The microwave works, but does not heat: what is the reason, how to fix breakdowns with your own hands

Troubleshooting

When the microwave turns on, but for some reason does not heat the food, this may be due to malfunctions in the high-voltage circuit or magnetron. But before checking these elements, you must carefully inspect the working chamber itself. It should not contain any dirt, burnt holes, worn out enamel. In the left wall of the chamber there is a special window closed by a plate made of a transparent dielectric. This plate must be removed and examined carefully.

First, the plate should be cleaned of contamination with alcohol, and then make sure that there are no through-burn holes or darkening from the effects of electrical discharges on it. Otherwise, the plate must be replaced. In addition, such defects indicate that the microwave was started without load or with metal objects inside the chamber.

The magnetron is one of the basic elements of a microwave oven. It is a very powerful lamp that generates electromagnetic waves of a certain frequency. There are a number of very important elements in the high voltage circuit of a magnetron. This is a transformer, a high-voltage diode and a capacitor, a safety diode, which burns out in the event of an abnormal situation.

The safety diode is located near the transformer in a special container.

Its condition can be easily recognized by its appearance. The burnt-out element must be replaced with exactly the same one with similar indicators.

The high voltage transformer is checked only with the load disconnected and the primary winding. To disconnect the transformer, it is necessary to remove the terminals with pliers. The primary winding should have a resistance of about 1.5 ohms, the secondary 110-120 ohms, and the secondary heating coil less than 0.1 ohms. If none of the windings rings, then the transformer must be replaced.

The magnetron is connected to the transformer using a connector. After disconnecting the terminal, check the resistance between the body and the terminals. If there is no resistance, then this means that the feed-through capacitors in the filter are punctured. In this case, either the capacitors or the filter itself must be changed.

By removing the magnetron from its original place, you can check the condition of the antenna cap. If the cap is damaged, it should be replaced. At the same time, you can check the condition of the magnetron insulator. If there are breakdowns in the case or in the antenna, they must be replaced, but if the microwave has been in operation for a long time, this may be economically unprofitable.

If the microwave oven still does not work after all the measures taken, then the locking system should be checked. First, check the tightness of the oven door and the reliability of its locking. To do this, use a sheet of writing paper. With the door closed, a sheet of paper should be pressed along its entire perimeter so that it cannot be pulled out.

If, with the door closed, a sheet of paper can be slipped under it, then the door requires adjustment. Adjustment is made from the side of the lock and hinges. It is necessary to achieve a snug and complete fit. Otherwise, the microwave radiation will go beyond the working chamber.

It is also necessary to check the microswitches. They are called by the tester in the closed and open states. If at least one fails, all must be replaced, since they all have approximately the same wear. If, when checking the high-voltage part and the power circuit of the microwave oven, no malfunctions are found, the control unit should be diagnosed.

The reason for the breakdown of the microwave

The device of the MVP from different manufacturers is practically the same. Korean LG ("Algy"), Samsung ("Samsung"), Daewoo ("Daewoo"), Japanese Panasonic ("Panasonic"), Supra ("Supra"), Sharp ("Sharp") or the British brand Scarlett ("Scarlet ") Have a similar device. They differ only in small nuances: design, color, control panel, number of bolts. Therefore, our article is suitable for diagnostics and repair of any microwave oven. The food in the oven is heated by electromagnetic radiation, which is generated by a magnetron. Therefore, it is logical to assume that if the stove does not heat, he is the culprit. But since the work of a magnetron depends on many other parts and systems, you will have to check them too.

The microwave has stopped heating or is heating for a long time - what's the problem?

1. The mains voltage is less than 220 W. A slight voltage drop may not be noticeable from the outside. The device, as usual, rotates the tray, shines, but does not heat up well or does not heat the food at all. If your assistant heats up every other time, the reason may lie in unstable tension. Check the voltage at the outlet with a tester.

A reading below 220 W indicates an unbalanced, overloaded network or poor-quality transmission line; problems at the substation are also possible. Unloading the network will eliminate this problem - do not turn on many powerful devices at the same time. Install an uninterruptible power supply. If the measures taken did not help stabilize the voltage - contact your electricity supplier: the problem may be a damaged power line.

