The microwave does not heat well but it works, what should I do?

A microwave is an indispensable item in the kitchen for many people. With its help, you can heat up food very quickly, it makes cooking comfortable and saves a lot of time.

But unfortunately, any equipment gradually breaks down.

In such a situation, the main thing is to understand why the malfunction occurred . If something that is in constant use breaks down, you want to fix it as quickly as possible so that you can use it again.

It should be remembered that the problem can be either serious or easily solvable . Some of them can be eliminated by anyone, while others should be eliminated by contacting a specialist.

In this article we will look at what kind of microwave oven breakdowns there are and how to fix them yourself.

Why problems might arise

As usual, the causes of microwave oven breakdowns lie in non-compliance with operating instructions. This accounts for most of the problems with household appliances and this case is no exception. Most often, problems begin after:

There is a metal object in the chamber during heating/defrosting/cooking. Most often this is a spoon or fork that is in a container with food. At the same time, the microwave begins to spark, and then begins to act up - it sparks and does not heat the food.
Another fairly common situation that often leads to breakdowns is heating in a closed container not intended for this purpose. When a certain temperature is reached, the dishes explode, food scatters throughout the chamber, clogging the oven parts. It is rare that such an incident remains without consequences (washing the camera does not count).

The arrangement of parts may be like this

Cheap stoves can often break down. They are made in such a way that they are repaired less often and new ones are purchased more often. And the last obvious reason is wear of parts. If your stove has been in service for a decent number of years, most likely the parts have simply exhausted their working life. As you can see, there are not many technical reasons. Basically these are erroneous actions of “users”. The result is that the microwave does not heat or does not turn on at all.

The principle of operation and design of a microwave oven

To understand why the microwave stopped heating and how to fix it, you need to understand the design of the equipment.

Microwaves, namely high-frequency radiation that heats food, are created by a magnetron. It is connected to the camera by a rectangular waveguide, which, in turn, can be covered with a mica plate or a plastic cover.

The power supply is provided by a transformer, which is assisted by a multiplier consisting of a diode bridge and a capacitor. The fuse protects equipment from overloads and short circuits. The fan cools the magnetron and drives warm air into the chamber, which speeds up the heating of the dish.

You can set the mode and time for heating food on the control panel. It can be either mechanical or sensory.

Microwave device

To make it easier to repair a microwave oven, let’s get acquainted at least in general terms with its structure. What interests us most is its “insides.”

Microwave oven device

The magnetron produces microwaves. It is connected to the camera by a rectangular waveguide. In some models, the waveguide is covered with a piece of mica (a gray-brown material similar to metal), in others it is covered with a plastic cover. The magnetron is powered by a transformer, capacitor and diode. The power supply circuit often contains a high-voltage fuse that protects the transformer from overload.

There is a fan to cool the magnetron. Warm air from the magnetron also enters the working chamber through the air duct, which speeds up the heating of food. Steam and excess air are removed from the chamber through special holes that do not allow radiation to pass through.

Microswitches for locking the closed door

To prevent the microwave oven from working with the door not tightly closed, locking microswitches are installed. As long as their buttons are not pressed (the doors are not closed), power is not supplied. When the door is opened, the power circuit is interrupted instantly. One of the reasons that the microwave oven does not turn on is the breakdown or sticking of these small parts.

The number of microswitches depends on the model. There can be from 2 to 5 pieces. Some manufacturers also use them in the start button and power control circuits. So one of the reasons why the microwave does not heat may be damage to the microswitch in the power control circuit.

An incandescent lamp is installed in the chamber for lighting. Most often it is located inside the air duct.

Operating modes are set from the control panel. It may contain electromechanical switches, or it may be based on a microprocessor. Digital control can again have options: there may be regular buttons that select the mode, or there may be a touch panel. If a problem occurs with the controls, it is better not to get into electronics without knowledge and skills. The only thing you can check is how well the conductors are holding. Everything else is only possible if you have the appropriate experience.

How does a microwave oven work?

To repair/maintain any equipment, including a microwave oven, you need to know the principle of its operation. Let's look at the basic elements and their purpose.

Magnetron

At the heart of a microwave oven is a magnetron, which, when turned on, produces microwave energy and distributes it throughout the interior.

The magnetron screen is located inside the microwave on the right behind the wall where the control panel is located. It is made in the form of a cover, which is attached to latches or screws.

The function of the screen is to protect the magnetron from particles of food from the cooking zone.

The device is connected to the camera using a rectangular waveguide, which is covered with a glass or plastic cover.

Power supply

Transformers-stabilizers, which are the most complex and expensive element, act as a power source.

As additional equipment, a multiplier is used, which includes a capacitance and a diode bridge.

After applying voltage to the magnetron, the fan also turns on, which distributes warm air and thereby speeds up the cooking process.

Frame

The microwave has a rectangular body, which is key when heating.

The heat and waves generated during operation are reflected from surfaces and distributed evenly inside.

An additional advantage is the rotation of the saucer on which the food is placed. This function is provided by a special motor.

Control Panel

The microwave oven is configured using the control panel.

Depending on the complexity of the equipment, it can be mechanical (rotating handles) or touch (buttons).

Additionally, a number of protections are provided to ensure safe operation.

For example, when the door is opened, the oven automatically stops working. There is also a timer that turns off after a certain time.

Door

When making a microwave oven, special attention is paid to the door. The gap between it and the body should be minimal.

An HF choke valve is installed along the perimeter, acting as a barrier to dangerous waves.

In addition, plastic that can absorb radiation is used in manufacturing.

About security

Contrary to popular belief, a microwave does not emit radioactive waves, so when heated, at least 75% of the nutrients in food are retained.

The microwave does not heat: simple reasons

There are situations when you put food on to warm up, everything seems to work, but even after a long period of time, the temperature of the food is insufficient or it is completely cold. The reason that the microwave does not heat can be either a serious breakdown or easily fixable reasons. Let's start with the easy one:

The microwave oven may not heat properly due to low line voltage. For normal operation of the magnetron, 220 V is required. If the voltage is lower, it will work, but the temperature will rise very slowly. The situation is treated by installing a stabilizer. Naturally, it is better at the entrance to a house or apartment, but you can install a small stabilizer only on this equipment.

If your microwave doesn't heat, you'll have to have it repaired.

All other reasons are more serious and must be dealt with separately.

How much does the repair cost?

If you lack experience, it is better to entrust microwave oven repair to specialists. Depending on the policy of the service center and the complexity of the malfunction, the cost of work may vary.

For example, for a simple repair you will have to pay from 1000 rubles, for work of average complexity - from 3000 rubles, and for solving a complex problem - from 6000 rubles. (at the end of 2022).

Common breakdowns:

Buttons do not work due to damage to the control panel - from 2600 RUR.
Malfunction of the magnetron, capacitor - from 2550 rubles.
Replacement of a fuse due to blown during a power surge - from 2600 RUR;
Sparking in the device - from 3150 rub.
The start button on the microwave oven (control unit) is not pressed - from 2900 RUR.
Damage to the heating element - from 3200 rub.
Door malfunction - from 2650 RUR.
Breakdown of the motor for rotating the plate - from 2550 rubles.
The device does not turn off (timer, switch) - from 2650 rub.
Microwave oven does not turn on (electrical circuit) - from 2900 rub.

