What is the reason why the microwave works, but does not heat up and what to do
Misuse and internal failures of the microwave oven will cause it to malfunction. It is important to quickly determine the reason why the microwave is working, but not heating, in order to solve the problem.
Major violations of the operating rules
The most common cause of microwave failure is neglect of the rules of use.In order to avoid the occurrence of microwave malfunctions, you should carefully read the instructions for use.
Metallic object in the room
The process of heating food is due to exposure to microwaves. The presence of a metallic object inside the microwave chamber causes the waves to reflect off the walls of the metal. As a result, there is a devastating effect on the functionality of the equipment.
Wrong dishes
For use in a microwave oven, it is recommended to purchase special dishes that do not heat up and do not affect the taste characteristics of food. You can also check the existing dishes by placing them in the chamber, placing a glass of water next to it and turning on the heating at maximum power. If the container does not heat up after one minute, it can be reused in the microwave.
Use a blank camera
The operation of an unloaded microwave leads to the fact that the waves generated do not encounter obstacles and are constantly reflected by the internal walls until the timer is triggered. Concentrated radiant energy adversely affects major equipment components, leading to microwave failure.
microwave appliance
To make it easier to find the cause of the malfunction, you need to understand the device of the microwave oven. Each of the components of the microwave has its own purpose and works in conjunction with the rest of the details.
lighting lamp
The microwave light comes on when the food heats up and makes the operation more comfortable. In the event of a fault, the LED starts flashing or does not light up at all. It is allowed to use a microwave oven without a backlight, but for convenience it is worth understanding the cause of the breakdown and, if necessary, replacing the light bulb.
Vent holes
Modern microwave ovens are equipped with a fan that circulates hot air through the working chamber. The air movement speeds up the heating and cooking process. Part of the air mass exits through special holes that can be placed in the back, bottom or sides of the microwave.
Magnetron
A microwave magnetron is a microwave generator. The waves generated by the magnetron heat the food by setting the water molecules in motion. In this way, the food warms up without external heat influences. In this regard, the microwave temperature indicator can not exceed 100 degrees - the boiling level of the liquid.
Antenna
An antenna is installed in the equipment for the directional effect of the waves emitted by the magnetron. Incorrect operation of the microwave antenna leads to chaotic radiation. As a result, the microwave oven works, but the food does not heat up or heats up very slowly and unevenly.
Waveguide
The purpose of the waveguide in technology is to match the magnetron with the working chamber and distribute the emitted waves. Externally, the waveguide is a hollow metal tube of rectangular section. The waveguide entrance is located outside the chamber and is equipped with a flat piece for fixing the magnetron. The second waveguide base is located inside the chamber and covered with a cover.
Capacitor
The need for a capacitor in a microwave oven is due to the equalization of overvoltages that occur in the network during operation. The capacitor consists of two insulated conductors enclosed in a metal case.After the technique starts, the conductors interact in a circuit, resulting in a build-up of electricity. If there is not enough mains voltage for the microwave to operate properly, the stored energy is released, helping to prevent a sudden power surge.
Transformer
Externally, a microwave transformer looks like a block with coils. The windings wrap around the magnetic circuit and convert the incoming energy. When heat is released, the transformers act as a sort of power source for the magnetrons. The generated power reaches 1500-2000 watts, which after conversion drops to 500-800 watts.
The transformer is made up of several windings:
- a voltage of 220 V is supplied to the primary;
- the secondary windings reduce the alternating voltage;
- the next winding is needed to create a constant voltage.
drive unit
The rotary motor of the microwave oven is responsible for rotating the pan on which the container with the food is placed. A malfunction of the component leads to the fact that the paddle does not rotate and the waves do not affect the food correctly. The result is gentle heating.
Control Panel
The touch or mechanical control panel of microwave ovens, according to the principle of operation, is a microcomputer. The standard panel allows selection of heating power and operating time. Modern models of microwave ovens are equipped with an expanded control panel with additional functionality, for example, the choice of the type of heating depending on the food placed inside.