1. Defective magnetron.

A breakdown of the magnetron is evidenced by sounds atypical for MEP. The device makes noise, hums, hums louder than usual, but does not heat well or does not perform a heating function at all. Check the inside walls of the oven - carbon deposits are a sign that this part has broken. A broken magnetron cannot be called by a multimeter; it can be replaced by carefully observing safety rules.

1. The door interlock is broken.

If there is no blocking, the heating process will not start. So the developers made sure that the microwaves did not harm you through the open door of the device. If the oven does not work, check the shutter and door hinges. This minor damage can be easily repaired by replacement.

1. Blown fuses (or one of them).

If the microwave warms up worse, but the pan is spinning, check the fuses. To get to the fuse, you will have to disassemble the case. A burned-out one differs from a serviceable one by the presence of carbon deposits on a glass cone, a broken spring.

1. A capacitor, a diode is out of order. If the capacitor breaks down, the microwave beeps, heats up weakly, the ohmmeter needle remains motionless when it rings. A breakdown of the diode causes an increased buzzing in the process, the stove heats up weakly. The capacitor, the diode must be replaced, in some cases, repaired (for experienced craftsmen).
2. The control panel is broken.

It happens that the buttons "stick", the contacts come off, the microwave does not turn on. Try to disassemble the control panel, check contacts, clean the keyboard.

Some of these breakdowns are easy to fix on your own; in difficult cases, you will need the help of a specialist or even buy a new microwave.

DIY repair requires certain skills and safety precautions:

1. Always unplug equipment before repairing.
2. Always wear special dielectric gloves.
3. Use tools with insulated handles.
4. Do not turn on a disassembled, damaged, open or empty microwave oven.
5. Discharge the capacitor before repairing. For example, with a screwdriver on the case (up to 1000 volts) or connect the contacts of the capacitor with pliers if the power is higher than 1000.
6. Do not leave metal objects and tools inside the oven.
7. Do not punch holes in the housing.

What to do if MVP heats dishes, not food

If your helper heats the plate herself instead of the contents of the plate, most likely you have chosen the wrong dishes. Utensils for microwave ovens should not contain metal, many water molecules, not heat-resistant plastic, melanin. These materials interact with electromagnetic waves, heat up, melt, and shiny metal objects reflect particles, an electric arc arises, which can cause a fire, a short circuit. Therefore, purchase special heat-resistant cookware with microwave markings.

We have listed the main reasons for such a problem as the lack of heating in the microwave. Remember safety precautions. We wish you a successful and easy repair!

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Design features

When diagnosing the state of the microwave oven and planning to repair or replace individual components, you need to take into account the design features of the equipment. Each manufacturer, when creating equipment, adheres to different technologies and uses individual components, therefore, it is possible to repair a microwave microwave oven only with certain knowledge.

Lg

Modern microwaves from LG are equipped with L-Wawe technology, thanks to which the generated waves propagate in a spiral manner and provide a more even and deeper penetration of heat in all parts of the dish. The special design of the inner surface of the housing allows the waves to be distributed throughout the chamber.

Samsung

The main distinguishing feature of Samsung's technology is the coating of the camera with bio-ceramics. This material is completely safe for human health, easily cleaned from contamination and has increased resistance to damage. Due to the low thermal conductivity of bio-ceramics, heat losses are reduced and the process of cooking and heating food is accelerated.

"Bork"

The new models of Bork microwave ovens provide a variety of programs that allow you to defrost food, perform quick heating, and cook food in different modes. A more complex control system often creates problems when trying to repair equipment yourself. Faced with a malfunction of the electronic components of the Bork microwave oven, you should seek help from specialists.

Daewoo

Microwave manufacturer Daewoo has one of the leading positions in the market due to the release of equipment with intuitive operation and affordable prices. One of the specific models is the oven with an additional compartment for making pizza and pancakes. In this variety, you can cook 2 dishes at the same time. The disadvantage is the complex internals, which makes it more costly to repair and replace components.