The exact price is determined individually after diagnostics and determination of the malfunction.

More serious reasons

In this section, we will look at damage that can lead to the microwave not heating, although everything is spinning/lit. To restore performance is more difficult than in the previous paragraph, but not so much that it is impossible to do it yourself.

Approximate location of parts in a microwave oven

Fuse

Sometimes the microwave does not heat due to a faulty fuse in the magnetron power circuit. It is not available in all models, but it can cause the magnetron to not work. This fuse is sometimes installed openly, but most often in a protective casing (see photo), since it is located in a high-voltage circuit.

High-voltage fuses in microwave ovens can be placed in a protective casing

It consists of a glass flask with metal caps installed at the edges. Inside there is a spring-loaded wire soldered at one edge to the cap contact. Unlike conventional fuses, the wire does not burn out in this one. During prolonged operation, the solder heats up and softens, and the elastic force of the spring separates the contacts.

Structure of a high-voltage fuse

If the fuse does not ring and a break in the circuit is visually visible, there are two ways to solve the problem - replace it or restore the soldering. To restore the high-voltage fuse, you must carefully remove the metal cap from the side from which the wire was unsoldered and solder it in place. Return the cap to its place and check whether it is heating or not.

Magnetron problems

There are several damages associated with the magnetron. Let's start again with the simplest thing - weak contacts. Wires from the filament winding of the transformer come to the terminals (connector) of the magnetron. They should be difficult to remove. It is possible that the contact has worsened due to heating. It can be improved by additionally crimping the contacts with pliers.

Read also: The screwdriver button does not work

Sometimes the microwave does not heat due to damage to the magnetron antenna cap. If the cap is simply blackened or there is a frozen drop of metal on it, but there are no extra holes, you need to clean everything down to bare metal and make the surface smooth. You need to work with fine sandpaper. We achieve maximum effect - everything should be even/smooth, preferably to a mirror shine. But don't rub the metal to holes. Upon completion of work, carefully remove all dust. The best way to do this is with a vacuum cleaner.

Antenna cap is damaged

If the cap is melted - as in the photo above, you need to make sure that the magnetron itself is not damaged and that a vacuum is maintained in the middle. To do this, carefully remove the cap and inspect what’s underneath. If the metal is intact, you can simply replace the cap. If not, you will have to change the magnetron, but at the same time you need to think about the feasibility of such a repair - the price of this spare part is high, perhaps you should just buy a new furnace.

How to replace the magnetron cap? It is very difficult to find it on sale - it costs a penny and is not profitable to sell. There is an option - turn it on a lathe. If this method does not suit you, you can make one from an old electrolytic capacitor of a suitable size.

Old damaged cap and new one from the capacitor

We select an element of a suitable diameter, cut off the required piece of the body, and carefully drill a hole in the center. The match in all sizes must be perfect. After this, we clean the body with the finest sandpaper and polish it: the quality of the microwave’s operation depends on the conductivity of the cap. We put the finished cap in place and check the work.

If you still decide to replace the magnetron, then take it with you to the store. The new one must match the output power, the antenna must be the same length, the mounting lugs must also be located in the same place and on the same side. Only then can it be installed in place of the old one.

Problems with mica plate

On the camera side, the waveguide output is covered with a mica plate. Sometimes the microwave does not heat because carbon deposits have formed in it and the waves simply cannot overcome this obstacle. Also, due to such damage, sparks and something similar to lightning or even fire may appear during operation.

Darkening visible on the mica plate

In this case, remove the plate by unscrewing the screws (from two to eight pieces). If there are no irreparable changes (no hole), you can try to clean the blackened area. We take fine sandpaper and carefully clean everything off. Carefully remove the dust (you can use a vacuum cleaner) and put the plate in place. To be sure that everything works, you can turn it upside down.

If there is a hole in the plate, it is better to replace it. This spare part is on sale; stores know about mica for microwaves. Place the new plate in place (you may need to drill holes for fasteners) and check it. If the microwave did not heat the food because of this, everything should work.

Capacitor burnt out or diode faulty

If the microwave stops heating, everything turns on, buzzes, and spins, but the food remains cold, it may be the capacitor. We take a tester and check it. We set it to resistance measurement mode.

Microwave capacitor

If during measurement it shows a break, it is not working; if it shows a small resistance, it also needs to be replaced, since it is broken. Only if, when touching the capacitor, the arrow “flies” to infinity, it is in normal condition.

Checking a high-voltage diode is not an easy task, so most often it is simply replaced. It doesn't cost so much that it would be a problem. Naturally, the parameters of the new spare part must match. There can be many other reasons why the microwave does not heat - you need to consistently check all the elements and conductors. But since the manufacturers’ schemes differ, you need to figure it out on the spot. In principle, in the process of identifying all the breakdowns described above, you will see if the wire has become unsoldered/frayed, the soldering has come off, etc. You monitor and eliminate all these nuances. In theory, it should work.

Let's imagine a situation: when getting ready for work in the morning, you are left without a hot sandwich: the microwave does not heat the food. Outwardly, everything is in order - the stove lights up, turns, but does not heat up. Let's figure out what the problem is and what to do in this case.

Complex malfunctions, the microwave heats up but makes a humming sound

In more complex cases, we are talking about some kind of equipment malfunction. After turning on, the tray rotates, the light is on, but the microwave oven does not heat anything. There may be several reasons for this.

Control block

To determine whether the control unit is faulty, it is important to have some experience. In the absence of one, it is better not to meddle with this mechanism due to the risk of damaging expensive elements.

For beginners, the best way is to replace the equipment or update its firmware.

Magnetron

The most difficult situation is when the microwave does not work due to damage to the magnetron.

The malfunction of this part may be due to the following reasons:

Poor contact connection. If the contact weakens, heating occurs at the connection point, which leads to the impossibility of normal operation. To fix the problem, you need to compress the contact group using pliers.
Deterioration of the metal. Many microwave ovens have a hole in the cap through which you can look at the metal elements and evaluate their condition. If the metal is intact, the problem is in the cap, which requires replacement. If the metal is damaged, the microwave may break. The solution to the problem is to replace the magnetron, which is expensive, or to buy a new microwave oven.
Traces of burnt or metal drops on the surface. To remove them, use sandpaper to clean the cap and thus improve its conductivity.

Fuse

In a situation where the microwave does not work, check the integrity of any fuses that may have blown. Externally, such elements look like a glass flask with metal inserts inside.

There are caps installed on the sides, to which a wire in the form of a spring is connected.

The current passes through the fuse and if this parameter exceeds the optimal norm, the insert burns out.

There is also a situation when the wire simply comes off, which is why the voltage does not flow into the microwave oven.

Mica plate (magnetron screen)

A special plate is installed inside the heating zone, which can be inspected visually and identify a malfunction.

With prolonged use and lack of proper care, soot may appear on this element and a thick layer of fat may accumulate. This dirt interferes with the normal operation of the element and causes the microwave oven to not work.

