technical tool, a thermopot fails, and you have to repair it. How to do it yourself later in the article.

Thermopot schematic diagram

In ancient times, a thermopot would have been called a samovar, now it is affectionately called a potter. He can not only boil water, but also keep it hot, like a thermos. But if the potter breaks down, it is not necessary to call the master and carry it to the repair. The work can be done independently. Before using each household appliance, you must read the instructions. Understand how to use the item correctly and what will prolong its use. For example, a thermopot, according to statistics, often breaks: an indicator panel, a key for primary boiling, secondary boiling, a boiling function and water supply.

All these breakdowns occur due to the effect of high temperature on all elements of the device. For example, the housing that protects the entire device should not heat up during boiling.

Thermopot data are very popular: Polaris, Vitek, Elenberg, Scarlett and Alisa. The thermo-pot circuit is light enough for a non-professional electrician to figure it out. But all the same, the scheme is a scheme, and it is not recommended to climb into it without minimal preparation. Therefore, if a thermopot does not boil water at all or does not perform the functions of a thermos, then first you need to study its scheme and understand the principle of operation.

Before proceeding with the repair of a thermal pot, you should familiarize yourself with its diagram

Thermopot operation scheme:

• All elements are located under the protective casing;
• The water tank is made of stainless steel;
• Heating coils are installed at the bottom;
• The thermopot heats up with one spiral, the second maintains the water temperature;
• The thermo-pot pumps water using a water pump.

The thermopot works as follows: after pouring water into the thermopot itself, the lid closes and the device turns on. One coil begins to boil water. A thermal fuse turns off the product as soon as the water reaches the desired temperature. Cools the water to the desired temperature set by the user. The temperature itself is maintained by a second heating element. Thermal fuse recommend using Sheng Ping SPF 139 reusable. Therefore, if the thermo-pot breaks down, you will have to completely disassemble it, remove the cover with the button, check the heating element and establish why it broke.

Products from different manufacturers have their own characteristics. For example, the Vitek device has a special button for filling the cup with water. This button is also called a pump or pump. With its help, you can draw hot water into a cup without getting burned. The circuit of the Vitek thermocouple motherboard is called RSP22, it is available and easy to do in special services.

Fast thermo pot repair: frequent breakdowns

If the thermo-pot constantly breaks, then you need to take it for repair or deal with the problem yourself. It is better to start repairing the kettle by disassembling the case, remove the lower plastic part, and unscrew all the bolts. After that, access to all electronics is opened. The electrical component of the product is open to fault determination. It is of fundamental importance to repair the thermal sweat after complete analysis. After evaluating all the components with a view in the instructions, you can establish the causes of the breakdown - maybe the stainless steel tank has broken.

One of the frequent breakdowns of a thermal pot is a breakdown of the indicator panel.

The reasons why the thermo pot does not work:

1. The display panel does not turn off.The opposite also happens, the complete absence of the device and the indicator panel. In this case, you need to check all the wires and contacts. Check the boil regulator.
2. The main switch does not work. Check all temperature switches and if the wiring of the bottom switch is working properly.
3. The water is heated, but not boiled. When boiling is turned on, the thermopot turns off and does not perform its main function of boiling. In this case, the contact is checked for rupture or completely the boiling part.

If the thermopot does not heat due to the breakdown of 2 spirals, then there is no point in repairing it. It will take a long time and a lot of money. With a lot of shortcomings, it is easier to take a new one, because repairing the wiring and the tank in total will be expensive.

Primary Aid: When Thermo Pot Doesn't Boil Water

Most importantly, check the settings on the control panel. Perhaps the boiling function is turned off, and the thermo pot is turned on only in heating mode. Then it turns out that there is no malfunction, which means that the elimination of the broken part is not necessary. The settings are ok, but the water is not boiling - check the temperature sensor and heater. If the elements do not work well, then they must be replaced with new ones.

How to disassemble a thermopot:

1. Remove the top element - the cover. Then remove the ring securing the inner tank to the body.
2. Remove all fastening elements - screws and bolts.
3. Remove the bottom of the thermopot.

In order to disassemble the thermopot, remove the upper element and the bottom of the device

A screwdriver is useful for all these manipulations. To get to the electronic filling of the device, you need to remove all the elements, and only then can the device be repaired. The thermo pot can perform many functions, for example, replace the thermo mug. But, what is the use of this, if the water is not boiled there - neither brew tea, nor coffee.

