Do-it-yourself multicooker repair: nuances and subtleties of the process

Repairing a home multicooker begins with studying the electrical circuit. Let's take a brief look at two photographs: an image of the pattern of the tracks and the installation of the printed circuit board, which generates the power supply voltage for the control panel and contains a relay that connects the heating element at the right times. Let's first consider the operating algorithm of the device, then we will discuss repairing the multicooker with our own hands. Informing readers, we bring information: equipment that allows you to prepare porridge by pressing one button is produced exclusively for the CIS. Polaris, Brand, Scarlett, Supra, Vitesse, Redmond - sonorous names, and a good half have nothing to do with the West. America recognizes the famous Philips; in Europe, too, the home multicooker has not yet gained popularity. We believe that the current state of affairs is caused by a war of ideas. The United States believes that an air fryer plus a microwave oven can replace the Universe of culinary household appliances.

Rules for using a multicooker

To avoid unexpected malfunctions of the device, you must always strictly follow certain rules and requirements. The sequence of actions when operating the device is also very important:

• choose the required recipe, prepare the necessary products;
• remove the bowl from the appliance, load it with food;
• lower the bowl into the multicooker;
• check that it is connected correctly to the electrical network;
• set the required program;
• turn on the appliance for cooking.

Operating rules

Each instruction manual for the device contains certain rules, such as, for example:

• The device should only be installed on a solid, level surface;
• connect the device only to a grounded outlet;
• before turning it on, be sure to check the tightness of the closed lid;
• after each cooking, the bowl must be thoroughly washed, dried or wiped dry with a towel;
• The lid and the pressure valve located in it also need to be washed well and wiped dry.

When should I contact the service center?

If any cases of the device turning off or its incorrect operation occur, you must first check everything step by step, from correct inclusion to detection of burnt food or dirty contacts. When using a multicooker, you need to check all your actions with the operating instructions.

Many faults, such as dirty or oxidized contacts, can be eliminated independently.

Attention. If the multicooker does not work, the desired cooking mode is not set, or it turns off on its own, before deciding what to do, you must immediately disconnect the device from the network.

Before contacting the service center, it is advisable to perform a number of manipulations:

• turn off the device and try to plug it into another outlet (if the problem is a faulty outlet, the device will work);
• check all wires for damage or maybe a wire has come loose somewhere;
• check the instructions to see if you are doing everything correctly;
• try emptying the multicooker, washing it, drying it thoroughly or wiping it dry with a towel.

If all these manipulations do not help the operation of the device, then you need to contact a service center. But remember that if the device is under warranty, the workshop may refuse free service and repair if the device was opened at home yourself.

Watch a video about multicooker repair

This is interesting: Drain check valve for a washing machine: types, principle of operation, how to install

Product design

To carry out repairs, you must become familiar with the operating principle of the electrical appliance and its structure. All multicookers resemble an ordinary saucepan in appearance with a side or top display and buttons for setting cooking modes. It closes at the top with a snap-on sealed lid. The multicooker bowl is enclosed in a thermally insulated casing and placed inside. The direct cooking process takes place in it. Under the bowl and on the sides there are heating elements, control and power units for the multicooker. The bottom is covered with a plastic lid. This is the bottom of the multicooker.

The multicooker does not turn on: reasons and solutions

When studying the question of why the multicooker does not turn on or stops cooking, what to do in such cases, you need to pay attention to the causes of malfunctions. These reasons can be of the most varied nature and properties.

Checking whether the plug is inserted into the socket

If your home multicooker does not turn on, do not immediately panic. The reason may be the most trivial - it was connected to the network incorrectly or you simply forgot to plug it into the socket. It often happens the day before the next cooking, the plug is disconnected from the network (perhaps the socket is needed for another appliance).

Incorrect operation

Before turning on the multicooker for the first time, be sure to study the operating instructions in detail. Because even such simple actions as incorrect connection or incorrect installation of the bowl can cause the device to malfunction. When detecting incorrect actions, the device can:

• reset settings;
• do not respond to commands;
• sound signals;
• show error codes on the display;
• switch modes yourself.

Sometimes it is enough to turn off the device, check that the bowl is installed correctly, turn it on again and the device will work safely. But there are reasons for the incorrect operation of the device that are more complex, for example:

• the device detects the presence of breakdowns, as a result of which its protective functions are activated;
• improper operation, the bowl does not fit the device or is inserted incorrectly;
• ingress of bulk or liquid products into the mechanism;
• non-compliance with the established temperature conditions between different types of cooking (if the “frying” mode was working, then when switching to “cooking”, the device needs to cool down), otherwise the overheating protection will turn on;
• when cooking or stewing, a steam supply is required, even if the recipe does not require water, it must be added (at least a little) to create steam, otherwise the overheating protection will turn on again;
• Failure to comply with the proportions of the products included in the recipe, or a clogged pressure regulating valve, can also cause the multicooker to operate incorrectly.

Low or no mains voltage

If the multicooker does not heat, then often the reasons for this depend on voltage drops in the network. The device may display an error of incorrect operation or simply not turn on due to lack of voltage. You need to check the presence of light in the apartment and wait for it to come on.

Wiring problems

Wiring for a multicooker is usually designed for low power (no more than 3.5 kW). If the wiring itself is working properly, but the device does not work, you need to look for the problem elsewhere. But if there is a surge in voltage in the network, then the wiring of the device may display an error under the corresponding number (all error codes are usually indicated in the instructions).

Thermostat failure

Voltage surges almost always have a negative impact on the fuses, which can eventually blow. If this happens, it is enough to replace the blown fuse. For this:

• open the inside of the multicooker;
• find the heater;
• Having disassembled the button, you can see two colored wires, next to which there is a fuse under a special insulating tube;
• cut out the blown fuse with pliers, insert a new element.

An error occurred

When a malfunction occurs, some numbers or letters usually appear on the display screen. This device gives an error code like this. Knowing its decoding, you can understand the malfunction that occurred.

Repair and service specialists usually know the meanings of all codes. Some of the most common ones are often indicated in the instructions for the device, for example:

• E0, indicates a break in the temperature sensor wire, or the lid does not close due to improper placement of the silicone seal;
• E1, moisture may have gotten inside, the heating element has failed, or the relay contacts are clogged;
• E2, short circuit of the temperature sensor or broken wires;
• E3, moisture getting inside, break in the temperature sensor wire or missing bowl;
• E4, pressure sensor clogged, microcircuit fault found;
• E5, the system turns off automatically when overheated.

The microcircuit is broken

Often, cleaning the contacts of the thermal relay, which is responsible for heating the bowl, helps to find a solution to a malfunctioning device. It is quite difficult to get to it; you will have to disassemble the entire device, find it, open the contacts and clean it well with sandpaper.

If an error code appears on the microcircuits, you need to carefully study and inspect them. You may see problems such as:

• blackening of resistors;
• swelling of capacitors;
• peeling of tracks;
• violation of solder seams;
• soot formation.

If anything from this list is discovered, then you need to repair or replace the corresponding parts, and restore the tracks on the microcircuits by soldering.

Dirty contacts

The contacts of the device often oxidize; this can happen from boiling liquid getting inside when the bowl is loaded incorrectly or overloaded. The multicooker does not turn on often due to this reason. To clean oxidized contacts, you need to disassemble the device by unscrewing the screws on the bottom cover. Clean the contacts from dirt and grease residues with a soft brush soaked in alcohol, and sand with sandpaper.

Timer problems

The timer in the multicooker serves to count down the cooking time, as well as to delay the start of cooking. Correct operation of the device clock is disrupted if:

• the timer refuses to work in some cooking modes;
• The timer for the delayed start function does not work.

Here you need to take into account that the timer usually starts counting when a certain temperature inside the bowl is reached. It is recommended to close the multicooker lid, wait 15-20 minutes until the bowl warms up and only then load it with food.

Attention. If the timer stops working, especially after using the device for the first time, it is best to contact a specialist.

Lid problems

The presence of steam escaping from the device not through the valve, but partially from under the cover of the device, indicates that the lock is broken or the seal of the cover is broken, that is, the silicone seal is worn out. The multicooker itself can work as usual, but the “multi-cooker-pressure cooker” cannot turn on any mode other than “frying”.