In addition, contamination may cause sparking or cracking noises. In the most difficult cases, the part may even catch fire.

Capacitor, transformer

If the microwave oven does not heat food and makes a lot of noise, in 90% of cases the cause is a burnt-out capacitor.

If smoke appears after turning on the device, this indicates damage to the transformer.

A malfunction can be indicated by normal overheating without damage to the part.

Diode

A broken diode can lead to heating and damage to the capacitor.

Diagnosing such a malfunction is a complex process, so replacement is carried out even if a breakdown is suspected.

Inverter

The purpose of the device is to determine the temperature inside the chamber and the products themselves.

Control is carried out using sensors that can fail or provide incorrect information.

In both cases, the microwave oven simply will not heat the food.

Timer

If damaged, the timer does not work correctly and begins to randomly turn on and off the equipment.

It makes no sense to repair this part, so the only correct solution is replacement.

How does a microwave oven work?

First, let's explain the principle of its operation. The basis of the machine is a magnetron, which creates an electric field. It acts on the liquid molecules in the product. They start to move. When they rub against each other, heat is generated. Due to this, as well as the use of additional devices, the equipment performs many functions - heating, defrosting, grilling and others.

What to do if the microwave oven heats the dishes and not the food

The principle of operation of a microwave oven is that microwaves emitted by a magnetron act on water molecules contained in food. They begin to move chaotically, and the food heats up evenly. Heat from heated food is transferred to the dishes. If during heating the food does not heat up, but the plate becomes hot, this indicates that the dishes are not suitable for a microwave oven.

Special dishes are produced for microwave ovens, which have a symbol that allows use in the oven. If there is no special container, the existing containers are tested. The plate is placed in the microwave, a mug of water is placed next to it and the device is turned on at full power for 1 minute. If the plate is not hot, it means it is suitable for heating food.

Glass containers are suitable for cooking and heating in the microwave. It practically does not heat up. Plates with thick walls made of porcelain, ceramics and earthenware also show themselves.

Do not use thin glass and crystal, porcelain cups with thin walls, or ceramic dishes without glaze - these containers can crack when exposed to microwaves. Do not use gold-plated utensils.

Do not use in microwave oven:

metal utensils;
utensils containing metal or having a metallized coating;
low-melting plastic;
disposable containers;
aluminum molds.

Use cheap Chinese microwave containers with extreme caution. When heated, they can melt, releasing substances harmful to the body.

Important! Do not use utensils that cause sparks. This may cause the device to malfunction.

To ensure that the microwave oven works for a long time and without interruption, you need to select the right dishes. If you are using proven plates, and they heat up, but the food does not, this indicates a breakdown of the equipment. For diagnostics and repairs, contact a workshop.

Rules for caring for a microwave oven

Following simple recommendations will allow your home assistant to serve for a long time:

Do not use metal containers or metal-coated utensils for cooking. The oven, acting on them, heats the dishes themselves, and not the food.
Do not place eggs, vegetables, fruits or other foods that contain a lot of water in open containers. Heating from the inside, they will burst and splash the camera.

To avoid fire, do not turn on the appliance without loading food.

Prevention of breakdowns

To protect your microwave oven from damage and extend its service life, you must follow a number of simple rules:

Heat food only in the “correct” containers, which are recommended for use in a microwave oven. It is prohibited to use metal containers or utensils with metal, silver or gold plating. Otherwise, there is a high risk of the equipment catching fire.
Do not place anything on top of the microwave.
Do not cover food containers completely while heating. This is important for steam release.
Do not use carriers to connect.
Do not drink alcoholic beverages.
Do not boil/heat eggs or other foods that are restricted by the microwave manufacturer.
Cover food with a special cap to protect the inner surface from grease. This simple rule can significantly extend the service life of the product.
Install the microwave oven taking into account the manufacturer's recommendations.
Do not turn on the microwave without food inside.
When cooking vegetables, make cuts to allow the internal juices to escape.
Close the doors carefully to prevent damage to the latch and other parts.
Constantly clean the microwave from grease and food debris, especially pay attention to the magnetron screen. Dirt accumulated on it leads to sparking and the appearance of extraneous noise.

If possible, use heat-resistant dishes made from special glass.

Its features include the ability to evenly distribute heat, which allows you to cook food faster and avoid consequences.

It is better to use a transparent and oval container for heating/cooking. Alternatively, you can use porcelain, glass, special plastic or ceramic dishes.

Causes of malfunctions

Even products from such well-known companies as LG, Samsung, Daewoo cannot last forever. Practice shows that the equipment of these companies, Scarlet, Panasonic, Supra, Bosch, works great for 5–7 years. Then problems may arise.

For example, outwardly everything seems to be working, but the food is poorly heated or not heated at all. In this case, the unit makes noise or squeaks, but at the same time the stand rotates. It takes a long time to heat food. Such signs do not always indicate that the microwave is broken and needs to be taken in for repairs. We need to find out why it doesn't work. Let's go from simple to complex.

It happens that the user, in a hurry or because of forgetfulness, did not switch the mode on the display from defrosting to cooking. As a result, the oven heats poorly.
For normal operation, a mains voltage of 220 Volts is required. A drop of even 10–20 Volts will result in the stove not heating well. Use an uninterruptible power supply or voltage stabilizer.
Sometimes owners simultaneously connect several electrical appliances to the network using tees and extension cords. Then the socket cannot withstand the load, the equipment does not warm up well or turns off. Use a separate power source for each device.
If the microwave heats up less well or only heats up every once in a while, the reason may be a loose fit of the chamber door. The latch needs to be adjusted.

Read also: Why do you need a surge arrester in the shield?

If all this does not help, let's look deeper into the problem and try to find the cause of the breakdown. The microwave oven hums, buzzes, stops heating, but still works if the following are out of order:

One of the fuses.

The problem may also be in the inverter, if you have the appropriate type of microwave.

Some problems you can fix yourself, while others are better handled by a specialist. Statistics say that in four out of five cases, after self-repair, you still have to contact a workshop.

How to detect problems with a microwave oven?

If you decide to find out for yourself why the microwave stopped heating, then it is best to follow simple instructions:

Check the voltage at the outlet - even small deviations from normal values affect the quality of heating food.
Check how well the door latches work.
Turn off the power to the device and remove the top cover.
Inspect the fuses: if these elements are damaged, you will immediately notice that they will be swollen and blackened. If there is no damage, then you can check it with a tester.
Using an ohmmeter, check the diodes and capacitors.
As soon as the stove has cooled down, inspect the magnetron and the contacts leading to it, check the resistance.

DIY repair

When starting work, make sure that the warranty period for your equipment has expired, otherwise you will lose the opportunity for free service at the service center.

Screwdriver Set;
pliers;
soldering iron;
ampere-voltmeter;
rubber gloves (thin household gloves are fine).

First, re-read the instructions. For example, the passport of a Samsung microwave oven discusses the causes of common malfunctions and explains how to eliminate them.

Attention! A microwave oven uses high voltage current. Even when disconnected from the network, it remains on the capacitors for some time. Therefore, after de-energizing the device, wait 10 minutes or discharge the parts.