But, before disassembling the device, you need to know exactly where what is attached and how many parts were there before the disassembly.

The thermal switches have a boiling function. They are usually located at the bottom of the product or along the walls. To prevent the thermal switch from melting, it is treated with a special solution. To test the element for work, you need to pull it out and leave it on, screw the wires to it, and place them in the water. With all this, you need to check the resistance. It should not be outside the water, if it has increased in the water, it means that the part is working and the breakage is not in it. If the opposite is true, then the thermal switch is faulty.

Replacing the pump if the thermopot does not pump water

It happens that the thermopot works, boils, heats and keeps the water warm as much as necessary, but it is impossible to pour water - the valve is broken, and the water supply is impossible. And it's not at all clear which option is better: a broken heater or a feed function. Such a breakdown indicates a malfunction of the pump (pump) for pumping water into the mug. Then it is necessary to disassemble the automaton and examine the suspicious element.

How to get to the pump:

1. After removing the metal housing, disconnect the tubing from the pump. If you find scale on the wires, you need to get rid of it.
2. Disconnect the pump itself from the tank and housing, while trying not to lose all small parts.
3. As soon as the pump and the electric motor are disconnected, remove all scale that interferes with the correct operation of the device.

If the thermopot does not pump water, in this case it is necessary to replace the pump

Like any household appliance, a thermopot needs care and attention. You can descale it at home using citric acid, acetic acid, and baking soda. You need to clean the thermopot immediately, with the appearance of the first scale. If the product begins to emit suspicious sounds, then cleaning is all the more necessary. This is the first signal for help.

If, after all these manipulations, there is no water supply, then it is necessary to change the pump itself - to buy a new one. There is no point in restoring a damaged pump.

Soda and acid cleaning is carried out in accordance with the size of the product itself. You can also use special cleaning agents, just carefully study the composition. Citric acid has its drawbacks - sometimes it is not enough for one kettle. But after boiling water with citric acid, it is important to wipe the kettle with a soft cloth. There is no smell after boiling, it can be combined with vinegar. Acetic acid removes limescale instantly, but it is very difficult to get rid of the aroma afterwards. It takes several boils after and cleaning with a special tool, so it is better to clean with a mixture of citric acid and vinegar.

DIY thermo pot repair (video)

Thermopot is a very convenient thing for giving and rest. The water will be hot all the time, in cold weather it will not be necessary to constantly run to the stove and put the kettle on. You can just walk up and pour hot water, it makes life easier and reduces the waste of time. Having put the thermo pot in the morning, after a shower, you can immediately drink coffee without worrying about the kettle boiling and the instant cooling of the water.

Similar materials

Thermo pot is a type of household appliance that has appeared on the market relatively recently. It is a symbiosis of an ordinary electric kettle and a thermos. Water is poured into the device, brought to a boil and kept hot. But, like all household appliances, the thermopot breaks down, its electrical components fail. Therefore, before you independently repair a thermopot, you need to understand its design features.

Terpomot design

Inside the plastic case, there is a stainless steel water tank. Two heating elements are installed at the bottom of the tank: one for boiling, the second for maintaining the desired temperature of the liquid. A pump is installed on the side of the tank, which pumps water from the tank to the outside. All units operate on electricity in certain modes, so the thermopot is equipped with an automation unit that controls the device and regulates the processes taking place inside.

Automation includes:

• a temperature sensor that monitors the temperature of the water in the tank;
• a relay that turns on the heating element and is directly connected to the temperature sensor;
• a sensor that monitors the water supply by the pump;
• a thermal switch that responds to an excess of the temperature of the water and the tank;
• thermal fuses that duplicate the functions of a thermal switch;
• electronics unit.

There are two thermal fuses in the design of the thermopot: one is responsible for overheating of the water, the second for the fullness of the container. If there is no water inside the device, it will not turn on.

The electronic unit includes a pulse switch, a diode bridge and various electronic elements: capacitors, diodes, resistances, transistors and others.