The seal must be replaced by contacting a workshop or independently by ordering it from the manufacturer. If the lock is broken, this problem can only be solved at a service center.

How to repair a multicooker with your own hands

Having studied the structure and operating principle of the multicooker, it will not be at all difficult to repair it with your own hands. Often, for repairs, all you need is a screwdriver, but if you’re unlucky, then also a multimeter and an electric soldering iron.

Decoding error codes for the REDMOND multicooker

If the multicooker does not work, then in case of some malfunctions, an error code may appear on the display, indicating which element or unit is supposedly faulty.

As you can see, self-diagnosis in multicookers is not very informative, and error codes do not provide any useful information for repair, but only inform that the multicooker needs to be repaired.

The multicooker does not work, the display does not light up

If the multicooker does not work, and the display does not even light up, then the first thing you need to do is make sure that there is supply voltage in the outlet to which the power cord is connected. To do this, just connect any household appliance, such as a table lamp, to it.

The multicooker is a stationary household appliance and therefore the power cord cannot fray during its operation. But if pets live in the apartment, then it is quite possible that the cord could be damaged by their teeth. Therefore, it is necessary to visually inspect the cord for damage and at the same time check whether it is well inserted into the multicooker connector.

If the above steps do not lead to success, then you need to unplug the cord from the socket and remove the bottom cover of the multicooker by unscrewing one screw. The lid is additionally secured with several latches, but they are small and the lid is easily separated from the body.

After removing the cover, you must carefully inspect the places where the wires are connected to the network connector and the terminals of the heating element. The wires must fit tightly to the contacting surfaces of the terminals and no blackening or carbon deposits should be visible.

If loose contacts are found, then the screws need to be tightened, and if they are burnt, then clean the contacts using fine sandpaper. After this, you need to check the functionality of the multicooker.

Checking the switch, thermal fuse and heating element

If the inspection did not reveal the malfunction, then it is necessary to check the switch and thermal fuse, which are connected to each other by a thick red wire. To do this, you need to use a multimeter or pointer tester, in resistance measurement mode, to touch points 1 and 2 with the probes; the resistance should be zero. At the same time, you need to ring the heating element, measuring the resistance between points 1 and 3 (or 2 and 3). It should be equal to the resistance of the heating element spiral, and, depending on its power, be 30-80 Ohms.

If the resistance between points 1 and 2 approaches infinity, then the switch or thermal fuse is faulty. To check the switch, you need to set its key to the “on” position and touch its exposed terminals with the probes of the device. The resistance should be zero. If the switch is working properly, then the thermal fuse is checked next.

To check the thermal fuse, you need to release the rack that attaches it to the multicooker body and move the insulating tube. Next, touch the multimeter probes to its terminals. The resistance should be zero. Otherwise, the thermal fuse has failed and must be replaced. The method of replacing the thermal fuse is discussed in the article “Do-it-yourself heater repair.” The thermal fuse has no polarity, so it can be installed as convenient.

How to check the switch and thermal fuse without instruments

You can check the serviceability of the switch and fuse without a measuring device. To do this, just connect points 1 and 2 with a piece of wire with a cross-section of at least 1 mm2. After that, replace the lid and connect the multicooker to the network. If it works, it means the thermal fuse has failed. It is unacceptable to operate a multicooker with a shorted thermal fuse, except as a last resort, and under the obligatory condition that a person is near it.

Checking the Control Unit

The display may not glow if the CU board is not supplied with a 5 V DC supply voltage from the BOD or the microprocessor has failed. The presence of voltage can be checked using a multimeter. If the voltage is normal, then it is necessary to remove the board from the multicooker and carefully inspect for blackening or destruction of elements, the integrity of printed conductors and the quality of soldering.

To remove the control board from the multicooker body, you need to unscrew two screws, as shown in the photo.

Next, remove the upper part of the control unit from the multicooker body and move it up. To access the printed circuit board, you will also need to remove the plastic cover, which is held in place by four self-tapping screws.

If the CU board does not receive a 5 V supply voltage, then the fault should be looked for in the BOD. If the supply voltage is supplied to the control unit board and an external inspection does not reveal any defects, then the microprocessor has failed and you will have to purchase a new control unit for repair. The microprocessor installed in the multicooker control unit is programmed for the algorithm of its operation, and simply replacing it will not help to repair the multicooker.

Malfunctions may still occur in the control board that do not affect its performance, but reduce the comfort of use. This is poor operation of the buttons, lack of display numbers or indication of the turned on cooking mode. Such malfunctions are eliminated by replacing the failed element.

The multicooker does not work, the display lights up

If one of the E-error codes is displayed on the control panel display, then the power cord, switch and thermal fuse are in order. Thermal resistances, heating elements or power and switching units may be faulty.

How to check thermal resistance

Thermal resistances in the multicooker are connected directly to the Control Unit using two separate connectors. A white connector with blue wires coming from it is connected to a thermistor, which is located in the lid of the multicooker. And using a black connector with white wires, a thermistor installed in the bottom glass of the multicooker is connected.

Before checking the thermal resistances, it is necessary to disconnect the connectors from the Control Unit. To measure thermal resistances you will need a multimeter or pointer device.

Next, use the multimeter probes to touch the contacts of one and then the other connector and measure the resistance value. The polarity of connecting the multimeter probes does not matter. If you place your palm on the place where the thermal resistance is installed during measurement, its value will increase.

The REDMOND RMC-M23 multicooker is equipped with thermal resistances of the same size, type MF58 with a nominal value of 50 kOhm. In multicookers of other models, the rating may be different. Thermal resistance is operational if its value is not zero or infinity.

How to check the heating element

Heating elements in household electrical appliances are usually the last to fail. A separate article “How to check and ring a tubular electric heater heating element” is devoted to the device and methods for checking the heating element.

The photo shows the findings of the heating element. The resistance of the spiral of a working heating element of the REDMOND RMC-M23 multicooker should be about 80 Ohms.

How to check the Power and Switching Unit

If in the previous steps the cause of the multicooker malfunction was not discovered, then you need to check the Power and Switching Unit (BPK). This unit operates in severe temperature conditions and may fail first.

In the REDMOND RMC-M23 multicooker, the +5 V voltage that powers the Control Unit (CU) and +12 V to power the switching circuit are obtained from the 220 V mains voltage using two separate circuits. Therefore, in the multicooker that had to be repaired, the part of the BOD circuit that generates the +5 V voltage worked, so the control unit worked and displayed error code E1 on the display. There was no +12 V voltage.

Upon careful inspection of the parts of the BOD, the attention was drawn to the resistor-fuse R100, the gray color of which was uneven. The multimeter showed that its resistance was infinity, although according to the color marking it should be 100 ohms.

To repair the BOD board, it must be removed. The board is attached to the base of the multicooker using two screws with metric threads and nuts, which must be held when unscrewing the screws. It is possible to get to the nuts only from the installation side of the cooking bowl by removing the heating element, which is secured with three screws. It is not necessary to disconnect the wires from the heating element terminals.

When the resistor was removed from the circuit board, it became obvious that it had burned out. This is clearly visible in the photograph. The resistor in the circuit functions not only as a current limiter, but also as a fuse. Consequently, its destruction was caused by the large current flowing through it, which could only flow in the event of a short circuit in the elements connected after this resistor.

To make it easy to find the malfunction of the multicooker, I drew part of the electrical circuit diagram of the BOD, which is responsible for generating a voltage of +12 V. Checking the resistance between the terminals of capacitor C3 showed the presence of a short circuit. Capacitor C3 and resistor R1 were soldered off, but the short circuit did not disappear. It became obvious that the PN8024R chip was faulty.

To be completely sure, I found a typical connection diagram for the PN8024R microcircuit, which you see above. Since a short circuit occurred between the SW and GND terminals, it became obvious that a breakdown had occurred between the drain and source of the field-effect transistor inside the microcircuit and to restore the operation of the multicooker, it must be replaced.

Upon closer inspection of the microcircuit body, small local darkening was discovered on the side with markings, which are clearly visible in the photograph.