After removing the screws on the back wall, carefully remove the housing cover. Inspect the device carefully, using a flashlight if necessary. An unpleasant smell of burning insulation, obvious deformation of parts, cracks or leaks will immediately indicate the location of the breakdown.

If the listed signs are absent, start searching.

First of all, measure the voltage in the network with a voltmeter and test the heater wire.

Using a tester, make sure that the operating voltage on the primary winding of the transformer is also 220 Volts.

Next, check the door microswitch with an ohmmeter. If it is working properly, the scale will show more than zero.

Visually inspect the power fuse. The absence of thin wiring inside indicates that it has burned out. You can check its resistance with a device.

Next, ring the high-voltage fuse, which is covered with a casing. The ohmmeter needle should deviate from 0 if it is intact.

Now let's move on to testing the multiplier, consisting of a diode and a capacitor. The ampere-voltmeter needle, which has deviated to the maximum, indicates a working capacitor. If it breaks down, the part must be replaced along with the diode.

Before checking feed-through capacitors, use an electrically insulated screwdriver to short their terminals to the housing. We touch the contact of the part with one probe of the measuring device, and the metal with the second. The sensor should show no resistance. This means the capacitor is working. After that, we check it for breakdown. There should be a resistance of 0.1 Ohm between the contacts of the capacitor.

After turning on the microwave for five minutes with a glass of water, measure the voltage in the primary winding of the transformer with an ampere-voltmeter. It should be 220 V.

Having purchased parts that match the parameters in a specialized store or radio market, replace the faulty ones using a soldering iron.

And finally, test the magnetron. When examined, its breakdown is indicated by carbon deposits. If this is not the case, look at the soldering points of the coil contacts and connections to the capacitors. Strip or solder them. The resistance of the assembly filament during testing should be 2–3 ohms.

You should not change this most important element of the microwave oven yourself, so as not to permanently damage the equipment!

Determining the reason why your device stopped heating and repairing it, if you have experience and the necessary tools, you can do it yourself.

The reason that the microwave works but does not heat food can be not only a serious breakdown, but also a minor malfunction in which any housewife can restore the device to working order. As a rule, the reasons for the entry of microwave ovens are banal and are the same even for models from different manufacturers. Below it is said in which cases you can repair a microwave oven yourself, and in which cases only a specialist can return the oven to work after replacing the damaged parts.

Repair rules

Unqualified repairs often lead to negative consequences in the form of health problems or worsening microwave malfunctions.

To eliminate such moments, follow these rules:

Always relieve tension before carrying out repair work. To do this, remove the cord from the outlet.
Use protective gloves made of dielectric material that can protect against voltages up to 1000 V.
Perform repairs/diagnosis using tools that have insulated handles.
Do not apply voltage to the microwave after parts have been removed, without food, with the door open, or if there is a suspected malfunction.
Discharge the capacitor before checking, removing or replacing. For this
Be careful and check the microwave oven for metal objects inside after repair. ATTENTION: It is normal for a spark to jump between the housing and the capacitor.
Do not drill holes in the case, as this may damage the device.

Frequent and simplest faults

A situation often arises when the owners of a microwave oven that does not heat food vainly blame the manufacturer for a cold breakfast. In fact, the reasons for unsatisfactory operation may be completely unrelated to the condition of the internal components of the device.

The performance of the furnace is directly affected by the operating mode and quality of heating. Practice shows that even a deviation of 20V can cause the device to slightly heat the dishes, while the food remains cold. A UPS (uninterruptible power supply) will help you avoid such troubles, which will also protect other connected devices from combustion.
If one outlet or branch of the household electrical network is overloaded, the microwave may also not have enough current. This can happen when you try to connect the stove to the same outlet as a washing machine, dishwasher, or electric stove.
If the microwave hums and regularly rotates the dishes on the stand, but the food remains cold, the problem may be in the door, namely, not closing it tightly. In some models, after long-term use, they simply need to be closed more tightly, while in others, the latches that press the magnetron switch simply break. The repair consists of completely replacing the latches.
Often the cause of “breakdown” is the choice of the wrong operating mode of the microwave oven. The defrost function, for example, will not be able to make food warm.

This list contains faults that are not related to the output or malfunction of functional parts of the device. Such cases, which can already be called breakdowns, are described further.

Troubleshooting

A huge number of reasons why a microwave oven does not heat can be detected and solved quickly and in a timely manner. First of all, you need to prepare some tools in advance - a screwdriver, measuring instruments. These include an ohmmeter - a device that will do an excellent job of diagnosing problems in a microwave oven.

Microwave works but doesn't heat well? Troubleshooting methods:

Incorrectly marked mode - use the instructions to set the desired command (“warm-up”); turn on the oven for a while and make sure that the food is heating up - the problem is solved.
Insufficient voltage - take care to install an uninterruptible power supply.
Problems with the normal functioning of the door - replace parts.

If the microwave oven is no longer in good working order and cannot cope with direct tasks, first refer to the instructions, which contain a list of tips and valuable recommendations on why the oven fails. If you don't find a useful answer, check an item such as voltage. If everything is in order, unplug the oven and check other elements - microswitches.

In some situations, it is impossible to restore a non-working Samsung microwave or a device from another manufacturer. Even troubleshooting a magnetron is too costly a process. It is more rational to purchase new equipment.

Troubleshooting

Before you start disassembling the microwave oven and searching for failed modules, you must read the instructions and user manual. Often in it you can find the answer or tips on how to make repairs yourself.

The first step in checking the internal circuitry is to measure the voltage. As mentioned above, the operation of the magnetron emitting microwave radiation may depend on this indicator. The operating voltage range is indicated in the technical documentation of the furnace.

If the voltage is OK, you should check the operation of the door. Using a small switch on the side, it sends a signal to turn on the magnetron after closing. It is checked using an ohmmeter.

Read also: How to check the horizontal level without a level

Fuse

Further checking of the oven’s serviceability is carried out in the functional block, to access which you need to unscrew the back wall. After this, you need to first check the high-voltage fuse. Visually - the integrity of the filaments and glass casing, and hardware - for resistance. One way or another, the repair here is very simple and easy to do yourself - you need to replace the part with a new one. When going to the market or store for a replacement, it is better to take the broken element with you in order to accurately select the model. The use of so-called bugs is extremely undesirable - they are a fire hazard, and the fuse is not so expensive as to risk it.

Multiplier

This element of the internal structure of the microwave oven consists of two parts - a capacitor and a diode. The serviceability of the first can be checked with an ohmmeter, despite the fact that it is intended for alternating current networks. If the tester's needle deviates and goes to infinity, everything is fine - the capacitor takes on a weak charge. If the arrow remained motionless, this would indicate a broken contact. And if the tester immediately signals a small resistance, there is a breakdown. Be sure to discharge the capacitor before diagnosing. Such a device is inexpensive, so it is better to replace it immediately.

By the way, it is damage to the capacitor that is often the reason why the oven hums when it turns on, but begins to heat poorly. In such a situation, the device may make strange sounds and buzz.