Causes of malfunctions

There are many reasons why the thermal pot does not work. For example, the pump does not pump; the lights on the control panel are on, the heating elements are heating the water, and the pump is not working. The most unpleasant reason is if the pump motor burns out. It will not work to fix the unit; you will have to change the pump itself. But the device costs almost half the cost of a thermos-kettle, so it is better to purchase a new thermopot than to repair a broken one.

If the pump does not pump, this does not always mean that it has burnt out. Contacts that need to be cleaned with alcohol may simply burn, and the problem will disappear. Sometimes the impeller becomes clogged with scale, which must be cleaned from dirt. In any case, the thermopot will have to be disassembled to identify a breakdown. To do this, from the bottom side, you need to unscrew the screws that attach the case to the base, which can be removed when you lift it up. Then detach the hose connecting the pump to the water tank and unscrew the bolted connections to dismantle the pump. It is checked with a multimeter for the resistance of the turns of the electric motor, and the clogging of the impeller is also inspected.

First of all, after removing the case, you need to check the power cable with a plug at the end. For this, the ends of the wire are disconnected from the device and each one is individually called with a multimeter. It is necessary to check for resistance by installing the probes of the measuring tool: one to the disconnected end of the cable, the second to the horn sticking out of the plug. The resistance should be infinite, which will show the integrity of the wires. If the measurements showed zero, then there is a break in the wire, which means that the cable will have to be replaced with a new one.

Then you need to check the electronic board located at the bottom. Remember that this device has two boards: one is electronic circuit thermopot, which is responsible for the relay for heating water and for the voltage at the pump. The latter works from 8-24 volts, and for this you need a step-down transformer powered by this board. The second board is intended for the device control unit. It is connected with control buttons and setting operating modes, with indicators on the case. It is necessary to inspect the microcircuit and the places where parts are connected to it. A crack in the track or a disconnected end of a transformer, capacitor and other radioelements can cause the entire device to become inoperative. You can fix the breakage with a soldering iron. In this case, the tracks on the board are best tinned with tin solder.

In general, with a fundamental electrical circuit a thermal pot must be careful, because every detail plays its role. Even a small visual inspection can reveal an unusable item. For example, if a capacitor is swollen, then it is clearly burned out, and there is no point in checking it with a tester. But the failure of the diodes can only be detected by dialing, although these elements rarely fail. The same goes for the microchip.

The heating element for a thermopot, if it burns out, is not repaired. It can be changed to a new one, but the craftsmen say that such repairs are unprofitable. The heating element is expensive, its replacement is not an easy process. The thing is that the heating elements are located inside the stainless steel tank. They are fastened with a bolted connection through gaskets that ensure the tightness of the joint. To get to the fasteners, you must dismantle the entire interior of the device completely. So it's better to buy a new home appliance.

Simple breakdowns

There are a number of faults that can be eliminated by yourself. They are simple and do not require knowledge of the design and device device.

• The indication does not work. The most common reason is the lack of power supply to the indicator lamps. Therefore, you will have to check the entire circuit from the power cable to the light bulbs, while focusing on the wires and contacts.
• Boiling mode does not work. There are two reasons: the main heating element burned out and the bottom thermal fuse burned out. In the second case, you just need to change the part. In the first case, the entire device changes.
• The second heating element for water heating does not work, the heating element for boiling is working. We'll have to check the main board, or rather, all the parts installed on it.
• The pump does not pump water from the tank. A pump defect is a rarity, most often an additional heating element burns out, through which the pump motor is powered. These two nodes are interconnected. But if the burned-out pump does not cause the heating element to turn off, then the burned-out heater becomes the cause of the inoperative pump.

If the above reasons are not found, then there is a defect in the board. You need to look for faults on it. If you are a layman and do not understand the intricacies of the radio business, then you will not be able to solve the problem. A printed circuit board is not just a connecting element between the radio components installed on it, but a complex circuit that should be well understood. Therefore, if you disassembled the thermopot and do not know what is the matter, take it to the service center in disassembled form.

On the market, thermo pots are represented by different brands that differ from each other in design. For example, a Scarlett device is repaired according to the standard procedure. But this is not the cheapest option. It is not recommended to repair the Zojirushi model yourself. Even a lid that is unscrewed will cause the device not to be serviced.

The printed circuit board is a delicate part, because it contains elements that do not tolerate rough interference. For example, a microchip is soldered off with a hot air gun, and not with a soldering iron, which will burn both the part and the place of its installation with its power. Capacitors fail under the influence of high temperatures, diodes do not like static electricity. Thus, if you are not familiar with the main methods of working with electronic components of microcircuits, then you should not undertake their repair.