"Sharp"

Sharp manufactures furnaces with basic configurations that do not have any special characteristics. Modern varieties are equipped with touch screens and displays.

Panasonic

Microwave ovens of the Panasonic brand are distinguished by a variety of additional cooking and heating programs. A complexly designed control system in the event of a breakdown of the electronic component requires professional repair.

Elenberg

Elenberg products are built with a basic internal configuration to make component repairs easy. In case of breakdown of more modern varieties with a touch panel, it is worth contacting a service center.

Why the microwave does not heat up and hums a lot

Have you encountered the following: the microwave began to hum a lot during operation, there is no heating of your food?

Then you should understand the following reasons:

• struck the diode. The current moves in one direction, in the other, its path is closed. In such cases, the microwave will hum;
• the capacitors are dry. A large number of waves are collected, which are generated by these sounds;
• the magnetron has broken.Its malfunction and provokes to create a strong sound.

Remember that after disconnecting the microwave from the mains, it still contains a charge in the capacitors, which means that it can amaze you with a current of up to 5000 V. Work should only be done with instructions and protective tools.

What to do if the microwave stops heating?

There are times when a microwave that has served for so long seems to work, and the food is cold, and you have to resort to the old methods of heating. There are many reasons for this problem. This article will discuss these causes and options for correcting them.

The main causes of breakdown

If the microwave works for 3-4 minutes, and the food is still cold, there is a problem with the appliance's performance.

The main reasons for this failure:

1. It is necessary to check the correctness of the set mode. For example, “defrost” cannot be used as a heating function.
2. Voltage drops. This leads to problems with the operation of the oven.
3. Loosely closed door. Broken lock or latches.
4. Mains or high-voltage fuse blown.
5. High voltage diode and capacitor damaged.
6. Faulty feed-through condenser.
7. Damage to the magnetron and electromagnetic lamp.

The main guarantee of long-term performance of microwave ovens is careful handling of equipment. Do not put metal bowls, cups, heat in foil or dishes with a shiny border. Soiled walls need to be washed well and in a timely manner. If there are frequent voltage fluctuations in the room where the microwave is installed, install a regulator and a stabilizer.

Self-elimination of simple breakage

The main reasons for inoperability can be eliminated on your own, while saving a decent amount on repairs in service centers. A little patience and attentiveness combined with desire and that's it - the problem is solved.

Light breakdowns and their solutions:

1. Wrong mode. According to the instructions, set the mode and put the dishes with water in the oven for a couple of minutes. The wrong function may have been installed.
2. Low voltage. It is necessary to plug the stove into an outlet, if there are still appliances powered from the same source, turn it off.
3. Broken door. The latches trigger the magnetron when closed. To fix - replace the lock and check the microwave.

If, nevertheless, these actions do not help, the breakdown is much more serious and other methods are needed here.

Elimination of serious breakdowns

As mentioned earlier, there are several breakdown options. You can solve them in the following way.

If the reason is the fuse:

• unscrew the rear cover (put the screws in a box so as not to lose them);
• remove the defective part and replace it with a new one (differ in color, shape deformation, if visually do not differ, you need to check the resistance to identify an unusable element).

The reason is in the multiplier:

• check the resistance with an ohmmeter (weak - indicates a breakdown, and if the deviation is small - everything is in order and the reason is different);
• you also need to check the diode;
• replace the part with a new one (repairing a damaged one will cost more).

Feed-through capacitors of an EM lamp:

• check resistance;
• if, when checking the transformer, the voltage is below 220 W, the part is out of order and needs to be replaced with a new one.

Magnetron or magnetron lamp (one of the main reasons when the working oven does not heat):

• here the main problem is the inoperability of the filament;
• you can try changing the resistance to clarify the problem;
• the ideal option is to completely replace the entire part, since after a while, after repairing the thread, the problem will appear again.

General Tips

Having discovered a serious breakdown, you need to remember several rules for eliminating it yourself:

1. Before undertaking self-repair, carefully study the instructions and the diagram of the device.
2. When starting troubleshooting, disconnect the device from the power supply.
3. You need to buy parts according to the model in specialized stores.
4. After installation, check the device for functionality. The back cover must be closed when the oven is in operation.