How to replace a standard +12 V source with an external power supply

The PN8024R chip turned out to be rarely used in household appliances, and it could only be obtained several weeks after ordering it online. There were several adapters available from different computer devices, and the idea arose to select a suitable adapter for +12 V voltage and replace the non-working part of the BOD circuit with it.

The choice fell on the adapter, on the body of which it was stated that it produces a constant voltage of +12 V and is designed for a load current of up to 200 mA, which fully corresponded to the parameters of the PN8024R microcircuit. However, when testing this adapter at a 60 Ohm load, it turned out that the output voltage is 17 V. Obviously, the unit produces an unstabilized voltage, which is stabilized in the device to which the unit is connected. Such a block was clearly not suitable for the output voltage.

There was no longer an adapter with an output voltage of 12 V, but one with an output voltage of 9 V. Taking into account the fact that it was necessary to power a circuit consisting of only two transistors and a relay, I decided to check whether it would work on nine volts. After all, electromechanical type relays usually operate when a much lower voltage is applied to the winding than according to the passport. Testing the adapter under and without load showed that the output voltage does not change and is equal to 9 V.

Before connecting the adapter to the BOD, you must disable the standard stabilizer. To do this, you need to unsolder resistor R100 and diode D106, as in the photo.

There was no 100% certainty that the 9 V adapter would work. In order not to open the adapter case or cut its output cord during testing, the adapter was connected to the multicooker BOD via a standard connector. The plus is located on the central pin of the connector.

The terminals from the connector were soldered, observing polarity, parallel to the terminals of capacitor C105 of the BOD board. The bottom cover was installed in place, the multicooker was connected to the network and then the adapter was plugged into the network. The multicooker started working. To check the reliability of its operation, water was poured into the cooking bowl to the brim, and in the “Cooking” mode of the multicooker, the water was brought to a boil and boiled for 45 minutes until the timer went off. Tests confirmed the correctness of the chosen solution.

All that remains is to install the adapter in the multicooker and connect it to the BOD. To do this, the contact pads of the adapter board, to which it is necessary to supply a supply voltage of 220 V, were connected using wires to the terminals of the BOD board, as in the photograph (yellow and red wires). The +9 V supply voltage was supplied using a pair of red and black wires.

For better thermal operation of the adapter, the part of the case on which the power plug was located was not installed. The photo shows the view of the multicooker, with the bottom lid raised and the adapter attached to it.

Before attaching the adapter to the lid, a place was chosen that would prevent it from resting on the multicooker part after closing the lid. A hole was drilled in the lid so that the threaded part of the self-tapping screw would pass freely, and in the adapter body so that it could be screwed in. The photo shows the head of the screw that secures the adapter to the multicooker.

The multicooker does not remember manually set cooking modes

After many years of use, the REDMOND RMC-M23 multicooker may, after disconnecting it from the network, stop saving manually selected cooking programs in the “multi-cook” mode. This is usually due to the battery being discharged.

The battery is usually installed in the Power and Switching Unit. The appearance of the battery is shown in the photograph. Similar 3V CR2032 batteries are widely used in consumer electronics. To check a battery, you need to measure the voltage at its terminals. It should not be less than 3 V, otherwise the battery must be replaced.

Repairing the multicooker lid hinge

In the multicooker that had to be repaired, in addition, the hinge holding the lid was broken. It was possible to cook food, but there was no seal, and if handled carelessly, the wires connecting the thermal resistance installed in the lid to the control board could easily be torn.

The multicooker lid consists of two halves, which had to be separated to repair the hinges. The lid halves are fastened together using several latches.

The latches are small and therefore the lid can be easily separated using a flat-head screwdriver squeezed between its halves. The photo shows one of the latches.

In order to get to the mating part of the loop, you need to remove the steam condensate collector and unscrew one screw. It turned out that the yellow-green wire grounding the lid was broken.

Both cover hinge pin holders were seriously broken. Yes, this is not surprising, since the part of the cover that holds the hinge axis was plastic and only a couple of millimeters thick. The mistake of the multicooker developers is obvious.

A steel paper clip was used to repair the hinge eye. One end of it was first straightened and then bent at an angle and cut with side cutters along the yellow line, as in the photograph. Next, the corners of the paperclip were fused into the base of the lid. This work requires patience. It is necessary to hold the part made from a paper clip with tweezers and heat it by applying a soldering iron tip to it until it is sunk into the plastic base of the lid to the required depth.

In the photo you see the result of repairing the multicooker lid hinge. The appearance is not very beautiful, but the loop will be covered by the second half of the lid and will not be visible from the outside. But the restored loop turned out to be much stronger than the previous one.

Why does food stick to the walls of the multicooker bowl?

Many multicooker users eventually encounter the problem of food sticking to the walls of the bowl. In this case, solid products, regardless of the amount of oil poured, begin to stick to both the walls of the bowl, coated with Teflon (fluoroplastic) and with a ceramic coating.

There can be two reasons for sticking - a violation of the temperature regime of the multicooker or wear on the coating of the bowl. The answer is simple. If stuck food also burns, then the temperature regime is to blame, and if it sticks without burning, then the coating of the bowl has worn out.

All attempts to restore the quality of the coating using vinegar, table salt or other methods can only give a temporary effect. If the coating of the pan is worn out, then only buying a new bowl will help prevent it from sticking.

If the Teflon film in the bowl is very thin, it is easily scratched to the base even with minor mechanical impact. When stirring food, the sharp edge of a wooden spatula always slightly scratches the coating, and over time, a combination of microscopic scratches, which are difficult to notice with the eye, lead to food sticking. The Teflon coating is sensitive to high temperatures and when heated above 270°C it is destroyed, and as a result, food also begins to stick.

In order for kitchen utensils coated with Teflon to serve for a long time, the thickness of the film must be significant. Teflon is expensive and therefore high-quality kitchen utensils with Teflon coating cannot be cheap.

All of the above also applies to ceramic-coated cookware. After all, this type of coating has nothing in common with ceramic tableware and is a nanocomposite polymer, which contains about 5% sand nanoparticles. Currently, the service life of dishes with a ceramic coating is many times lower than with Teflon.

Therefore, it is better to buy Teflon-coated cookware from well-known manufacturers who will not skimp on the thickness of the Teflon coating.

Is it worth repairing it yourself?

You can repair the Redmond multicooker yourself only when the warranty has already expired, and before that it is better to take it to specialists, but check visually what repairs were made so as not to pay extra money.

When repairing multicookers of different models with your own hands, the main thing is to correctly diagnose why the multicooker does not start working. The reasons are quite different:

• an error message “E1”, “E2” or “E5” appears on the display (read more about Redmond multicooker errors here);
• failure of a microcircuit, resistor or capacitor;
• the thermistor has burned out;
• extreme case - the power supply burned out;
• heating element failure;
• The latch on the top cover is broken.

In addition, you need to know how to disassemble the multicooker. Only after a visual inspection and then a thorough diagnosis can you understand what happened to the product and how to repair the multicooker. It will be useful for the home master to watch this video:

Problems in the functioning of multicookers

Among them are the following:

— The latch (latch) of the multicooker lid is broken - this can be fixed by restoring the latch, replacing the lid, or replacing the latch. The repair option is selected by the technician depending on the design of the particular multicooker.

— The multi-cooker does not turn on. We check the power cord, and if it is ok, we need the help of a specialist. The power supply or electronics may have failed.

— When you press the buttons on the control panel, the multicooker does not respond. Diagnosis and repair of the touch membrane or control module is necessary.

— The multicooker takes a long time to prepare the dish. A possible reason is lack of pressure. The lid valve is clogged with food debris or grease has accumulated. This prevents the multicooker from releasing steam. Food cooks more slowly due to a violation of the thermal regime.

— In a slow cooker, food burns or is undercooked. In this case, the reason is electronics. Diagnostics is required to install the faulty element.

— If the temperature sensors (one or more) malfunction, the device may turn off during operation.

— The multicooker turns on, there is an indication, but it does not heat up. The electronics or heating element may fail. Diagnostics required.

Common breakdowns

Most multicooker failures occur due to contamination of various contacts - liquid or bulk products have gotten inside the product:

• various cereals: millet, buckwheat, rice;
• sugar;
• pepper, salt.