The presence of simple tools is a mandatory requirement for repairing a thermo-pot. The arsenal should have tweezers, a soldering iron, an indicator screwdriver, and a multimeter. The more tools, the easier it is to repair.

Conclusion on the topic

Thermo pot is a modern household appliance. If it turns off periodically, then there is a reason for this. Its detection is the main task before the repair. But there can be many reasons for a non-working device, and it is sometimes very difficult to identify each one.

This article is devoted to diagnostics of malfunctions of thermal pots associated with heating and water supply, using the example of the Elenberg TH-6030, Vitek VT-1188 and Vitek-1191 models described earlier. The article provides advice on how to connect power to a "dry kettle", ie. a kettle without water and to separate boards required for measurements and diagnostics of failures, which facilitates their repair.

A lot of materials on disassembling thermal pots have been posted on the Internet. It is more convenient to take measurements when the kettle is stable upside down. To do this, you need to remove its upper, convex cover for filling with water. With a screwdriver, squeeze the latch on the cover hinge and remove it from the axis on which it is attached. A stand for an inverted thermal pot can be a plastic bucket, the bottom diameter of which is slightly less than the diameter of a container for boiling water. During the disassembly of the thermal pot, it is necessary to ring all the heating elements, thermal switches and fuses that are in the power circuits, from one contact of the mains plug to the power contacts of relay K1, and from the other contact of the plug to the common wire of the main board, ring the ground contact of the plug with metal parts of the kettle body and check the "ground" for a short circuit with the mains wires. At this stage, a large number of faults are identified.

Instead of Elenberg TH-6030 (Fig. 1), its clones are currently being sold: models of thermo-pots BRAND 34300 and KC-2011-B. Their schemes are similar to TN-6030. (Fig. 1) The main boards of the products have the same KS-87-B code, they differ only in the types and ratings of individual parts, and in the absence of the CN1 connector on the KS-2011-B common board. Figure: 2. The mains wire is connected to it by additional pin 1.1 of the SP1 connector. The marking of the KS-2011-V board elements in the article is indicated according to the TN-6030 scheme. It is impractical to connect faulty thermocouples of these types to the 220 V network for diagnostics, because their secondary power supply with a capacity of up to 25 mA serves only to power the control circuit of the relay K1.

Boiling indicator HL1 turns on when contacts K1.1 of relay K1 or thermal switch SF1 are closed. Heating indicator HL2 and heating element EK1 are constantly on. In the absence of forced boiling, without removing the board from its place, the capacitance C1 is measured from the R1 terminals in order to exclude its breakage or defects in the soldering of the terminals. Then the diodes VD1 - VD4 of the rectifier bridge and the Zener diode VD6 are called with an ohmmeter, and the breakdown of C2 and C3 is excluded. By dialing between the “+” terminals and the VT2 collector, the relay coil K1 is closed or the VD7 diode is broken. Then, two wires are connected to the terminals of the diodes of the VD1 - VD4 bridge or two wires are soldered and a voltage of 12 - 16 V is supplied to the board from an external source. Its polarity, "+" and "-" is shown in Fig. 2. Then press the SB1 "Boiling" button, if there is a click to turn on the relay K1, between the contacts of the CN3 and CN4 connectors, after disconnecting the heating elements from it, measure the resistance of the closed contacts K1.1, normally it is less than 0.5 Ohm. If after pressing SB1 there is no click, connect the R4 pin marked in Fig. 2 with a green asterisk to "+". If the relay clicks, eliminate the open in the SB1 circuit. If there is no click, connect the VD7 anode with the "-" contact on the board, when a click appears, an open circuit is excluded from the circuits of transistors VT1 and VT2. If there is still no click, relay K1 is faulty. Reduction of forced boil time to less than 1 minute. indicates drying out or leakage of capacitor C3.