Also, do not expect reliable and long-term operation from cheap equipment. Such devices are designed for a short service life, and it is rather difficult to find spare parts for them. Slightly higher costs for buying a well-known brand of microwave oven. But they guarantee long-term and reliable use, and in the event of a breakdown, you can easily find the right part.

In conclusion, it is worth noting that the above are the main reasons when a working microwave does not heat. Always remember before you run to the service center - you should carefully read the instructions and check out simple options for problems. This will help keep the family budget from unnecessary expenses.

The microwave has stopped heating and is humming

If the microwave has stopped regularly heating food and at the same time emits an uncharacteristic hum, then the reason may be as follows:

• Diode inadequacy. Its task is to direct current in one direction. If the part is out of order, then the microwave starts to hum and the food does not heat up.
• A defective capacitor generates waves and the device hums.
• Failure of the magnetron can cause buzzing and humming.

High voltage diode

Diode testing is almost never done due to its complexity. If it is suspected that the diode is causing the device to malfunction, then it is easier to replace. The check is carried out either by a hum when turned on, or by a blown fuse, or by a capacitor, which does not heat up normally.

High voltage capacitor

If the microwave hums when turned on, then it is possible that this capacitor is out of order. Checking it is simple: connect an ohmmeter and follow the readings. If the arrow moves, then the capacitor works, if not, then it is the cause of the breakdown. Please note that replacement or inspection takes place only on a charged capacitor.

Magnetron

If all the details show themselves to be workable, then most likely the matter is in the magnetron. A sign of inoperability is the humming of the microwave in the absence of heating. Visually inspect for cracks and carbon deposits and measure values ​​with an ohmmeter. If it was damaged, replace it with a similar one in parameters and dimensions.

Do-it-yourself microwave repair for more serious problems

There may be several reasons why the microwave stopped heating. Most often they are problems:

• control unit (violation of the timer);
• power network;
• fuse (a sudden power surge can damage it);
• capacitor;
• high voltage diode;
• magnetron (the most expensive part of a microwave oven).

Now let's try to figure out in detail how it is possible to eliminate such breakdowns - how to fix the microwave with our own hands.

Do-it-yourself microwave oven repair is possible, but requires care and accuracy

Do-it-yourself microwave oven repair in case of control unit failure and timer malfunction

First you need to unplug the microwave oven from the mains, unscrew the screws at the back, remove the protective cover. Next, we carefully examine the control board for burnout of conductive tracks, swelling, burnout of elements. It happens that the microwave begins to live its own life - it can spontaneously turn on, turn off, refuse to work. The problem here may be a malfunctioning touch panel. In any case, although such details can be restored, they will not work for a long time. It is much more cost-effective to purchase a new unit, keyboard, replacing the old ones.

IMPORTANT!

When purchasing replacement parts, select those marked with the same markings as those that were previously installed. So you save yourself from unnecessary costs. By the way, such purchases cannot be returned or exchanged.

Repair of the control unit - soldering jumpers instead of burnt tracks

The microwave is working, but has stopped heating due to problems in the power circuit

This happens quite often. The first step is to check the magnetron circuit fuse (high voltage). If it burns out, the illumination of the microwave oven and the rotation of the platform remain in working order, and the magnetron (microwave gun) is not supplied with power. This is treated by replacing the high-voltage fuse.

This is what a high-voltage fuse looks like in a protective casing.

Why the microwave works, but does not heat food: we check the capacitors

The microwave oven circuit contains a multiplier capacitor as well as feed-through capacitors. All of them should be checked with an ohmmeter (the multimeter also has such a function). It is they who can cause the microwave to spin, but not heat. If found to be defective, they should be replaced.

It makes sense to check the high voltage diode. If he does not "call" to either side, you need to replace him.

High voltage diode - if it does not ring, it should be replaced

The microwave oven works, but does not heat: we are looking for the reason in the magnetron

The main and most expensive part of a microwave oven is a magnetron. If all of the above problems are not confirmed, then the problem is more serious than originally anticipated. Most often, the filament burns out, which can be checked by measuring the resistance. If there is no resistance, then the fear of unnecessary costs is confirmed. This will be the reason that the microwave works, but does not heat. It makes no sense to repair the magnetron - the work is quite laborious. It's easier to get a new one.