Such breakdowns are not difficult, and they can be eliminated by doing the repairs yourself, but the user must remember that the device should not be plugged in until it is completely cleaned - the consequences can be very disastrous and cause serious damage to the family budget.

Repair cost

Redmond multicookers are among the most popular in their class in Russia.

Many service centers offer repair of these devices as a separate service. How much does it cost to repair a Redmond multicooker? In most Russian services, the repair price varies from 650 to 1,500 rubles, depending on the complexity of the breakdown. The cost of repairs usually does not include the price of parts. The cost of diagnostics is usually not included in the cost of repairs indicated in the price lists of services.

In most cases, only after diagnostics are carried out, the exact cost of repairs is determined by the service center technician.

What to do if the multicooker breaks down - try to fix it yourself or use the services of a service center, of course, is up to you to decide. We hope this article will help you make the right decision.

Appliance cover

Today we will tell you how to repair the Redmond multicooker. We will try to fix the lid with our own hands.

This is a standard breakdown for most types of multicookers. Damage to this cover is due to planned aging, that is, the manufacturer deliberately makes it unreliable. The finger on the button broke... The lid moved as a result of the temperature... The rods reach special grooves and the lid is inserted, but a few millimeters are missing...

We will need small magnets and will make a magnetic lid that closes, is held on by magnets and is opened under force. You need to glue 4 magnets - two on the lid and on the body of the multicooker itself. The multicooker bowl is pre-removable.

We select the points where we will glue the magnets. Degrease the surface with alcohol. First, apply high-quality glue to selected points on the body and press the magnets. Let's wait until the glue dries. Now, not forgetting to respect the poles of the magnets, glue them to the lid. In this case, it is more convenient to apply glue directly to the magnet. If there is a need and the height of the magnets is insufficient, you need to glue two magnets on top of each other. Here we are already acting empirically.

This, of course, is not the most common way to solve the problem of a broken multicooker lid latch. Basically, experts solve it by replacing the handle, if the mounting points are not damaged, but the handle itself is broken. Or, as an alternative, drill holes in the handle and fix it with screws. The choice is yours.

This is interesting: Why the vacuum cleaner began to work loudly: causes of malfunction, how to repair

Random shutdown

If you load the saucepan more than the required volume, spontaneous shutdown may occur earlier than expected. Otherwise, the cause is an incorrectly set temperature. Although the multicooker is smart, it does not know how to recognize when food is ready. Sometimes even a timely shutdown causes misunderstanding among people, saying how this can be: the multicooker has turned off, but the food is not yet fully prepared. Nothing wrong with that. Just set the extra cooking time and wait. Alternatively, you just need to try preparing another dish in strict accordance with the recipe according to the instructions, and if the food is tasty, then the problem is definitely in improper handling. Well, if the problem happens again, then... you know what to do (service center and all that).

Cleaning the multicooker

To clean the inside of the product yourself, you must first study and strictly follow the algorithm of actions.

• We remove the lid of the multicooker - it is made of metal or plastic (depending on the cost of the product), then unscrew all visible elements that are secured with screws.
• We clean the internal elements from loose substances by turning the multicooker over and shaking it gently but vigorously.
• If no liquid is found inside, then collect everything in reverse order.

When a blockage occurs at the bottom of the device, where the contacts are located, the action algorithm will be as follows:

• disassembly is carried out from below - unscrew the screws securing the bottom cover;
• disconnect the wires going to the software and heating board;
• unscrew the screws securing the heating elements - after this they should be easily removed;
• carefully, so as not to damage, dismantle the internal thermocouple;
• We clean all microcircuits, temperature sensors and boards from bulk products.

If you do everything without haste, carefully and carefully, then you can clean the Polaris or Mulinex multicooker yourself without any problems.

Microcircuits in modern multicookers

Modern multicookers contain 2 microcircuits. The first is located in the very center of the device inside the working cylinder and is responsible for controlling the temperature regime. The second is located at the bottom of the multicooker and is a power electronic board.

If you carefully examine the microcircuit, you can find some types of faults with the naked eye:

• swelling of capacitors;
• damage to solder seams;
• soot formation;
• track detachment;
• darkening of resistors.

The best repair option would be to completely replace the electronic board. However, you can repair the solder joint or trace of the chip by using #0 grit sandpaper and tinning the broken areas. The jumpers are recreated from the legs of burnt resistors. It is advisable to use varnish to fix solder joints and tracks, as it protects the board from leaks and oxidation.

Cleaning the multicooker valves

Problems with pressure in a multicooker can occur due to clogged valves. The operating instructions recommend cleaning the inside of the multicooker lid. We remove it by first unscrewing the central nut and wash the valve rubber, which was mentioned above.

Let's move on to cleaning the second valve. Using pliers or wrenches, unscrew the valve nut, remove the bushing and washer. Turn the lid over and remove the valve. Wash with cleaning agent and wipe the valve elements. We collect it in random order. Just pay attention: it is very important to place the valve rubber correctly, on the right side. We assemble the second valve, not forgetting that its rubber band should be on the outside of the lid. We return the lid to the multicooker, screwing it with a nut.

What breaks most often in a multicooker?

@tehrevizor.ru
The most popular breakdown is considered to be blown fuses. Since people quite often use the appliance incorrectly (choose the wrong cooking mode, do not clean the valve for steam release, etc.).

The second most popular problem is the problem of wire breakage and burning. Sensors and LCD displays fail much less often. It is very rare that the electronic control board breaks down.

The multicooker does not work

In this section we will talk about possible breakdowns when the multicooker does not turn on at all. Option one is the Redmond RMC-PM380 multicooker. When the power is turned on, there is no indication, the buttons do not work.

Let's start repairing the Redmond multicooker with our own hands. Turn the device over and turn off the power. Unscrew the bottom. We begin the inspection with the thermal fuses, which are located inside, in the very heart of the multicooker. Usually they are covered with cambrics and dressed in wires of different colors. We test the fuse contacts with a multimeter. If they do not ring through, they need to be replaced. After replacement, we test the device. The indicator lights up, the multicooker is working. We remind you once again: the thermal fuse needs to be looked at first.

Fuses in Redmond

Why are thermal fuses needed? The reader will immediately interrupt - protect the overheated device. We see reasons to say: thermal fuses are needed to repair Redmond multicookers more often.

How disparate facts are connected. This is what the owner, an experienced multicooker user, writes to members of the forum: “Accidentally turned on the device without a pot, noticed after 40 seconds, immediately turned off the device.” The woman wanted to know what would happen to the Redmond M90 if she didn’t put the pot back in place at all.

Dobrokhot suggested: nothing terrible will happen. The main button (see above), located under the bottom of the pot, will prevent the multicooker from turning on in the absence of dishes. The hostess conducted an experiment: with the lid open (!) and the pot pulled out, she launched the program. Within 10 seconds the heating element became hot. The result is stunning: there is no protection against incorrect switching on in the Redmond multicooker.

What will happen if you leave the cook unattended as a kitchen assistant for a long period of time. The conclusion is suggested by an advanced forum member: to protect against overheating, there are thermal fuses inside. Security elements cope with their function only once - when they burn out. After an incident, the intervention of a “specialist” will be required.

Actually, for this purpose we are considering the manual repair of Redmond multicookers - when the reason is known, the repair becomes a simple matter. If a multicooker once left unattended refuses to turn on, the problem is probably the thermal fuses.

Now let’s read the service book issued to the buyer of the Redmond multicooker. Quotes are selective so as not to bore the reader with too much information. Warranty repairs are not carried out if “the product has... thermal or other damage caused by improper operation...”.

Redmond multicooker, warranty repair - are the two things compatible? Not if you have developed a habit of leaving the device on unattended! The main button under the pot is present to measure the temperature and maintain the correct cooking modes.

In this regard, I would like to remember users who, having forgotten to install the pot, pour liquid inside and pour out cereals. Be extremely careful. If something irreparable happens, immediately unplug the cord from the 230 V socket. The device must be cleaned. The following information was found: it is possible to simply rinse with water, dry the microcircuits for 1 week at room temperature... Naturally, you can use the method at your own peril and risk. The official instruction manual does not provide for anything like this.

Changing thermal fuses

One or more thermal fuses are always located in the middle of the product, no matter what manufacturer the multicooker is, for example, from Panasonic. They are covered with cambrics, which in individual products are assembled into a common clamp, but most often they are not fixed.