If the pump does not work, it is necessary to exclude the breakdown of the heating element for the heating EK1, breakdown of VD9, breakdown or breakdown of VD10. Then the electric motor is disconnected from the SP2 - SP3 connector and a constant voltage of 10 - 12 V is applied to it. If the motor is working properly, check the SB2 - SB3 buttons on the control board, they switch a pulsating voltage with an amplitude of more than 300 V, so their contacts spark and may burn out over time ... A voltage of 10 - 12 V is applied to the contacts of the CN2 and CN4 connectors, in the polarity of the reverse conduction of the diode VD9. If, when pressing the SB2 or SB3 buttons, the electric motor works worse than when it is turned on directly, these buttons are replaced.

In the VT-1188 thermopot circuit, Fig. 3, the position of the power connectors on the main board has been clarified in comparison with Fig. 4 . The location of the connectors is shown in Fig. 4. This section describes the failures associated with the self-diagnostic function of the ic1 processor, which controls the operation of the thermal pot. If the kettle does not start boiling, water supply and no indicator lights up, most likely there is no secondary supply voltage. To check the transformer T1, it is necessary to ring both its windings for an open or short circuit, the primary one from the JP6 - JP9 connectors, the contacts indicated in Fig. 4 "to T1" is not disconnected. Secondary winding - by disconnecting the AC-IN connector. The resistance of the T1 windings is 1 kOhm and 4 Ohm. Then the diodes of the VD1 - VD4 bridge ring out and exclude a short circuit at its output. The EK1 heating element is disconnected from the JP1 and JP2 board connectors, its disconnected contacts are wrapped with adhesive tape (electrical tape) and the leads are fixed on the kettle body so as not to dangle. Then the thermopot without water is included in the network. At idle speed T1 must run for at least 10 minutes. If it heats up quickly and the secondary voltage at the AC-IN connector is less than 10 V, replace it. A working T1 is connected to the connectors and the kettle is connected to the network. In VT-1188, the secondary power supply circuits are isolated from the mains voltage, but mains voltage is present on all "JP ..." connectors of the board. Subject to safety measures, working with a thermopot connected to the network in this way is no more dangerous than working with network block nutrition. Normally, the alternating voltage of the secondary winding of the transformer T1 at the input of the rectifier bridge VD1 - VD4 is 12 V, at its output the constant voltage is 14 - 16 V, the polarity "+" and "-" is shown in Fig. 3 and 4. From the output of the ic2 stabilizer, the +5 V voltage is supplied to pins 11, 12 of the ic1 processor. If +5 V is present at pins 11 - 12 of ic1 and the indication is on, check the health of the ic1 processor and ic3 optocouplers for interlocking.

1) Screwdriver with insulated handle for 3 - 5 sec. close pins 1 and 2 of ic3, (they are under mains voltage), if ic1 and ic3 are good, after 3 seconds. LEDs LED3 and LED5 will flash, Fig. 5, (L3 and L5 in Fig. 3) and the buttons SW1 - SW4 are locked. The glow of the indicators can be seen by turning the kettle plugged in from the upside down position to its normal position. During normal operation of the kettle from the mains, an alternating voltage of 220 V between the JP8 connector and the "N" bus (connectors JP2, JP4, JP6) is rectified by the diode D8 and through the resistance R15 a pulsating direct current of 4 mA is supplied to terminals 1 and 2 - the inputs of the ic3 optocoupler, it opens and from its pin 3, a voltage of 5 V is supplied to pin 6 of the ic1 processor. If no current flows to the optocoupler input, ic3 closes, pin 6 of ic1 shows a "0", and ic1 goes into blocking mode. This happens when the fuse FU1 blows, more than 3 seconds open the contacts of the emergency thermal switch SF1, when the circuit D8 - R15 is broken, or when the ic3 optocoupler itself fails. Defective parts are replaced. If there is no replacement for the ic3 optocoupler, during operation, you can connect a jumper to its pins 3 and 4. This blocking does not turn on when the heating element and power contacts of the K1 relay are broken. The primary winding of T1 is connected to a 220 V network in front of SF1 and FU1, therefore, after the protection is triggered and the blocking is turned on, the secondary power is not disconnected from the board. This blocking is released only after the kettle is de-energized.