Magnetron is the most expensive part of a microwave oven

IMPORTANT!

Before purchasing, rewrite the data of the old magnetron, its marking. It is better to take the burned-out part with you along with the rewritten marking for comparison.

When to ring a transformer

The transformer converts the value of the mains voltage, which is necessary for the operation of the magnetron. He needs to be given enough attention, as he often becomes the cause of the breakdown of the microwave.

Getting out of a standing transformer is one of the most common causes of breakdown.

Ringing of the high-voltage transformer is performed, provided that the load is disconnected, as well as the primary winding. The procedure should be carried out in this way:

1. Remove the terminals with pliers.
2. Check the resistance of the primary winding, the norm in the value of which is 1.5 Ohm. The indicator of the secondary heating winding and high-voltage winding are the corresponding values ​​- 0.1 Ohm and 110 - 120 Ohm.
3. If during the check it was not possible to ring, at least one winding is a sign of a failure of the transformer. Replacement is required, for its connection there is a special connector in the magnetron design.

You can find out the resistance value between the case and the terminals if you disconnect the terminals. If the process is successful, it is necessary to look for damage in the filter at the pass-through capacitors. To fix the problem you should:

• install a new capacitor or buy a filter assembly of a suitable rating;
• remove the magnetron to make sure the condition of the antenna cap;
• having found signs of combustion, damage to the case, and also having determined the resource of the magnetron insulator, replace the necessary elements, the main thing is that the parts match the size.

The microwave does not heat: reasons

The main reasons for the breakdown of a microwave oven are hidden in its improper operation.

Most often, microwave problems begin after:

• There is a metal object in the cooking chamber;
• Reheating food in utensils not intended for this;
• The oven was empty.

If there is a metal object in the cooking chamber, the microwave immediately starts sparking and does not heat the food. Breakage can occur if you use dishes that are not designed for this.If the dishes are closed, then upon reaching a certain temperature, they explode, and the food immediately scatters around the chamber, completely clogging up the parts of the oven.

Cheap microwave ovens can break down simply due to wear and tear on parts. To determine exactly why the microwave has broken, you need to know exactly how it works. Microwaves are generated by a magnetron that is connected to a camera and a waveguide. In some individual models, the waveguide is covered with mica, while in others it is covered with a plastic cover.

Powering the magnetron helps to provide:

• Transformer;
• Diode;
• Capacitor.

There is often a fuse in the supply circuit to protect the transformer from overvoltage. A fan is designed to cool the magnetron. To prevent the microwave oven from functioning with a not very tightly closed door, special interlocking microswitches are installed. That is why, until the buttons are pressed and the doors are not closed, power is not supplied. One of the reasons the microwave won't turn on is if these small parts stick or break.

The microwave oven has become simply an indispensable attribute in the kitchen, since many find it difficult to do without this helper, who will help to cook and warm up their favorite dish.

A breakdown of the microwave delivers a lot of trouble, therefore, it is important to know for what reasons a malfunction may occur in order to carry out an independent repair

If the oven has stopped heating food normally, then the reasons for this may be hidden in:

• Insufficient voltage in the network;
• A miniature switch has broken;
• Mains fuse blown;
• High voltage fuse has broken;
• The transformer is not supplying voltage.

Apart from this, there can be many other reasons why the oven stops working properly. Initially, you need to ring a multimeter to determine the voltage level in the network. Then you need to disconnect the device from the mains and check the miniature switch for operability. The check is carried out using an ohmmeter. If the designation on the scale is greater than 0, then the part is working normally, but if it is 0, then it must be replaced.

If no problem is found, then a mains fuse check is required. To do this, you need to determine the resistance with a tester. In the event of a condenser malfunction, then during operation of the microwave it makes a lot of noise

Important! If you do not have sufficient knowledge and skills to repair microwaves at home, you should take the device to a service center.