Under the bowl in the multicooker there is a special unit, visually similar to a metal mushroom, which is supported by a spring from below: various fuses are located around it, you can get to them and fix them only by unscrewing the fastenings of the bottom cover.

When replacing a thermal fuse, only clamps are used: they cannot be soldered, because they are very sensitive to any increase in temperature. You can check the condition of the fuses using a tester to find out which one has blown.

Another temperature sensor is located in the lid; you can check it without opening the plastic device again: just measure its resistance while heating the lid. If there is no change in resistance, then you will have to disassemble and carry out unscheduled repairs of the multicooker lid and replace the part.

Every user should know that thermal fuses cannot be repaired; their specific purpose is to burn out when there is a sharp rise in temperature.

Premature shutdown

When asked by users why the multicooker turns off ahead of time, experts give only one answer - improper use of the product, expressed in excessive loading of products, or the wrong cooking mode was set with an incorrect temperature.

These household appliances are distinguished by the presence of an intelligent processor that monitors the precise execution of the cooking mode, but the system is not able to recognize whether you have placed the food correctly. It may react to an insufficient amount of liquid, causing the mass to burn to the walls of the bowl.

When the bowl gets very hot, the temperature sensor is triggered, the heating elements stop heating, the cooking process stops, and the product displays an error code . Disconnection can occur for several reasons:

• a manufacturing defect that did not show itself during inspection before purchase - most likely it is a temperature sensor, you need to take the product to a service center;
• mechanical damage to the bowl during transportation - carefully inspect everything when purchasing, because the device may turn off due to an external defect;
• each mode has its own temperature - if its upper limits are exceeded, automatic shutdown occurs, since the built-in overheating protection is triggered;
• strictly measure the amount of ingredients using a measuring cup; if there is an excess of food, the machine may turn off automatically;
• take out the bowl and inspect the space under it - maybe loose ingredients or moisture have got there;
• the pressure control valve is clogged - wash it;
• If the contents in the bowl burn, the system stops the cooking process;
• The bowl is full of solids and no water has been added.

Users immediately blame the manufacturer for any failure, but in most cases the breakdown is your fault: due to inattention or hasty loading, many housewives do not close the lid tightly. Therefore, you should not immediately go to the service center, you need to analyze the situation, try cooking a simple dish - it is possible that the reason for the failure of the multicooker is hidden in improper handling of it.

Control board repair

We have already explained how to remove the back cover earlier - you need to unscrew the fastening screws, then disconnect the thin wires that connect the control board to the power supply. Next, we disconnect the heating elements and, with special care, the thermocouple located in the center - this part is very fragile and is afraid of any mechanical impact.

To clean the board from carbon deposits, it must be disconnected, providing access from both sides. We carefully inspect it for the presence of grease stains; if there are any, wipe it with a cotton swab dipped in alcohol. For multicookers of different models, the arrangement of the boards may be different.

Microcircuits must be examined very carefully, using a magnifying glass, to identify areas of carbon deposits, violations of tracks and solder seams. If you don’t understand anything about this, then you shouldn’t contribute to causing defects on such a fragile and important part. Damaged parts are carefully desoldered and replaced with new ones, taking into account the matching markings. After repairing the boards of the Redmond multicooker, if you did it yourself, you need to varnish all the tracks to protect them from moisture penetration.

Failure Diagnosis

Before troubleshooting these household appliances, the user needs to know that all the main programs of home assistants (multi-cookers and steamers) are considered a trade secret of each manufacturer and are not subject to publicity. Why the multicooker does not work - not a single specialist from the service center will immediately answer this question, because the entire operation of a household appliance is based on the clear interaction of two sensors. Some craftsmen believe that inside the electronic board the developers have stored a memory of the nominal temperature, duration of operations, as well as specified programs. Based on this data, the heating elements in the Redmond multicooker are programmed.

The product has sensors installed.

1. The thermistor is inserted into the main button of the product. It is very difficult to dismantle it, because manufacturing companies do everything to make independent repairs difficult, considering this the prerogative of special service centers. It is the Redmond company that fills all terminals with a compound - a special insulating material, making their dismantling impossible.
2. The second working sensor is inserted inside the cover of the product - to get to it you will have to dismantle its filling with compound, disconnect the sensor and try to turn on the product. If it doesn't work, then you are on the right track. For 100% results, test the wires going to the sensor using a multimeter.

For the multicooker to operate effectively, it is necessary to read readings from both sensors at once: they transmit the signal through wires to a special terminal on the control board, which is located under the panel with buttons. When the multicooker does not work when turned on, the culprit may be the power supply - you can check this by plugging the product into the mains. If at least one of the indicators is illuminated from the inside, then everything is fine. In other cases, you will have to contact specialists.

There are times when the product is not included in the cooking process - the bowl cannot heat up to the required temperature. Try measuring the resistance on the transformer. Behind it is a rectifier consisting of 4 diodes. The main board is positioned with all elements down, so if the current increases, the solder will melt and flow down to the bottom of the product. When opening the bottom cover, this can be determined visually by drops of tin - this means that a short circuit has occurred inside and the heating elements have turned off.

Sometimes it is worth checking the functionality of the relay. Connect the product to the network, turn on any program. If you hear a characteristic click, then the relay is working, otherwise you need to make a step-by-step replacement: first the relay, and then the control board.

Problematic latches

Quite often, multicookers and steamers from the Redmond company have top lid latches that break. According to experts, this is one of the most common breakdowns. Some craftsmen claim that this is a defect introduced by the manufacturer, so that users buy new top covers after a certain period of use of the product.

Advice! Close the top lid of the Redmond multicooker with the latch already pressed and release it only after the lid fits tightly. Thus, the load will be much less.

If a breakdown does occur, then you shouldn’t immediately go to the store and spend money on buying a new lid, especially since with such a minor breakdown it’s pointless to go to the service center: they simply won’t undertake to repair the multicooker, advising you to install a new lid. There is an original method of repair at home that does not take much time and effort; you just need concentration, patience and the ability to work with superglue. In order to properly troubleshoot the problem, carefully watch this video:

The principle of operation of a home multicooker

Unique home multicooker programs are corporate secrets. The controller is protected against reading information, excluding copying by competitors. The algorithms are stored in non-volatile memory. It is known: there are two sensors that allow the technician to create an algorithm for further actions. The multicooker design is based on mathematical calculations. We believe that the temperatures and durations of individual sections of the recipe are stored inside the memory chip. Valuable information lays the basis for controlling the heating element. The multicooker contains two sensors:

1. A thermistor is attached to the back of the main button. It is sometimes difficult to remove; the manufacturer did not at all intend the intervention of a self-taught person, bypassing warranty services. A considerable surprise awaits the lucky owners of Redmond: the removable terminals are filled with a compound, non-invasive dismantling is impossible. The news will prevent you from repairing the multicooker yourself.
2. Another sensor is hidden inside the lid. It is extremely difficult to get there; you should only go there if you are completely sure that the fault concerns the sensor. How to gain ironclad confidence. Try to unplug the desired connector, regardless of the compound, and then turn on the home multicooker. Is it still the same? There is a high probability that the snag has been found. Gain confidence by measuring the resistance between the sensor wires and heat the cap. Redmond multicookers pass the wires through the loop of the removable lid. After unscrewing the screw, dismantle the shield, pull the wiring out, cook with a home multicooker, while simultaneously measuring the resistance. You don't have to look for third-party funds.

A home multicooker requires readings from two sensors to operate. A pair of wires come from the sensors to the terminals of the control board; the substrate is often located under the buttons. Determining a faulty power supply is extremely simple: there is no lighting of the display panel elements in any state. Probably a source failure. Remove the bottom, measure the output voltage of the switching power supply. Do not confuse this with a transformer. Remove after filters and diode bridges.

Touch or mechanical control. In the latter case, the printed circuit board is equipped with microswitches. Counters count the number of presses, and the memory chip selects the appropriate information to execute the program. Traditionally, a pair of power wires come here, one goes out (the control signal of the relay that powers the heating element). Really simple! One signal runs the kitchen in a home multicooker. Getting the information requires a chipset to sweat. The signal is a constant level that turns the transistor on and off. The zener diode prevents the contact voltage from exceeding the limit level. The relay armature closes the heating element circuit. Now let's look at the processes occurring in a switching power supply.