2) A single-core wire pin is used to close two metal contacts in the upper half of the CN4 connector (red), into which the wires coming from the RT thermistor are pressed. Figure: 6. After 3 sec. LED1 and LED6 start flashing. (L1 and L6 in Fig. 3), buttons SW2, SW3, SW4 are locked. A negative TCR thermistor RT is connected to the circuit so that as the water temperature rises, when its resistance decreases, the voltage at pin 8 of ic1 increases. At the boiling point of water, the resistance RT decreases to about 7.3 kΩ, and the voltage at pin 8 of ic1 rises to about 3.7 V, after which the boiling mode is turned off, the LED1 indicator goes out and the kettle goes into the mode of maintaining the water temperature and starts to glow, and then one of the indicators of the selected water heating temperature - LED3, LED4 or LED5 - blinks. If the RT resistance becomes less than 7.3 kOhm, and the voltage at pin 8 iс1 is more than 3.7 V, the processor diagnoses the RT short circuit and turns on the blocking. The blocking is canceled by pressing the SW1 "Boiling" button, but if the reason for the RT short circuit is not eliminated, then after 3 sec. the lock will turn on again. After boiling, the water cools down and the RT resistance rises, when it increases to 10.5 kΩ, and the voltage at pin 8 of ic1 decreases to 3.5 V, the processor will re-enable boiling. The value of the water selected to maintain the temperature does not noticeably affect these indicators. The main reasons for the failure and activation of this blocking are a decrease in resistance or a shorting of RT, or an open R13.

3) Disconnect the RT thermistor from the CN4 connector, after 3 sec. LED3 and LED6 will start flashing. (L3 and L6 in Fig. 3), buttons SW2 - SW4 are locked. In the range of resistance values \u200b\u200bof the RT thermistor from 10.5 to 550 kOhm, in the mode of maintaining the water temperature, the kettle will turn on the heating element. When the RT resistance rises more than 560 kΩ, when the voltage at pin 8 of ic1 drops below 0.2 V, the processor diagnoses an open RT. The blocking is canceled by pressing the SW1 "Boiling" button, if the RT break is not removed, after 3 seconds the blocking will turn on again. The main reasons for activating the lock are an open RT or R11, poor contact in the RT connector, or the destruction of the soldering of its terminals on the board. In all cases of failure of the RT thermistor, it must be replaced. It is undesirable to connect resistors in parallel with RT, they will only reduce the value of its TCS.

When the kettle is in the "Cooling" mode, only LED2 is on, all interlocks are also activated.

If there is +5 V at pins 11, 12 of the ic1 processor, and the commands from the SW1 - SW4 buttons are not executed and there is no indication, an oscilloscope or frequency meter checks the presence of generation at pins 13 or 14 of the processor, it is measured between pin 13 or 14 of ic1 and "- »Fees. If there is generation (4 MHz +/– 2 kHz, amplitude 0.8 - 1 V), the cause of the malfunction may be a broken contacts or a soldering of the CN1 connectors on both boards, or a broken wire in the harness connecting these connectors. If there is no generation, the ic1 processor is faulty.

Without connecting the kettle to a 220 V network, voltage can be applied to the board through the AC-IN connector. To do this, by disconnecting T1, a voltage from an external power source is connected to the connector, alternating 10 - 12 V, or constant 14 - 18 V, of any polarity. With this inclusion, if the ic1 processor is working, after 3 seconds. the blocking "1" will work and the LEDs LED3 and LED5 will start blinking, therefore, for normal operation of ic1, pins 3 and 4 of ic3 must be closed together during the repair.

The diagram of the VT-1191 thermal pot is shown in Fig. 7, compared to Fig. 5. on it the connection of power connectors and heating elements has been clarified. Switching transformerless power supply VT-1191 is made on the VIPer-12A microcircuit. Its output voltage +18 V is supplied to the inputs of the voltage stabilizers +12 V and +5 V of the main board. The negative output of the power supply unit is connected to the "N" bus, one of the wires of the 220 V network. A defective kettle without water is connected to the network in the following sequence: power contacts of relay K1. To do this, unscrew the nuts securing the terminals "H" and "B" to the contacts of the heating elements on the kettle body. The terminals of the disconnected wires are connected together with adhesive tape (electrical tape), and the wires themselves are bent towards the relay, they are rigid, therefore they are not specially fixed. Figure: 8, Fig. nine.

