Microwave stopped heating: causes, repair methods and expert advice

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Microwave stopped heating: causes, repair methods and expert advice
Microwave stopped heating: causes, repair methods and expert advice

Today, almost every kitchen has such a useful assistant, without which it is already difficult to imagine how you can quickly heat up food. We're talking, of course, about the microwave oven. Probably everyone in their hearts wishes the one who invented it all the best. But, like any other technique, a microwave oven can be capricious. That's why, for example, the microwave stopped heating? The reasons for this behavior are sometimes puzzling - after all, everything works, glows and spins as it should, but the food remains cold.

A useful helper in any kitchen

In this case, the first thing that comes to mind is to take the equipment to a repair shop, where they will take care of it. However, it is not necessary to go to the nearest service center or call the master at home - you can try to diagnose and fix the breakdown yourself.

Microwave oven operation

To understand why the microwave suddenly became stubborn, you should understand how it works and works. At least in general terms. The most important part of the device is the magnetron. It is he who produces microwaves, which heat food. All products contain a certain number of liquid molecules (somewhere there are more, somewhere less).

Microwaves make them move, and as a result, friction occurs - the food is heated. As you can understand, this happens differently than under the influence of a heating element - there the heating occurs due to the outgoing heat. Thanks to this device, you can not only reheat food, but also defrost it.

Operating violation

If suddenly the LG microwave stopped heating, the reason may lie in your own stubbornness. And everything seems to turn on, it works, but after some time the delivered food still remains cold. In some cases, this may occur due to non-compliance with elementary operating rules.

Microwave stopped heating

After all, few people usually look into the instructions and everyone learns the features of the device using the scientific poke method. This approach is fundamentally wrong, and often the following factors are the causes of violations:

  • Insufficient voltage - the line can be overloaded if several high power devices are connected to it. And if the voltage drops by 5-10 V, the microwave will not heat. In this case, it is necessary to lay a separate line.
  • Voltage fluctuations are the main reason for the failure of expensivedetails. It is recommended to purchase a stabilizer to protect equipment. It is optimal to connect it immediately at the entrance to a house or apartment - then all electrical appliances will be under reliable protection. In extreme cases, you can get by with a small device - individually for a microwave oven.
  • Problems with the door are another reason why the microwave has stopped heating. If it has become worse to close, then the food will be poorly warmed up or remain cold. In this case, it is enough to change the latches with the magnetron, and the problem will be solved.
  • Mode of operation - sometimes the reason for the malfunction of the microwave oven is so banal that you simply wonder. And the point is in the wrong choice of operating mode. For example, after defrosting, the mode was not set back to microwave.
  • Metal items - A fork or knife left in food causes sparks and the food itself does not heat up.

The above situations are mild, and with attention the problem is solved quickly. You don't even need to contact the master. In extreme cases, this is another reason to still look into the instructions, which usually describe what can be done in certain situations.

The microwave has stopped heating, but it works - what to do?

In some cases, appliances from well-known brands Samsung, Supra, Panasonic and other manufacturers, instead of heating food, start to buzz.

Microwave stopped heating but works

The first step is to understand the reasons for thisphenomena:

  • Diode failure. The duty of this part is to prevent the current from flowing in the opposite direction.
  • Faulty capacitor that needs to be replaced.
  • Due to the failure of the magnetron, you can hear not only a buzz, but also a buzz.

If you decide to look for a malfunction yourself, then you should consider that the microwave oven is one of the most dangerous household appliances. The threat is that the magnetron needs a voltage of the order of 4-5 kV to operate. At the same time, it is stored in the capacitors for some time after the device is turned off.

Therefore, the risk of electric shock to an inexperienced electrician is high. Therefore, if you are not sure, it is better to entrust all the work to a specialist.

Dishes are heating, not food

If the Samsung microwave has stopped heating, but it works, then the reason for this may be the wrong choice of dishes. The optimal material is transparent heat-resistant glass, ceramics, porcelain, faience. Plastic is convenient to use, but not every type is suitable for a microwave oven, and actually for the food itself.

There are varieties that should never be used to heat food in the microwave. We are talking about plastic with the appropriate marking:

  • PVC, or polyvinyl chloride;
  • PS, or polystyrene.

Labeled plastic containers approved for microwave use:

  • P - polyamide.
  • PP - polypropylene.
  • Thermoplastic.
  • Duroplast.

The last two options -these are containers that do not deform when heated and are able to withstand strong heat up to 100 ° C or more. And unlike glass containers, plastic is not afraid of temperature changes.

Serious reasons

All of the above are simple reasons why the microwave does not heat food. At the same time, it should be noted that the rotation of the tray with dishes, lighting and other signs of the operation of the device do not always depend on the internal structure of the device. In other words, if the Samsung microwave oven has stopped heating, the reason may be the failure of only some part of the entire equipment.

Problems with the microwave oven

And outwardly the microwave oven will look efficient. And in addition to simple situations, there may be serious cases that sometimes require prompt and qualified intervention from outside.

Maybe it's the magnetron?