Common causes of failure of Redmond multicookers

Most malfunctions occur due to contamination of the device contacts. This can be caused by liquid or bulk products entering the inside of the device, such as:

• cereals (rice, buckwheat);
• sugar;
• salt.

This type of breakdown is the most harmless and will be easy to repair multicookers with your own hands. It is worth remembering that until the process of cleaning and assembling the structure is completed, the device must under no circumstances be plugged into the network.

Advice:

Operating requirements

To protect the Redmond multicooker from breakdowns and not to think about how to fix it yourself, you must follow the requirements specified in the device instructions.

The first step is to highlight the sequence of placing food before preparing the dish. Before placing the food bowl, you must remove it from the Redmond multicooker. Otherwise:

• liquids poured into the bowl may accidentally spill inside the mechanism;
• forgetting that the container is on the table, you can start pouring liquid into the equipment, thereby drowning the mechanisms or covering them with bulk products.

See also -
What to do if the multicooker does not turn on?

How to clean a Redmond multicooker?

To clean the device yourself, it is important to study and follow the sequence of actions.

• Remove the metal (plastic) cover, as well as other visible elements attached with screws.
• Clean the chips by turning the device over and gently shaking it off.
• Secure the lid and other upper elements.

If the clogged contacts are located at the bottom of the device, you must:

• unscrew the screws securing the bottom cover;
• disconnect the cables connecting the heating and software boards;
• remove the heating element by unscrewing the screws;
• carefully remove the internal thermometer without damaging the device;
• clean chips and boards from loose products.

If you follow the disassembly rules, cleaning the device will not cause much trouble.

See also -

Choosing an inexpensive but high-quality multicooker for the home

The most common malfunctions of multicookers and system errors

If the multicooker breaks down and does not work, then in some cases the corresponding error codes are displayed on its display, by which you can understand what exactly happened.

If you do not understand the design of a multicooker, then in the event of a breakdown it is better to turn to professionals

The Redmond multicooker is characterized by the following designations:

• E1 or E2 – system error, possible breakdown of the power supply, heating element, or the lid is not tightly closed;
• E3, E4 or E5 - the temperature sensor or fuse has failed, the system may have turned on to prevent overheating.

Also, codes E1, E2, E3 may indicate that moisture has entered the mechanism. In this case, you need to unplug the device and give it time to dry.

Also, one of the most common breakdowns of multicookers is contamination of the device. This happens when liquid or any bulk substances, such as rice or sugar, get inside the mechanism.

To solve the problem, the device needs to be cleaned by performing the following steps:

• Remove the top cover of the device by unscrewing the bolts;
• Clean the circuits by turning the device over and shaking it gently;
• If the blockage is at the bottom, then you need to remove the bottom cover;
• Disconnect the contacts of the software and heating boards;
• Remove heating elements, temperature sensor and other elements;
• Clean all parts from crumbs or other contaminants.

If the thermal relay becomes clogged, the contacts should be slightly unclenched and then wiped with thick paper. This can happen if water gets into the device or condensation forms.

Multicooker software errors

Usually, if the multicooker suddenly breaks down or refuses to turn on, a code appears on the display that indicates the cause of the failure. Typically, the cipher begins with the letter E and a number from 0 to 5 after it. The code indicates the possible cause of the malfunction, so further repair actions depend on this index.

The following message options are possible:

• E1. This means that the heating element has burned out; this happens when moisture, fat, or food particles get inside. You will have to disassemble the structure, clean it and dry it.
• E2. On Polaris models, this means a short circuit in the upper temperature sensor, which is mounted under the cover. In addition, this combination may indicate an open circuit, so you need to check the wire that goes from the display to the sensor. To assess its condition, you need to use an ohmmeter.
• E3. First of all, you need to check the tightness of the lid. It is also possible that the cause of the malfunction lies in the dirty inner surface of the case. It is necessary to disassemble the product, clean it and dry it.
• E4. The pressure sensor is broken. Most likely, the problem is that it is clogged, but a broken circuit is also possible. In addition, this error occurs when there is a malfunction in the microprocessor. This is the worst failure code, since you will have to check virtually the entire product.
• E5. The index is displayed when the overheating protection system is triggered. Perhaps you simply placed the device next to a radiator or a gas stove that was on. But the problem may also be hidden in clogged steam valves. If the appliance smells like smoke, then you have probably burnt the wiring.

When can you not do anything?

In the following cases, repairing a multicooker at home with your own hands is unacceptable. You need to take it to a specialized workshop:

• no reaction to actions;
• no temperature information;
• a different error code appears on the display;
• there is visible damage to the cable or housing;
• programming does not work;
• the multicooker does not heat;
• The lid is not sealed.

What problems can be fixed?

If E1 or E2 messages are detected, you must perform the following actions:

• Check the surface underneath the bowl. If there are drops of moisture or food crumbs, clean and dry the product.
• If everything is clean inside, then you need to turn the multicooker over and unscrew the fastener that holds the bottom cover. In this way you can disassemble the structure. Inspect all the insides; if there is dirt or moisture, remove it.
• If everything is clean inside, then you need to find a thermocouple - this is a tubular sensor with a connected wire. To clean, you will need fine-grit sandpaper (no. 0) folded in half. To disconnect the contacts, you need to press the top plate from the side of the adjusting screw so that you hear a click. After this, you need to insert the sandpaper and release the plate (let the contacts go back in). Then you need to carefully clean the terminals.

The easiest way is with error E3. To fix the problem, you need to turn the Vitek multicooker over and unscrew the fastener that holds the bottom cover. Then you need to take out all the insides, clean them and dry them. For quick drying, you can use a hairdryer, but with the setting on low intensity. Then assemble the structure.

The most difficult problem will be with error E4. To fix it, you will need to check all temperature and pressure sensors, inspect surfaces for dirt and moisture. Careful cleaning with sandpaper will be required. If you have some experience, you can try to do everything yourself, but it is better to take the device to a service center.

With error E5, overheating occurred in the Moulinex multicooker. If a problem is detected, you must immediately press the “stop” button (turn off) and also unplug the power cord from the network. Then you should open the lid and let the multicooker cool, you need to wait at least 20 minutes. At the end, it will be useful to assess the condition of the internal surfaces for contamination.

Switching power supply for a home multicooker

The transformer is clearly shown in the figure. Carefully wrapped with electrical tape and filled with transparent compound. On the right is the input filter. Preventive measures help protect the device from input pulsations (a home multicooker does not create voltage fluctuations). On the board turned upside down, you can see: a resistor plus a capacitor is on the way to the transformer, protecting the low-voltage part. The heating element is powered in a separate way.

An interesting feature of the above diagram. The transformer carries two secondary windings connected in parallel. We believe that this exotic step increases the reliability of the device, since large consumption is not planned on the horizon (energy is spent on heating elements), the element base was created to serve as the basis for the construction of other (household) appliances, the multicooker went along with other factory jewelry.

Ringing a transformer is extremely simple. In the off state, the relay is open; it is unnecessary to disassemble the home multicooker. There is a fairly low resistance between the input terminals of the plug. There is a nuance, the photo shows: there is an electric filter in parallel. To understand whether the winding is faulty, you will have to find out the value of the resistor. When connected in parallel, the sum of ohms is less than the smaller resistance. The winding has a small rating, a maximum of two digits. The capacitor is unusual, if it breaks, the device will continue to work, only the protection will be reduced. The check is simple. Charge the input circuit of the home multicooker with direct current, and place a voltmeter in parallel with the battery. Did the signal disappear immediately or fade out? It must be the latter.

After the transformer there is a full-wave rectifier formed by four diodes. Even a schoolchild can ring the bell.

We remind you: the diode conducts the direct current of the multimeter in only one direction. In a similar way, the integrity of pn junctions of bipolar transistors is checked in a simplified manner. An arrow in an electrical circuit indicates the direction of flow of positive charges (not electrons). Avoid confusion.