The removed nuts are screwed into place. Slide the plastic cover off the terminal of the network wire connected to the board contact "N". The negative probe of the multimeter will be connected to this terminal. Figure: 9. After the kettle is plugged into the network, the HL3 indicator will immediately light up and the heating element - EK2, which is connected to the normally closed contact of the K1 relay, will turn on. Alternately press the buttons SW3, SW2, SW1, (boiling, unblocking, water supply), note the execution of commands and the inclusion of indicators HL1 - HL2. For measurements, the kettle is turned upside down. Measurements start from the power supply output, the voltage of 18 - 19 V should be at both terminals of the choke L2, at the "+" capacitor EL3, at C3, at the anodes of diodes D4 and D5. The voltage of +12 V is checked at the cathodes of diodes D2, D6 and D7, normally it is equal to 12-15 V. The voltage of +5 V is measured at the emitter of Q4, terminals C4, R9 and at terminal No. 1 iс1. All points for measuring the supply voltage are marked in red in Fig. 9. Next, check the circuit of the SF2 thermal switch, which is connected to the 220 V AC network: R16, D8, R15, transistor Q2, R10, connector CN3, SF2, pin 4 iс1. From it, signals about boiling - cooling of water are sent to iс1. The points for measuring the voltage in this circuit are marked in green in Fig. nine.

At room temperature, the contacts SF2 are closed, on the base of Q2 and on R15 there will be a voltage of 0.6 V, on the collector of Q2, on R10 and at pin 4 of iс1 - 0 V. In this state, iс1 executes all commands. At a temperature of 88 degrees C, the SF2 contacts will open and the voltage at the base of Q2 will be 0 V, at the collector Q2, at R10 and at pin 4, ic1 will be 5 V. When SF2 is open (due to hesteresis, its contacts will close again when t drops to 75 - 80 degrees C), the iс1 processor will block the "boil" command. After pressing and releasing the SW3 "HEAT" button, the HL2 indicator should immediately go out, and the heating element for boiling EK1 should turn off. It is connected to the normally open contact of relay K1. In the case described in, the failure of iс1 manifested itself in the fact that he did not "see" the voltage at pin 4 and could not turn on and off the boiling of water at the right time.

Without connecting the kettle to the 220 V network, constant voltage can be supplied to the board from an external power source. Figure: 10. True, in this case it will be impossible to evaluate the operation of the power supply, and the circuit of the SF2 thermal switch will be disconnected from the 220 V supply voltage, so you will have to temporarily connect a 10 kΩ resistance between the D8 anode and the +12 or +18 V voltage source. On the part side, the +18 V voltage is connected with a clamp or soldering to the anode of the diode D6, and the minus supply is connected with a clamp or a terminal to the board contact "N". You can solder both wires to the board from the conductor side - parallel to the terminals of the EL3 or C3 capacitors.

Designation of power leads on the boards of Vitek thermocouples.

L) - mains outlet, conditionally connected to the phase wire of the 220 V network after the fuse and the emergency thermal switch.

N) - network output, conditionally connected to the neutral wire of the 220 V network.

H) - output of the power contact of the relay for connecting the output of the boiling heating element.

B) - output of the power contact of the relay for connecting the output of the heating element for heating water.

T) - output of the moving contact of the power relay K1, switching or turning on the heating elements. It is connected to pin L.

List of references

1. Website https://msk.au.ru/8030049/

The thermal kettle, or thermopot, is gaining immense popularity. However, its cost is quite high, therefore, in order to save money, you can fix some problems yourself. It often happens that a thermopot heats the water, but does not boil it.

Causes of malfunction of thermocouples.

Before you start looking for the reasons for the breakdown of the thermal kettle, you need to know what kind of object it is. Thermo pot is an electric kettle that includes the function of a thermos, consisting of two bodies. The outer one is usually made of plastic, while the inner one is made of metal. In the inner case there is a flask for water. The kettle is closed with a lid, on which the entire control panel is located.

To fix any breakdown of the thermocouple, the first step is to check if the setting is correct. In the menu of its settings, you need to set exactly the temperature of heating the water that is needed. If everything is in order with the heating tinctures, then the causes of breakdown can be:

• thermal switch located on the bottom of the kettle;
• thermal fuse located on the wall of the thermal pot;
• insufficient contact of any part connectors;
• malfunction of the electronic board;
• the indicator panel stopped turning off. There are times when, on the contrary, the indicator panel turns on, but the thermopot does not start. If this is the cause of a breakdown, then it is worth checking all its components, wiring and thermal fuse.
• the kettle stopped turning on. To eliminate this malfunction, it is necessary to check the correct operation of the electrical circuit and temperature switches.