Rotating pallet
The turntable, which rotates during oven operation, is an integral part of any type of microwave oven. Rotation ensures food is heated evenly.
roller separator
A cage equipped with rollers is necessary to drive the pallet. After the microwave starts, the central part of the separator begins to rotate, due to which the rollers roll in a circle and rotate the pallet.
door latch
Due to the presence of a latch, the microwave door closes tightly. To open the door, you need to press the button, which is usually located under the control panel at the bottom of the microwave.
Simple reasons
There are many reasons why a microwave oven works normally but does not heat food. Most often, these are simple reasons associated with improper use of the microwave or third-party factors.
Low mains voltage
If the microwave does not heat the food well, while the backlight lights up inside and the pan is spinning, you need to check the voltage level of the network. The operation of the equipment directly depends on the voltage, and if it drops below the 205 V mark, incorrect heating is observed.You can use a voltmeter or universal tester to check the mains voltage.
In the absence of specialized devices, it is possible to assess the degree of tension by the low brightness of the glow of the incandescent lamp.
Simultaneous activation with other powerful devices
When multiple devices that consume a large amount of power operate at the same time, poor power distribution or voltage drops may occur.
There is no contact in the socket or the cord is damaged
Lack of contact in the socket or mechanical damage to the cord leads to the fact that the required amount of voltage is not supplied to the microwave. Other devices can be plugged into the outlet to verify that the outlet is working.If they are working properly, there is voltage in the socket. Damage to the microwave cord on the outside can be seen during visual inspection, and internal faults can only be detected during diagnosis. Replacing or repairing the cord helps solve the problem.
Broken door locks
The latch door of the microwave oven closes tightly, as it serves as a protective screen and protects against negative radiation. The latch of the lock is a safety device against the operation of the equipment in the open state. In order for the lock to work, you need to push the door and press it more firmly against the body. If a part is broken, it must be repaired or replaced before using the microwave oven.
Wrong mode selection
On modern types of microwave ovens, several modes of heating and cooking are offered. Choosing the wrong mode often results in food cooking very slowly. Also, if a problem occurs, it is worth checking the selected power level.
Incorrect countdown
Due to an incorrect countdown, the timer runs faster than the set time period and stops the microwave earlier. Therefore, to heat food, you will have to turn on the oven several times in a row or specifically set the timer for a longer period.
Inverter malfunction
In inverter types of ovens, the presence of an inverter helps to save energy. In the event of a malfunction, the element significantly reduces the amount of energy consumed, so there is not enough energy to heat food.
To repair the inverter, you will need to partially disassemble the equipment.To carry out repair work, it is recommended to contact a specialized service.
Aging Magnetron
The duration of the normal operation of the magnetron in continuous operation is generally 5-7 years. In operation, the magnetron cathode gradually loses its ability to emit a sufficient quantity of electrons. As a result, the power of the microwaves generated decreases and over time they become insufficient to heat the food. The emission of the microwave magnetron can be restored, but in practice this is rarely done due to the need for additional equipment. To eliminate the malfunction, it is easier to replace the magnetron yourself or contact a specialist .
serious reasons
More serious causes require professional intervention. This list of reasons is associated with improper operation or failure of the internal components of the microwave.
Fuse
The fuse protects the oven from the effects of overvoltages. Unstable voltage in the network can cause burnout of the electronic components of the equipment. Before electricity is supplied to the internal mechanism, it passes through the fuse bulb with a metal wire.
If the voltage exceeds the nominal value, the filament burns out and protects the microwaves by breaking the circuit.
Magnetron problems
Due to the peculiarities of the magnetron device, it is not the whole part that fails, but individual components. To restore the working capacity of the magnetron, you need to carry out diagnostics and find out the exact type of breakdown.
Weak contacts
The simplest type of magnetron malfunction is weak contacts. At the terminals of the magnetron there are wires of the filament winding of the transformer, and due to heating the contact may weaken.To improve the contact, you can additionally crimp the wires with pliers.
Damaged antenna cap
One of the main components of the magnetron is the antenna cap, which maintains the vacuum. If the surface of the cap becomes dark and a drop of solidified metal appears on it, you need to clean the part with fine-grain emery paper. The surface should be flat, smooth and shiny. After the work is completed, you must remove all dust and metal residues.