Following the rectifier, the switching power supply circuit of a home multicooker includes another filter containing a resistor of the largest dimensions and a nearby capacitor. Then we see an emitter follower with a small zener diode and a resistor that selects the operating point. The proactive step matches the circuit to the load. Attentive readers will notice: the blue and red wires supply power to the home multicooker. White controls the resistor that energizes the relay gate. It is easy to trace: the signal approaches the base (middle contact), at the right moment the voltage generated by the rectifier and filter switches to the relay of the home multicooker. A zener diode is connected in parallel, since (we assume) the rectified voltage has a different rating: the power supply to the microcircuits and the relay is supplied at a different voltage.

We see the disadvantage of the circuit: part of the power is lost, the on state is dominant during cooking. As soon as the control signal disappears, the transistor breaks the connection, the relay opens, and the heating element stops heating. It seems that, using the information, readers will easily repair the multicooker with their own hands, simply by poking where they should be with the probes of the multimeter.

Please note that there is a piece of double wire in the place where the schematic outline of a fuse can be seen in the photo of a home multicooker. Passing the indicated place, a current of 230 V is supplied to the relay. We believe that the jumper replaces a fuse that protects the local network from excesses. In the working position, the printed circuit board is located elements down. As soon as the current exceeds the permissible limit, the wire will begin to melt, the metal will simply flow to the bottom of the home multi-cooker (nothing can cover up such an incident). If during dismantling the indicated sign is visible, a short circuit has occurred inside. The heating element of the home multicooker is broken, or the reason is different. Take some time to restore the jumper.

Take a multimeter and call the heating element. One end will open the relay. Resistance is found from Ohm's law. It is necessary to obtain the power of the spiral of a home multicooker for 230 V, then we will calculate the resistance. First, the square of the effective voltage value (230 V) is divided by the power (watts). The result will be 30 Ohms, the calculated numbers will be shown by the multimeter. It’s easy to check the relay if you turn on the installed program. A voltage of 230 V will immediately appear on the heating element after a slight click. If there is no effect, it is time to change the relay, or the control circuit is broken. The latter is easy to check: control voltage will arrive at the base of the transistor (middle terminal) via the white conductor. Finally, the output parameters of a switching power supply can be easily measured.

It remains to add: detachable connections are often filled with compound, and it is quite difficult to disassemble the soldering. The designs are typical, the authors are 100% sure: repairs of Polaris multicookers are carried out according to the standard scheme, just like the Cuckoo multicookers. The main thing in the process is to maintain the presentation of the equipment. Each manufacturer strives to complement the design with new decorations and complicate the task for the repairman. The sophisticated marketing policy is understandable: companies want to know whether the self-taught person looked inside the acquisition before taking it to the service center. Repairing a Mulinex multicooker will certainly not go unnoticed by specialists.

For a similar purpose, the process of disassembling the product body becomes more complicated. The screws are selected non-standard. They are often screwed on “for show” and do not hold anything. An inexperienced technician will certainly leave marks, voiding the warranty of a scratched device. The further development of events is obvious: increased fees, refusal to service the damaged product.

What is the function of a thermal fuse?

The thermal fuse for a multicooker is one of its most important parts. It is a small piece of wire, indistinguishable from a resistor. The conductivity indicator is 10-15 A, based on the type of element. The highest temperature is 150-170 degrees. Exceeding the permissible limits will lead to the fuse burning and breaking the electrical circuit, which can be determined using a multimeter.

Operating principle and main structural elements:

The bowl sits directly on a heating element, which creates temperature from an electric current. Multicookers make little noise during operation. At the same time, due to the tightness, increased pressure is created inside, which can be regulated using a special valve for steam. There is a plastic sieve over the bowl, on which it is permissible to stew meat and vegetables. You can not only select the temperature, but also set it to automatically change during the cooking process.

The most common operating principle is heating the bowl from an electromagnetic coil. This method has high efficiency, and the design itself is reliable. A more modern heating system is that it is not the heating element that heats up, but the multicooker bowl itself. This happens under the influence of electromagnetic waves. Because of this, the multicooker bowl looks more massive in order to better retain heat.

Finding and replacing the thermal fuse

Most multicookers have several thermal fuses, which are covered with plastic to protect them from moisture. All of them are located inside the case, so to find the burnt element you will need to disassemble the device. To do this, you need to turn the multicooker over, find the fastener from below that holds the bottom cover, and unscrew it.

After the device is disassembled, you can see several wires inside; you need to find the one that goes from the electrical connector to the terminal of the heating element. The wire will go through a thermal fuse, which is located in a plastic thermal insulation tube.

In most cases, unsecured thermal fuses simply hang down, but sometimes they are fixed with clamps that are attached to a screw. Please note that fuses are very sensitive to heating, so soldering is prohibited.

In addition, manufacturers fix them using a crimping method, so the thermal fuses cannot be removed. Therefore, to determine the condition of each element, it is necessary, without removing them, to use a multimeter to determine the resistance level. Once the condition of each fuse is determined, the faulty parts must be replaced.

Replacing a thermal fuse using an example

Let's look at replacing one thermal fuse using a live example. There is a multicooker whose display does not turn on, initially we do not know what the problem is.

Let's disassemble the device. To do this, you need to unscrew one screw from the bottom and open the bottom cover. You can see that the design of the multicooker is extremely simple. Its insides can be divided into 3 parts:

• The power unit is a power supply and a relay switching heating element.
• Control board with display (which does not work).
• A heating element.

Let's look at the power part of the multicooker and its wires:

• The white wire from the network connector goes to the power supply.
• The red wire goes from the power connector through the thermal fuse to the heating element terminal.
• The black wire goes from the heating element terminal to the power supply.
• The red wire goes from the second terminal of the heating element to the power supply to the switching relay.
• Yellow is the common ground wire that connects the metal structures of the multicooker (external and internal casing).
• The white wire goes to the control board from the switching relay.

The figure shows wires by numbers

First you need to find out if the electricity is reaching the power supply. To do this, you need to connect the multicooker to the network and first measure the voltage at the terminals of the network connector itself.

Next, check the voltage between the connector terminal and the heating element terminal. We see that electricity does not reach the heating element through the red wire.

The red wire goes through the thermal fuse, most likely that is the problem. Let's take it off. To do this, you need to unscrew the screw from the metal plate with which the thermal fuse is attached to the multicooker body.

Unscrew the screw.

Let's look at the model:

• model – RY184;
• temperature – 184
  O

  WITH;

• current – ​​10 A;
• voltage – 250 Volts.

Thermal fuse close-up

Disconnect the thermal fuse using wire cutters. We order a new element with similar characteristics.

The thermal fuse cannot be connected to the wires by soldering, so you need to make sleeves for crimping. They can be made from a radiator for a transistor. The resulting two plates need to be cleaned with sandpaper. And then bend them into open tubes.

Sleeves that came from the radiator

Using sleeves, we attach the thermal fuse to the wire by pressing it with pliers.

The fuse is fixed to the inner housing using a metal plate in which it is wrapped. It needs to be screwed back to its original place. After this, you can check the voltage at the terminals.

When we are convinced that everything worked out, turn on the multicooker and see the result.

Design and principle of operation of a multicooker

To successfully repair a multicooker with your own hands, you need to understand the device and the principle of its operation. The easiest way to understand this issue is to have a diagram of the multicooker device in front of your eyes.

In appearance, the multicooker resembles an ordinary saucepan, on the side of which there is a display and buttons for selecting the cooking mode. In its lower part there is a connector for connecting the network cable to the power supply and a switch. On top of the pan there is a hinged, hermetically sealed lid with a latch. If you press the button to open the lid, you will find a loose cooking bowl inside. The bowl resembles a saucepan without handles and is easy to remove.

The heating and operating mode control system of the multicooker is located in its lower part and is covered with a plastic lid, which is also the bottom of the multicooker. The heating system of a multicooker differs from the heating system of an electric kettle or iron only in the presence of a microprocessor control system for its operating mode.

Electrical circuit and device

The operating principle of multicookers of all models and manufacturers differs slightly, so after studying the design and operating principle of the REDMOND RMC-M23 multicooker, you will be able to successfully repair any other.