In order to more accurately identify the cause of the breakdown of the gadget, you will have to disassemble it.

How to properly disassemble a thermopot

1. The first step is to remove the top cover, as it will interfere. The next thing to do is to turn the device upside down and use something flat and sharp to remove the corkscrew ring, for example, with a screwdriver or knife. To perform this action, it is worth using some physical force.
2. Several screws will appear under the corkscrew ring; they can be easily unscrewed with a curly screwdriver.
3. The next step is to remove the bottom of the kettle with a knife or flat screwdriver, which requires little effort, because the bottom is secured with latches.

After that, all the electronic filling is in front of your eyes. Now you need to check all terminals for tightness.

Important! In order to properly disassemble a thermopot, you must have at least a little knowledge of electrical engineering!

Minor breakdowns of the kettle happen. In such cases, you can.

Reasons why the thermo pot does not boil water

Thermal switch breakage

Thermal switches are located on the walls or bottom of the thermopot. This part is attached to the main body with bolts from which the contact wires extend. In order to preserve heat exchange inside the vessel, the points of attachment of thermal switches are smeared with a special white compound. In order to remove it, you just need to disconnect the contact of the thermal switch and pull it out. In the rest position, the switch will be closed. You can check its serviceability using a special tester (its readings should be equal to 0). It is necessary to screw two wires to the thermal switch and lower it into boiling water. At this time, its resistance should increase, and the tester should show an infinite number - such readings indicate the serviceability of the part. If the tester readings did not budge, then you need to replace the thermal switch with a similar one.

Important! Before purchasing a thermal cut-out, consult an electrical engineer or dealer.

If, then you should pay attention to the thermal switches. Most likely, you will have to replace one of them.

Malfunction of two coils

Any thermopot has two heating coils, each of which performs its own function. The first is designed to boil water, and the second is constantly heating the contents of this unit.

If the thermo-pot breaks down due to a malfunction of the heating coils, then there is no point in repairing it. This event will take a lot of time and family budget. With a huge number of shortcomings, it is better to buy a new kettle, because replacing all the wires and the tank at the same time will cost a lot of money.

Important! Regardless of the manufacturer's company and volume, each thermopot is equipped with several heating modes, with the help of which any person can set the optimal water heating temperature for himself.

But experts advise purchasing thermal pots that have no more than three heating modes, since this is quite enough for optimal use of the device. The cheapest models of thermos kettles have one water heating mode. This feature should be taken into account when buying a thermal kettle.

Why does the thermopot not heat the water?

The main problem of any thermal pot is water heating. Often the reasons are any short circuits in the circuit, which includes the heating element. Closures can occur in the heating element itself, relays and fuses. The easiest way to find out is to "ring" each element, as well as all the wiring, using a multimeter. Using this method, you can easily find out which part needs replacement or repair.

Thermal fuse defective

So what role does a thermal fuse play in an electric kettle? This spare part is one of the most essential parts of the device. It protects the device from burning. If at least one of the fuses stops functioning, then the water stops heating.

Usually, these parts are attached to the side walls of the thermopot. But in some models, they can be installed on the bottom, and their appearance resembles small cylinders. They start to work when the water temperature reaches the boiling point. Their role is to turn off the device if there is not enough water in it. If the thermal fuses start to work before the water boils, then this can lead to overheating of the thermopot, and it will not boil, but simply heat the water. To check the serviceability of this device, it must be placed in boiling water. And if it turns on before it boils, this will mean that it is defective and needs to be replaced.

Repair of thermal fuses.

It is necessary to check all the main components of the apparatus with a multimeter. We are testing the thermal relay. To do this, the tester must be set to a mode that allows you to measure resistance.

The multimeter shows a complete absence of resistance, which means that it is the main reason why the thermo-pot does not heat the water. This means that the sensor must be replaced with a new one. To replace it, you need a curly screwdriver. With its help, it is necessary to unscrew the bolts that secure the sensor and replace it with a working one.

Important! It should be remembered that the constant temperature of a thermal fuse in working condition is about 90 0 C.

If after changing the thermostat in normal mode, it means that the efforts were not in vain and the repair was done successfully.