Electromagnetic lamp capacitors

To check the capacitors of an electromagnetic lamp, you must first discharge them using an indicator screwdriver (short-circuit the terminals one by one). The reason for the failure of this element is the short circuit of the capacitor terminals to the housing. To check, take an ohmmeter, one probe of which is installed on the metal body, and the other on the terminal of the container. If there is no resistance, the part must be replaced. The same will have to be done if the resistance between the contacts does not meet the standard of 0.1 Ohm.

Here the tester checks the primary winding of the transformer. The voltage on it should be 220V. To test heating, place a dish or glass of water in the chamber.

Magnetron

The magnetron is a key element in a microwave oven. Repair experts say that this is often the reason why the microwave oven becomes weak or stops heating food altogether. When turned on, the magnetron emits electromagnetic waves with a frequency of 0.5 to 10 GHz into the microwave chamber. To put it simply, under their influence, the hydrogen atoms in food begin to rotate, resulting in heating.

However, it is too early to draw hasty conclusions - the cause of the malfunction is not always the electromagnetic lamp itself. For many microwave ovens (even such trusted brands as Samsung, Daewoo, LG, Indesit), the magnetron stops turning on due to the loss of reliable contact between the power terminals and capacitors or the desoldering of the induction coil contacts. In such a situation, repairs can be done by yourself without any problems.

If the microwave turns on but does not heat, the filament installed in the magnetron may have broken. To check this malfunction, you need to measure the resistance on the thread. If everything is normal, then the needle of the device stands at the 2-3 ohm mark; if it breaks, it goes to infinity.

Please note that the radiator and metal body of the electromagnetic lamp, after it turns on, heats up to at least 150˚C. If you turned it on before to check the transformer winding, wait until the device has completely cooled down.

If, after all the steps described, the reason why the microwave oven turns on but heats up weakly is not found, the problem is that the magnetron is broken. In this case, it is better not to try to figure out the structure of this element on your own. This will take a lot of time, and DIY repairs are unlikely to be effective. The easiest way to fix the problem is to replace it.

To purchase a suitable device, you need to write down all the technical characteristics (for most furnaces they are on the back panel) of the device and magnetron: power, filament voltage and current, cathode voltage and anode current; and contact your service center with this information. Self-installation of the magnetron is acceptable, but it is better not to save money and, to be on the safe side, give this work to a specialist.

Diagnostics and troubleshooting

Before carrying out repair work, it is important to carry out diagnostics to determine the malfunction.

In a situation where the microwave does not work, turns on every once in a while, hums or does not heat, but works, do the following:

Check the voltage supplied to the transformer. To do this, use a regular multimeter and follow safety precautions. If the voltage drops below 215 Volts, connect a stabilizer or wait until this parameter normalizes.
Check that the door latch is working properly.
Make sure that the contact connections are reliable, as well as the serviceability of the main elements.
Disconnect the microwave oven from the power supply and remove the upper part of the housing.
Remove the chip from the magnetron and check it.
Place the magnetron terminals in place.
Check the capacitor.
Check diodes.
Check the integrity of the fuses. Burnt-out elements are immediately visible by blackening.
If the latter burns out, check the multiplier nodes.

We will consider the features of checking each of the above elements in a separate section below.

After identifying the malfunction, you can decide whether to repair the microwave oven.

If there is a crackling sound, do the following:

Determine which part the cracking is coming from.
Turn off the power.
Remove the mica plate and replace it (costs about two dollars) if it is burnt.
Unscrew the magnetron, which is attached to 2-4 screws.
Remove the cap that is located at the outlet. If it is tight, loosen it and remove it by hand.
Look at the metal outlet under the cap to see if there is a breakdown. If such traces are present, the magnetron must be replaced.
If the feed-through capacitors fail, they must be replaced.
If the cap is burnt out, replace it.
Replace the capacitor if it is the one that fails.

How to extend service life

The reason that a microwave oven begins to heat food poorly or stops doing so is almost always due to wear and tear of one or another functional element. Of course, during the warranty period you need to use the services of a service center. But in order for the device to work for a long time even after the expiration of the warranty, and in order to avoid having to do repairs yourself in order to save money, you need to avoid actions that shorten the service life.

It is better not to use metal utensils and generally avoid getting metal objects (forks, spoons, etc.) into the oven. To ensure that food is heated while using the microwave, and the dishes themselves remain cold, you need to avoid materials such as: crystal of different thicknesses and with different thicknesses, porcelain and glass with patterns of gold paint, disposable plastic tableware, ceramics without a protective glaze, aluminum molds for baking.
Do not turn on the device idle - without food or products.
It is also undesirable to heat liquids and raw eggs in containers that “explode” when heated.
Failure of the touch panel is also a common malfunction, so it is advisable not to put too much pressure on it or get it dirty. For many ovens from well-known manufacturers, a breakdown of the touch panel is displayed on the display with a service code, for example, SE (each manufacturer uses different designations).

To avoid problems with microwave oven repair, you need to pay attention to devices manufactured by reputable manufacturers. No matter how much these models cost compared to their Chinese counterparts, the quality of the build and the materials used pay off in the future. It is difficult to repair a cheap “nameless” device with your own hands because it is not easy to find the necessary parts for it, and the technical documentation does not always correspond to reality. And craftsmen who encounter such a device may ask for a lot of money for repairs, since this will also be problematic for them.

The main reasons why a microwave does not heat well

The microwave does not heat food well for external and internal reasons. External ones are eliminated on their own. In case of internal problems, the microwave oven is disassembled or sent to a workshop.

Troubleshooting yourself

There is a category of minor faults. which even a non-specialist can fix at home.

Reducing electrical voltage

When the voltage is less than 220 V, the microwave radiation power drops and the device heats up weakly. If the voltage drops for a long time, the magnetron stops working.

If the problem arose due to unstable voltage in the network, install a stabilizer. If the outlet is overloaded with several devices that operate simultaneously, separate power supply lines are laid for each of the devices.

Selecting the wrong mode

If the oven is set to the Defrost function, the food will not heat to the required level. Therefore, when heating a dish, set the appropriate mode.

The door does not fit tightly to the body

During operation, the device wears out. The fasteners that hold the door in place become loose and wear out. The lock clicks weakly and a gap forms. Cold air from the external environment enters it. This increases the heating time of the food.

To detect a loose fit, a sheet of paper is passed between the door and the body. If it passes freely, then there is a problem. To eliminate it, tighten the connections in the microwave oven or change the latches.

The device is dirty

If the microwave takes a long time to heat due to contamination, it should be cleaned. In order for the household appliance to work stably and for a long time, it is periodically washed with a damp sponge to remove food residues and grease.

Fuse failure

Failed fuses are replaced with new ones. To do this, remove the back cover: damaged ones are black and swollen in shape.

Important! When disassembling a microwave oven, be sure to disconnect it from the electrical network.

Contact the master

More complex breakdowns require certain knowledge and are repaired by professionals.

Damage to the timer or control panel

Occurs during prolonged use of a household appliance or due to careless handling (most often found in Samsung microwave ovens). The timer turns off before the set value, the food does not have time to warm up.