The 220 V supply voltage is supplied to the three-pin standard connector of the multicooker, located in its lower part. One of the connector pins is grounding, designated PE

, and
a yellow-green
wire is connected using a threaded connection to a metal housing.
The yellow-green
wire is also connected to the metal part of the multicooker lid.

Wiring diagram

Power supply to the multicooker is supplied using the wires indicated in the diagram L

and
N.
_ In the wire circuit L (red in the photo), a switch and a thermal fuse are installed in series. The switch is used to turn on, and the thermal fuse is used to protect against overheating.

From the thermal fuse, the supply voltage is supplied to one of the terminals of the heating element and the board of the Power and Switching Unit. Wire N (white in the photo) is connected to the Power and Switching Unit directly. The supply voltage from it to the second terminal of the heating element occurs when the contacts of the relay located on the board of the Power and Control Unit are closed.

Power supply and switching

One of the most loaded and often fails is the Power and Switching Unit. This block performs two tasks at once. Converts 220 V AC voltage supplied from the network into 5 V DC voltage (to power the control unit) and 12 V (to power the switching circuit), and provides, upon a signal from the Control Unit, the supply of 220 V supply voltage using a relay (black rectangular part ) on the heating element.

As you can see from the photo, some elements are missing on the board; it is obvious that the board is universal and only the elements necessary for the operation of the multicooker model REDMOND RMC-M23 were installed on it. Additional elements are installed if the board is used in other REDMOND models.

At the bottom left of the board you can see a metal disk covered in yellow insulation. This is a disk power supply (battery) of type CR2032 with a voltage of 3 V. The battery is designed to store cooking programs manually recorded by the cook in the memory chip of the multicooker control unit after disconnecting it from the network.

Control block

The brain of the multicooker is the Control Unit. Thanks to this unit, the multicooker, in comparison with the electric stove, began to meet all the modern requirements of kitchen masters.

The photo shows the control unit of the REDMOND RMC-M23 multicooker from the installation side of the elements. A dark square with pins on all four sides is the processor. On the other side of the board there are: a display, LEDs for menu illumination and operating mode control buttons.

The control unit is connected to the rest of the multicooker circuit using three connectors. Wires from the six-pin connector go to the Power and Switching Unit, and from two connectors with two contacts each go to two thermal resistors. White wires are connected to the thermal resistance, which is installed at the bottom of the pan, and blue wires are connected to the thermal resistance, which is located in the lid.

What task do thermal resistances perform in a multicooker?

Unlike constant resistances, thermal resistances (thermal resistors) greatly change their resistance when the ambient temperature changes. Thanks to this property, thermistors are widely used in household and industrial appliances as sensors for automatically adjusting and maintaining a given temperature.

The photo shows thermistors of type MF58 50 kOhm 1%, which are installed in the REDMOND RMC-M23. The MF58 thermistor is universal and is used to regulate temperature in many household appliances.

There are two thermistors installed in the multicooker, one is secured with adhesive aluminum tape on the metal part of the lid (pictured above), and the second is secured inside a spring-loaded glass at the bottom of the container (photo below).

After selecting the operating mode and pressing the “Start” button, the supply voltage is supplied to the heating element. After heating the lower thermal resistance (the bottom of the bowl in which the products are placed) to a certain temperature, the supply of voltage to the heating element is stopped until the temperature in the upper zone of the multicooker’s working capacity reaches a certain value. Then the heating turns on again and after a while turns off again. The frequency and duration of turning on the heating element depend on the selected mode and the volume of the bowl.

Thus, thanks to the presence of two thermistors, the microprocessor of the Control Unit constantly receives data on the heating temperature of the lower and upper zones of the bowl, which allows you to regulate the heating rate of products and maintain the required cooking temperature.

Why install a thermal fuse?

The thermal fuse is not directly involved in the operation of the multicooker and serves only to protect it from overheating in the event of a failure of the control system or a gross violation of the operating rules. If the temperature at the installation site of the thermal fuse reaches 170°C, it will trip and break the circuit. The multicooker will be de-energized and heating will stop. Blowing the thermal fuse is equivalent to turning off the switch.

Usually, in the electrical circuit of a multicooker of any model, a thermal fuse is installed, which you see in the photo. If it fails, the multicooker will have to be repaired. To do this, simply remove the bottom cover and replace the thermal fuse with a new one. But we must take into account that it is likely that the thermal fuse could have tripped due to a malfunction of the Control Unit or the Power and Switching Unit. Therefore, before replacing the thermal fuse, you must ensure that they are in good working order.

Attention! When repairing a multicooker and any other household electrical appliances connected to the household network, care should be taken. Touching exposed parts of a circuit connected to an electrical outlet may result in electric shock. Don't forget to unplug the multicooker from the socket! Just turning off the multicooker with the switch is not enough!

Durability of multicookers

You can find out the service life of the multicooker from the instructions. For example, the well-known Redmond provides an extended warranty of 25 months, and data from the technical data sheet says that the device will work for 5 years.

Russian legislation dictates that warranty service must be at least a year; if the manufacturer independently increases the period, it means that it is confident in the quality of its products.

The multicooker itself, from a technical point of view, is a simple device. Malfunctions in the first days may be the result of a manufacturing defect, and if a breakdown occurs after a year or two, then the reason lies in the natural wear and tear of some parts, or it is the result of improper use.

The reliability of any household appliance is ensured by two factors: proper maintenance and adherence to operating rules. They should not be neglected, even if it is not initially clear why the manufacturer indicated certain requirements.

What is the button at the bottom? CONTENTS

1. The “button” at the bottom of the tank turned out to be not a switch button at all, as it seems (so that the multicooker would turn on only when a pan was installed inside the tank), but simply a block pressed tightly to the pan with a temperature sensor and a thermal fuse inside.

Photo 5. “Button” - a block with a temperature sensor and a thermal fuse

The red wire here is the network wire, from 220 volts, first it passes from the socket through the thermal fuse in this button (the official name is “thermal fuse 165°C 10A”; when burned, it cuts off the power from the network), then it is connected to one of the terminals of the disk heating element and only then goes into the power supply board. Yellow thin wires go to the temperature sensor (it is an NTC thermistor with a resistance of 50 KOhm at 25°C).

Tips for users

Multicookers of any brand may develop various malfunctions during operation, but this does not mean that the equipment is unreliable. There are specific reasons why cooked food in a bowl may burn slightly:

• factory defect of the container;
• incorrect loading - the required amount of water was not added.

If any equipment failure occurs or attempts are made to switch off from the cooking process, you must deal with it thoroughly - first check everything step by step, starting with adding the ingredients and check the detailed description of this process in the instructions. If you find a burnt contact on a sensor or heating element, you do not need to call a technician - this operation is very simple and can be done by any user, even those with a liberal arts education.

According to experts, the main failures of reliable household appliances occur due to the fault of the user - your negligence or inattention. Remember that if the device does not turn on, does not turn off, or does not start the set cooking mode, then immediately unplug the multicooker from the mains.

All models can diagnose problems and display error codes on the display - a list of their explanations is in the description. Study it carefully before attempting any repairs yourself.

Other causes of multicooker malfunction

Less common causes of device malfunctions and shutdowns include:

1. Wrong choice of cooking program. Each dish has a specific program; if it is set incorrectly, there will be no result.
2. Clogging of the special valve designed to release steam. Steam accumulating inside can overheat the device.
3. The deformation of the bowl is, for the most part, a manufacturing defect. Repairs are usually carried out under a warranty card.
4. Malfunction of the temperature sensor, which affects the actual temperature readings. Transmitted incorrectly, they can cause the bowl to overheat and turn off the time countdown.
5. Premature shutdown, often due to overloading the bowl, insufficient liquid or setting the wrong cooking mode.
6. When the bowl overheats, the triggered temperature sensor gives a signal to the heating element, heating stops, cooking stops, and an error code appears on the display.

Often, for some reason, the multicooker turns off before the programmed time, the heating process is interrupted, and the device turns off ahead of time. It happens:

• if moisture or bulk products get into the heating element;
• when the cooking temperature for a particular product is incorrectly set;
• in case of burning at the bottom of the bowl;
• clogging of the pressure valve, which is located in the lid of the device;
• due to a manufacturing defect in the temperature sensor;
• if the bowl is deformed and the food being cooked comes into contact with the heating element.