This device is worth dwelling on in more detail. A common reason why the microwave suddenly does not heat food is poor contact. Wires coming from the transformer are connected to the magnetron connector terminals. And high voltage flows through them, so the tips must be removed with difficulty. The reason for poor contact, in turn, lies in the heating, due to which it weakens. You can correct the situation by crimping the contacts with pliers or pliers.

In some cases, the reason that the microwave has stopped heating, but it works, is damage to the cap of the magnetron antenna. If it just turned black, no holes, then it should be goodclean its surface with fine-grained sandpaper. It should become shiny, even and smooth, like a mirror. This is the only way to achieve maximum effect. But you should not be zealous either, rubbing the metal to holes. In conclusion, it remains to remove all the dust.

Magnetron Replacement

If the cap is still melted, you should first make sure that the device itself is working. To do this, you need to remove the "cover" and inspect what is under it:

  • The metal is intact - in this case, just change the cap.
  • The metal is damaged, which means that the magnetron itself needs to be replaced.

What to do if the microwave stops heating? If it is necessary to replace the magnetron, it is worth weighing everything well - its cost is quite high. For this reason, it is more rational to purchase a new microwave oven.

But if the microwave is still more expensive, then it makes sense to change the magnetron itself. Only here it is necessary to take into account all its parameters, because they are all different from each other. It is optimal to take a faulty device with you to the store, where the seller will select an option with all the necessary characteristics. Only in this case the magnetron will fall into its rightful place without problems.

Cap Trick

What can replace the magnetron cap if the device itself remains intact? It is not easy to find it on sale, because it costs mere pennies, which is unprofitable from an economic point of view. An option is to carve a cap on a lathe, but it is not suitable for everyone. After all, not everyone in the house has such equipment, and not everyone has familiar turners.yes.

Could it be the magnetron?

Another option is more acceptable - an old electrolytic capacitor of the right size. They select a part of a suitable diameter, cut off the necessary piece of the body and carefully make a hole in the center. When drilling the body, high precision must be observed - the size match must be perfect!

Then it remains to clean the resulting cap to a shine with sandpaper with the finest grain and polish. The conductivity of this part affects the quality of the microwave oven. At the end, the cap is put in place and the device is checked for performance.

The role of the fuse

When the microwave stops heating, the cause may be a faulty fuse. This element is present in almost all devices. The fuse plays a very important role (this can be understood from the name) in protecting against harmful factors:

  • short circuit;
  • voltage fluctuations.

There are a lot of types of fuses, microwave ovens, as a rule, are equipped with parts that have a fusible insert in the form of a thin metal thread. It is placed in a glass flask and closed with metal caps at both ends (actually, these are fuse contacts).

The principle of action is easy to understand - the thread is heated to the melting temperature of the metal and is destroyed only when too much current passes through it. Accordingly, the device is de-energized. In this case, the limiting value of the current passing through the thread, without harm to it, depends on the characteristics(including section) of the metal from which it is made.

Where is the part located?

If the microwave has stopped heating due to a faulty fuse, you should know where it is located. Usually, manufacturers put several parts in their devices, but this is not always the case. One of them is a network one and is located on the corresponding board. This fuse is rated for current in the range of 8 to 10 amps, but it is not able to protect electronic parts from power surges. However, a short circuit can certainly be avoided.

Microwave fuses

The high-voltage fuse is able to protect the transformer from overcurrent and is placed near it. At the same time, the part is placed in a plastic casing for its additional protection.

If the microwave oven has an electronic control, then in such models there is another fuse - in close proximity to the rectifier, which is responsible for converting alternating current to direct current with a voltage of no more than 5 volts. It is this power that is needed for microcircuit elements.

If the microwave has stopped heating due to a faulty fuse, then the procedure for replacing it is noticeably more complicated. The fact is that for most models with electronic control, the part is located in an inconvenient place (at the top of the primary winding of the transformer and in the insulation).

But there are pleasant exceptions - everything is much easier with Samsung microwaves, since the fuse is located on the control board.


It is easy to detect a malfunction - a burnt thread will be detected by the naked eye. In this case, the part needs to be replaced. It is also worth doing if blackening of the glass bulb is visible.

It is worth noting that some models may not have high-voltage fuses - their function is assigned to the network part. And in order to understand which fuses are installed in a particular model of microwave oven, you should refer to the instruction manual.

Checking other details

Sometimes, when the microwave has stopped heating, the cause may be caused by other components, which also make sense to check. The problem may be with the capacitor. To do this, it is worth connecting it to an ohmmeter with an arrow - if it moves, then the part is working, and the reason should be looked for elsewhere. Otherwise, the culprit has already been found.

Checking a diode is a rather complicated procedure, and for this reason even masters prefer to simply replace it right away. Its cost is not high, so there will be no special losses, even if it turns out to be intact. The main thing is to pay attention to the parameters when buying a new part - they must completely match the old diode.

Microwave oven device

You should also check the capacitor. Even if the microwave itself works - everything turns on, spins, buzzes, but the food does not heat up, it is likely that the problem lies in it. To do this, you should take the tester and set the resistance measurement mode on it. If the measurement reveals a break or a smallresistance, therefore, the reason why the microwave stopped heating has been found, and the part needs to be replaced. In the case when the value tends to infinity, then the capacitor is working.

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