Inverter failure

The inverter is responsible for saving consumed electricity. Its breakdown is a common problem typical for inverter microwaves. The malfunction is repaired at the service center.

Transformer failure

Typical for inexpensive household appliances.

Control unit failure

A specialist disassembles the microwave and checks fuses and diodes. Defective ones are replaced.

Magnetron malfunction

The magnetron powers the microwave oven. It lasts 5-7 years, cheap Chinese devices last about 1 year. During operation, the microwave power decreases and the oven begins to heat poorly. Black spots on the walls indicate a malfunction of the magnetron; the microwave produces a loud buzzing and hissing sound when turned on. To restore emissions, they use sophisticated equipment that is not available in most service centers. Therefore, the magnetron is changed.

Advice. If the warranty period for the device has not expired, it is taken to a service center for repair.

Other reasons

If your microwave oven warms up your food after a time or two, it may be due to:

Microswitches that do not operate when the door is closed. To fix the problem they are changed.
Loose contacts on terminal blocks. To solve the problem, the stove is disassembled and the bolts are tightened.

Features of repair of some brands

The causes of breakdowns for different brands are identical, but the repair of a certain brand may differ slightly from its analogues. Let's look at the features of the most popular brands of microwave machines.

Samsung	Microwave ovens from Samsung rarely break down - the mechanical parts are very strong, so problems with latches can be eliminated by almost 99%. If there is a malfunction, you should immediately check the electronics.
Rolsen	The Rolsen brand cannot boast of impeccable reliability. Breakdowns and even short circuits of equipment are common, so it’s worth looking for a different brand.
Panasonic	Budget models from the Panasonic brand often suffer from rust. This will not directly lead to malfunctions, but will accelerate the wear and tear of the equipment.
LG	Another brand of microwave ovens that is reliable. But there are also two weak points in the LV: fuses and capacitors - they must be checked first.

Also popular brands of equipment include:

Sharp is a popular brand with a wide range of sizes, but the actual size of the camera may be smaller than stated;
Supra is a budget equipment with normal quality, sometimes breakdowns occur, but most customers are satisfied;
Elenberg is also a budget brand, but has a short warranty - only for a year;
Bork - models are distinguished by high functionality and stylish appearance, but we must take into account that the brand is Russian, and the spare parts are Chinese;
Scarlett is a British brand that wanted to produce equipment in Russia, but still chose China;
Daewoo is one of the leaders in electronics, simple controls and stylish models, low cost and good quality. There are retro models;
Erisson - simple, concise and budget models. Ideal for a cottage or rented apartment;
Vitek is a very popular brand, there are many models with different numbers of functions.

Microwave doesn't heat well

A microwave is a household appliance that most of us find difficult to live without in the kitchen. It's in the kitchens of our homes and the dining areas of organizations. It is installed in dachas and summer kitchens. This easy-to-use household appliance helps us quickly heat up food and makes cooking quick and convenient. Unfortunately, like any other household appliance, a microwave oven can break down. Everyone knows that when a malfunction occurs in any device, the main thing in eliminating it is to identify its cause.

At the same time, the breakdown can be both serious and completely removable on your own. Today we will pay attention to such a malfunction as poor heating of the microwave and how it can be eliminated.

The simplest causes of problems and tips for eliminating them

Microwave oven spins but doesn't heat food? In addition to the lack of heating, pay attention to additional signs - for example, the microwave is humming or making a lot of noise.

First of all, you should look at the instructions, since they contain tips that can help you understand the reasons for the malfunction of the equipment. But the main problems are similar, so we will analyze them. Let's start with the simplest breakdowns that can be fixed at home.

Insufficient voltage

The required voltage in the network for proper operation of the microwave is 220 V. If this figure is lower even by 5-10 V, then the equipment will heat poorly, weakly, or every once in a while - depending on the voltage value. To prevent such surges, it is necessary to install a voltage stabilizer.

Another option in which a lack of voltage may occur is to connect large household appliances such as a refrigerator or washing machine to the same outlet, or even use a double/tee. Such actions are unacceptable, since the microwave oven must have its own free outlet.

Technical difficulites

It happens that the problem is not in the microwave oven itself, but, for example, in the wire or socket. To make sure that this is exactly the problem, you just need to connect the equipment to another outlet and carefully inspect the cord. If problems are found, either the outlet or the cord will need to be replaced.

Door

The microwave is designed in such a way that it will never turn on when the door is open. This is facilitated by special latches on the doors. If they are broken or simply do not fit tightly, then the microwave may not heat the food as well or may not heat the food at all. In this case, there are only two options - change only the latches, or the entire door.

Wrong mode

The reason that the heating in the microwave does not work may be due to ordinary human carelessness. This happens if the previous action of the microwave was defrosting, and then they forgot to turn off or change the function. In this mode, food will never warm up. All that is required in this case is to set the heating mode and, if necessary, increase the power.

If all of the above points have been checked, but the microwave still does not heat food or does it poorly and for a long time, then, most likely, a really serious breakdown has occurred, which is not always possible to fix without a professional.

How to fix minor problems: 3 methods to solve the problem

Most of the above reasons why the microwave does not heat can be corrected at home yourself, while significantly saving the family budget for repairs. The most important thing is to have and be able to use a screwdriver and instruments for measuring resistance and voltage.

If you have instructions and a user manual, be sure to read it, perhaps there you can find the cause of the breakdown and a method for eliminating it.

Below are several options for mild microwave oven malfunctions and methods for eliminating them.

Wrong mode

This often happens, especially with new microwave ovens, that the operating mode is simply set incorrectly. Therefore, the microwave works, but does not heat the food. And, perhaps, this is the most insignificant cause of this problem, which can be eliminated without major repair work and replacement of parts.

To do this, you need to make sure that the required mode is set on the device control panel. Usually this is a function of heating food. By turning to the user manual for help, you need to set the appropriate command. Next you need to check the serviceability. To do this, you need to put a glass of water or some food in the oven and turn it on for 1-2 minutes.

If the temperature of the food has changed, then most likely the problem was only in the incorrectly set operating mode. Quite often, users set the defrost or grill mode instead of the heating mode. This prevents the food from heating properly because the wrong function has been selected.

Insufficient voltage

Unfortunately, today many houses still have old wiring installed, which was carried out during the construction of these houses. However, it is not designed for the number of electrical appliances that are now used in every apartment. This can cause low voltage in the home network and, as a result, malfunction of household appliances, including a microwave oven.

To confirm or rule out insufficient voltage, you must use a voltmeter. If there is none, then you should adhere to the following algorithm of actions:

if in the apartment, in addition to the stove, several other devices are turned on (this is especially true for those cases when the devices are plugged into the same outlet as the microwave oven), they must be de-energized;
install an uninterruptible power supply, which will stabilize the voltage.

If several electrical appliances are turned on simultaneously in a room, the voltage may not be enough. And if there is overvoltage, the wiring may burn out or the electricity will simply turn off.

Door fault

This is also one of the most common problems with microwave ovens. Often the door simply does not close tightly, which can be caused by either foreign objects or failure of the latches. It is the latches that play an important role in the proper operation of the microwave - they trigger the magnetron.