Replacement
If the repair did not give the correct result, or if the plug melts, it is necessary to make sure that the magnetron is in good condition and that the vacuum is maintained. For this purpose, you need to remove the cap and inspect. If the metal sheath remains intact, the cap will need to be replaced. If the integrity of the metal is violated, you need to install a new magnetron or buy a new microwave oven, having previously compared the costs and chosen the most suitable option.
How to make a capacitor with your own hands
You can make a new antenna cap yourself to replace the faulty one from a capacitor. To do so, follow these steps:
- Take a piece of the correct dimensions, cut out a part of the body and drill a hole in the central part.
- Sand the body with fine grit emery cloth and buff to improve the conductivity of the cap.
- Secure the cap in place and check for proper operation.
Mica Plate Problems
A malfunction of the mica plate leads to the fact that during operation of the microwave it crackles and sparks. If you notice a defect in the work, you must carefully clean the buffer and the waveguide. In case of serious mechanical damage to the plate, including the formation of burnt holes, you need to replace the microwave components.
Burned capacitor or faulty diode
If the microwave oven works, but at the same time emits extraneous sounds and does not heat the food, a possible cause may be a breakdown of the capacitor or the diode. To check, you need to check the performance of the capacitor using a tester by starting the resistance measurement mode. When during measurement the tester shows an open circuit, it means that the capacitor is inoperative and with a low level of resistance, damage to the element is likely. In either case, the capacitor cannot be repaired and must be replaced. Only if the tester demonstrates the maximum resistance indicator does it mean that it is in good working order.
Checking the condition of a high voltage diode is more complicated than checking a capacitor. For this reason, it is much easier to replace the diode right away, since the low cost allows it without too many problems. When considering installing a new diode, it is important that the purchased replacement part matches the characteristics of the replaced part.
Multiplier issues
The combination of a diode and a capacitor forms a voltage multiplier and a voltage rectifier in microwaves. The voltage supplied by the anode winding of the transformer and the voltage removed from the capacitor are combined and at the output of the multiplier a double voltage of negative polarity is obtained. Malfunctions of the microwave multiplier will cause power surges, which will prevent the equipment from generating proper waves and heating the food in the chamber.
Control unit malfunctions
When diagnosing the equipment, you need to check the status of the control unit.To do this, remove the control board and examine it with a magnifying glass for the slightest defects. A large number of board types are equipped with an additional fuse, which burns out as a result of prolonged operation. This problem is often encountered in equipment manufactured by Samsung.
Signs of a malfunction of the microwave control unit are: traces of swelling of the capacitors, a change in the initial state of the tracks, visible defects of the Zener diodes and diodes. Since each type of equipment differs in the type of board, the nuances of the repair are individual for each specific case.
Design features
When diagnosing the condition of a microwave oven and planning the repair or replacement of individual components, you must 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 oven only with certain knowledge.
LG
LG's modern microwaves are equipped with L-Wawe technology, thanks to which the waves generated propagate in a spiral and ensure a more uniform and deeper penetration of heat in all parts of the dish. The special design of the inner surface of the case 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, can be easily cleaned of contamination and has increased resistance to damage.Due to the low thermal conductivity of bioceramics, heat loss is reduced and the process of cooking and heating food is accelerated.
"Bork"
New models of Bork microwave ovens offer a variety of programs that allow you to defrost food, carry out rapid heating and cook food in different modes. A more complex control system often creates problems when trying to fix the equipment yourself. Faced with a malfunction of the electronic components of the Bork microwave oven, you need to seek help from specialists.
Daewoo
Microwave manufacturer Daewoo occupies 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 pizzas and pancakes. In this variety, you can cook 2 dishes at the same time. The downside is the complexity of the internal components, which makes it more expensive to repair and replace components.
"Sharp"
Sharp manufactures ovens with basic configurations that do not have any special features. Modern varieties are equipped with touch screens and displays.
panasonic
Panasonic brand microwaves are distinguished by a lot of additional cooking and heating programs. A complex design control system in the event of a breakdown of an electronic component requires professional repair.
Elenberg
Elenberg products are built with a basic internal configuration to facilitate component repair. In the event of a breakdown of more modern varieties with a touch screen, it is worth contacting a service center.
How to extend the life
In order to use the microwave for a long time and not encounter problems when heating food, you must follow the instructions for use. It is forbidden to use unsuitable dishes, to leave foreign objects inside the chamber.