If the problem lies not in the ingress of debris, but in the malfunction of the latches, then they simply need to be replaced with new ones. During operation, ensure that the door is closed tightly.

Why does a microwave oven not heat food well?

We are sure that each of you has encountered the problem of poor heating of food in a microwave oven. The reason for this “behavior” of a microwave oven can be various minor defects in the device.

Common defects

The door does not fit tightly to the body. Such a breakdown can occur with a long service life of the stove and wear of its parts - the fasteners become loose, the connections become loose and the lock on the door does not snap as tightly as before;
Electrical voltage surges or levels that are too low;
Connecting several devices to one current source at once, which leads to a drop in power in the network and can cause a failure;
Incorrect choice of operating program;
Severe contamination of the microwave oven;
Failure of the fuses installed in it.

All of the above malfunctions are classified as non-serious and can be easily fixed on your own, without contacting a service center. But, along with simple breakdowns, there are also more complex ones; it’s worth saying a few words about them.

Serious damage to the microwave oven

Malfunctions that are difficult to eliminate on your own include those that require certain knowledge from the adjuster and that only professionals or those who are well versed in household appliances can fix. However, despite the difficulty of eliminating them, you should still try to set up a stove at home. The main thing is to act carefully so as not to further damage the device.

Serious microwave oven malfunctions include:

Breakdown of the timer or control panel usually occurs due to the long service life of the device or careless handling of it.
For inverter stoves, there is a breakdown of the inverter, which is responsible for the economical consumption of electricity by the appliance. Quite a common failure.
Transformer failure is a breakdown typical of simple microwave ovens.
Failure of an electromagnetic lamp occurs in ovens of any type.
Failure of the magnetron, which is directly responsible for the operation of the entire microwave oven.

Having identified the cause of the microwave malfunction, you can begin to repair it, and the following tips may be useful to you.

Why does a microwave oven spark during operation: reasons, solutions

Most often, the cause of such a malfunction is user inattention. Turning on a device with an empty platform, metal objects in a working device, drops of dried fat on a mica plate - this is what can cause such a nuisance.

Even utensils with gold or silver rims cannot be used for microwave heating, let alone stainless steel or enameled steel utensils. Let's look at the causes of sparks and methods for eliminating them.

Microwave oven malfunctions causing cracking noises and sparks

A mica plate, if it is not promptly cleaned of any grease that has fallen on it, begins to deteriorate over time. This happens due to the heating of food debris accumulated on it. As a result, a small black speck appears on the mica plate (microwave diffuser), which quickly grows during operation of the microwave oven. The process is accompanied by smoke, sparks, and crackling sounds. Consequences of burning a mica plate (microwave diffuser)

Crackling and sparks inside the microwave: what to do, how to troubleshoot

The first step is to thoroughly clean the inside of the microwave oven. To replace it, it is better to purchase a larger plate. Having attached the old one to it, we cut out the required shape with ordinary scissors, and sand the edges with sandpaper. Next, we mark and drill holes for the mounting screws, after which all that remains is to fix the cut plate with self-tapping screws. Mark the outline of the old plate with a pencil and cut out a new one

IMPORTANT INFORMATION! After removing the mica plate, pay attention to the condition of the magnetron cap. If necessary, it should also be replaced. Another cause of crackling and sparks can be peeling of the camera enamel. This happens when too large dishes are placed in the oven to heat up. It rubs against the walls, leaving scratches that lead to sparks and can easily damage the magnetron. If scratches appear, perform the following actions.

Thoroughly wash the chamber to remove dried fat.
Clean the scratches with sandpaper and degrease.
We apply a primer, and then 2-3 layers of enamel (food grade, fireproof or electrically conductive).
We wait for it to dry completely, after which the device can be used.

This kind of microwave oven cannot be used - it requires restoration and replacement of the mica plate, which is already starting to burn out.

Why does the microwave heat up so much?

This is due to insufficient cooling of the device. Either there is something wrong with the fan, or the device is not installed correctly. Rearrange the microwave according to the instruction manual.

If you are unsure of your abilities, it is better not to start repairs at all.

If this does not help, in the most harmless case the fan is simply clogged, grease and dirt have stuck to it in a thick layer and do not allow it to rotate normally. The fan relay may also be broken. It turns on and off whenever it wants, does not rotate as quickly as it should, and as a result the case begins to heat up. You need to call a specialist. You can't do anything here without special skills.

The essence of self-repair is only to replace broken parts with new ones. You won’t be able to repair the parts yourself without experience.

Advice. If you doubt that you will be able to identify and fix the problem yourself, it is better not to risk it and immediately take the microwave oven for repair. Spend a little money, but you will save your nerves and the device itself. If something happens to him during the service, there will be someone to demand compensation from.

A win-win option is to call a specialist. He will always accurately, quickly and without problems determine what exactly the breakdown is.

The microwave is humming: check the capacitor

Replacing capacitors and resoldering contacts is quite feasible at home. However, if all of the above has been replaced and is working properly, contact a professional.

If the microwave has stopped heating food properly and is making an uncharacteristic hum, then the reason may be the following:

Diode failure. Its task is to direct the current in one direction. If a part fails, the microwave begins to buzz and the food does not heat.
A faulty capacitor causes waves to appear and the device hums.
Failure of the magnetron can cause buzzing and humming.

High voltage diode

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

If the microwave hums when turned on, it is possible that the capacitor has failed. It's easy to check: connect an ohmmeter and monitor the readings. If the arrow moves, then the capacitor is working; if not, then it is the cause of the breakdown. Please note that replacement or testing occurs only on a charged capacitor.

Magnetron

If all the parts show themselves to be operational, then most likely the problem is in the magnetron. A sign of malfunction is the humming of the microwave when there is no heating. Conduct a visual check for cracks and carbon deposits, measure the values with an ohmmeter. If it is damaged, replace it with one of similar parameters and dimensions.

You decide to heat up a dish, the microwave works, but the temperature of the food does not rise. The reason can be either simple or complex. If the voltage is low, you need to install a stabilizer to correct the situation. Once you determine why the microwave is not heating food, you need to start repairing it.

Even old wiring can explain why the microwave stopped heating and defrosting food. Don't forget about preventive measures. It is extremely important to regularly clean the heat chamber from splashes of grease and food debris. To avoid unpleasant odors, use plastic lids and hoods.

Microwave works but doesn't heat well? Troubleshooting methods:

Incorrectly marked mode - use the instructions to set the desired command (“warm-up”); turn on the oven for a while and make sure that the food is heating up - the problem is solved.
Insufficient voltage - take care to install an uninterruptible power supply.
Problems with the normal functioning of the door - replace parts.

If the microwave oven is no longer in good working order and cannot cope with direct tasks, first refer to the instructions, which contain a list of tips and valuable recommendations on why the oven fails. If you don't find a useful answer, check an item such as voltage. If everything is in order, unplug the oven and check other elements - microswitches.

There are a number of reasons why the microwave stopped heating and it’s not a matter of broken parts, for example:

The network voltage has decreased. The operation of the microwave oven, as well as its heating, can be affected by slight decreases of 20V. As a result, the plate will be heated, but there will be no food in the middle of the vessel. The issue of power outages can be resolved in one day: you just need to go to the store and buy a power supply.
The network is overloaded. If two powerful appliances are running from the same outlet at the same time, an overload occurs. This issue can be resolved by installing another outlet.
The door is out of order. As a result of a broken latch, the door does not close tightly and the microwave does not heat food or heats it poorly. Here you can try to repair or completely replace the latches.
Incorrect mode selection. Very often, after defrosting mode, they forget to switch back to microwaves. Defrosting does not heat the food to the required temperature, and you are already about to disassemble the appliance.

We suggest you familiarize yourself with the Products that will help you remove nail polish from clothes.
Often, the microwave works, but does not heat the food due to the fact that the magnetron is out of order. Next on the list will be a capacitor, a fuse, and a transformer also often breaks. The reason for poorly reheated food may be the following:

the timer or the control unit itself is broken;
due to breakdown of the transformer and other parts;
The inverter may be faulty (this only applies to inverter microwaves).

If you find that the microwave oven turns on but does not heat and makes an unusual sound (for example, buzzing), there are 3 explanations for this:

The diode has become unusable. This part does not allow current to pass in the opposite direction; the current moves only in one direction. If this part fails, the appliance begins to buzz and does not heat the food;
it's time to change the capacitor. A capacitor failure leads to the generation of waves and the device hums;
magnetron failure. A defect in this part may also cause a buzzing or humming noise.

If you nevertheless decide to repair the microwave oven yourself, then before watching anything, turn off the device from the network. Be sure to find the instructions, which contain the names of all the parts that are there.

First of all, after removing the cover, you need to make sure that all fuses are working properly. If you see that they have turned black or the thread has burned out, then you just need to replace them. Often there are two fuse parts inside.

When buying a new part, be sure to take the old (burnt out) one. To temporarily solve the situation, it is not recommended to make bugs out of wire. There is a great danger of fire, and the price of a good fuse is no more than 50 rubles.

If the device hums when turned on, there is a possibility that the capacitor has broken. It’s easy to check its serviceability: you need to take an ohmmeter and connect it to the part. If everything is in order, then the ohmmeter needle moves. And if it stops, then the capacitor has failed, and because of this the stove is noisy.

If you notice a burning smell or something crackling inside while the microwave is operating, after watching this video you will understand what’s wrong. It shows how you can repair a microwave oven if it sparks.

There may be several reasons why a microwave oven does not heat well or does not heat at all:

low voltage in the network (less than 200 V like the LG MS-2021U microwave oven);
malfunction of power circuits (magnetron, high-voltage transformer, diode and fuse, capacitor);
problems in the control circuit, the culprits of which are the timer or the control unit. A common problem with a Samsung microwave oven;
If an inverter microwave oven does not heat, the reason may be due to inverter dysfunction.

In turn, the following phenomena may be the causes of magnetron failure:

a metal object entering the chamber during microwave operation;
natural wear and tear (Electrolux built-in microwave ovens often suffer from this, as they break down very quickly);
Operating a microwave oven idle leads to sparking, which damages the magnetron.

If the Samsung microwave has stopped heating, and when turned on it makes a buzzing or buzzing sound, the problem may be a failure of the high-voltage diode. The normal operation of this electronic element is to allow electrical current to flow in one direction and block it from flowing in the opposite direction. An example of this is the LG MS-2041U microwave oven.

Another culprit for the lack of heating of the microwave oven is a high-voltage capacitor, the operation of which is aimed at accumulating an electric field. If this element fails, then the process of generating microwaves will not occur. A characteristic hum or buzzing sound will come from the camera.

The process of checking and replacing a high-voltage capacitor requires its preliminary discharge, which is mandatory. This is especially true for the LG MS-2042 microwave oven.

Trying to troubleshoot problems yourself is not worth it, since ordinary consumers do not have sufficient knowledge and the necessary tools to carry out diagnostic and repair work correctly.

Along with replacing the faulty part, a good technician will also carry out preventive maintenance so that the microwave will serve you for a very long time.

The technician's visit is paid depending on the distance of the service center from the customer's home - 10 - 20 USD. e. By the way, the Samsung G2739NR microwave oven costs the same amount.

The simple process of replacing parts costs 20 USD. e. And the Samsung MS23F302TAS microwave oven costs about the same.

The cost of parts that may be needed for repairs ranges from $2 to $20. For the same amount you can repair a Panasonic microwave oven.

Multiplier check

The multiplier consists of a diode and a capacitor. The condition of the capacitor is checked with an ohmmeter, although it is intended for use in alternating voltage circuits. If the instrument needle first deviates a little and then shows infinity, everything is fine. The presence of slight resistance indicates a breakdown. If there is an internal break, the needle remains at zero. A malfunction of this capacitor often causes the microwave to hum but not heat. Since it is difficult to check the diode at home, it is better to immediately replace it with a known good one.

Other possible malfunctions: causes, solutions

It happens that heating is produced, the light inside the chamber lights up, but the platform does not rotate. The reasons for this may be:

incorrect installation of the plate;
broken drive gears;
engine failure;
bad contacts.

The problem with the plate is easily solved - you just need to fix it. If this is not the reason, you will have to disassemble the device. Failure of gear gears is a problem that occurs more often in new models of microwave ovens.

In pursuit of reducing the cost of the product, the manufacturer began installing short-lived plastic gears (older models had metal ones). If this is the reason, then the sore is treated by replacing the gearbox - restoring the gear teeth is unrealistic. The plate must fit neatly into the grooves. The gear motor that rotates the tray may fail under the influence of power surges. In this case, one of the stator windings burns out. The result is motor failure.

Previously, engines could be sent in for repairs. They were rewound and they could function again. Today, such workshops no longer exist: in the event of such a breakdown, you will have to buy and install a new one. The main thing is to clearly and correctly rewrite the markings. Otherwise, the engine simply will not fit your model. The solution to the problem of bad contacts is quite simple. All connections must be cleaned of oxide, if necessary, tightened and connected in the reverse order.

What to do if the microwave oven does not turn on at all

If the microwave does not turn on, the reasons should be sought in the 220 V socket, plug, wire or fuse. The socket is checked, the wire and fuse are checked using a multimeter. The faulty part is replaced with a new one. If you think about it, this is the simplest problem that can happen to your microwave oven. A blown microwave oven fuse needs to be replaced.

Fault Detection

If you still have questions about how exactly to find a breakdown, you can follow the following instructions:

Measure the voltage of the outlet to which the microwave is connected - even minor deviations can greatly affect the operation of the equipment.
Check the operation of the door latches.
For a de-energized microwave, remove the top cover to gain access to the internal parts. If repairs are required, remove the back cover.
Check fuses visually. Burnt specimens are immediately visible - they are swollen and black. If there are no such traces, then you need to check the resistance with a tester.
Check the voltage in the capacitor and diodes with an ohmmeter.
After the microwave has completely cooled down, visually check the magnetron and its contacts. If there are no external problems, then it is worth assessing the resistance of the threads.