The microwave stopped heating the food: what should I do?
In the morning I went to work without breakfast, because I do not like to eat cold dumplings. It turned out that my microwave does not heat, but it works. When I woke up, I put dumplings on it on the plate, turned it on for 3 minutes and ran to the bathroom. After finishing the procedures and getting dressed for work, I got them out, but could not eat - they were like pieces of ice. It turns out that the device turns on, hums slightly, turns them on a tray and lights, but does not heat up at all! Why did this happen?
- 1Possible reasons why the microwave stopped heating
2How to find a malfunction
- 3Video about possible causes of breakdowns
Possible reasons why the microwave stopped heating
- insufficient network voltage;
- the miniature microwave oven door switch does not work;
- the mains fuse has blown;
- high-voltage fuse in the casing;
- the fuse on the transformer is faulty;
- a doubler fault - a diode;
- breakdown of the doubler - capacitor;
- the transformer does not apply voltage to the control panel;
- faulty pass-through capacitor;
- does not heat the electromagnetic lamp - magnetron.
How to find a malfunction
It is necessary to read the instruction, how the microwave oven works, in particular the last points about possible problems with it. In the instruction you can find the answer to the question what to do in this case. If there are no papers left, we turn to self-diagnosis.
First you need to measure the voltage of the network. Even with a small (5-10v) deviation from 220v, the technician will not warm as expected.
Next, you must disconnect the device. Check by an ohmmeter how the miniature switch on the door of the oven switches on. Then remove the top cover by unscrewing the screws.
Then you need to check the mains fuse. If visually there is no burnt wire inside and the fuse is not black, just in case, to be sure, we test the resistance of the tester. Then it is necessary to check the high-voltage fuse in the housing with an ohmmeter, it will show little resistance - it's not so bad. Check visually and the tester fuse on the transformer - normal or not.
Then start to check the components of the multiplier - the diode and the capacitor. With an ohmmeter, you can check the serviceability of the capacitor, although it is designed for operation in AC networks. The arrow of the tester has deviated and gone into infinity? This means the capacitor first took a small charge of direct current from the tester, everything works.
If the condenser is faulty, the arrow does not deviate - the contact breaks. If it shows little resistance at once, it's bad, it's broken. Then you need to change the diode to a new one, so as not to mess with the check.
Then it is necessary to check the passing capacitors of the filter on the housing of the electromagnetic lamp. Before testing, they must be discharged by an electrical screwdriver with an insulated handle, alternately closing the terminals to the housing. One ohmmeter probe is placed on the output of the container, the second - on the metal casing.
If the device does not show zero resistance, this is normal, but if the ohmmeter scale is zero, change the part. Then, with an ohmmeter, we check the contacts of the tank for breakdown. Between them, the normal resistance should be about, Ohm.
We check the primary winding of the transformer with a tester. When the device is turned on, the voltage on it with the heating on should be 220v.
This is a powerful lamp, it itself generates electromagnetic waves of a certain frequency (-10 GHz) in the interaction of the electron flux with the magnetic field. But do not rush to conclusions about the malfunction, you still need to visually check the reliability of soldering the contacts induction filter coils and the integrity of the connection of the magnetron supply terminals to the gate capacitors.
If the cause is in the detached contact or oxidized terminals, then to solve such a problem is very simple itself.
Further, we test the resistance of the magnetron filament by the tester, it should be of the order of 2-3 ohms. But if everything is checked and everything seems to work normally, then the lamp itself is spoiled, that is, it does not turn on.We do not recommend trying to understand its device for repair purposes.
Attention! The temperature of the metal housing and the radiator of the operating lamp is more than 150 degrees! Wait for the device to cool down gradually before touching it with your hands. Then you can not do anything yourself.
It will be much easier to write down all its technical characteristics: power, cathode voltage, current and voltage of the filament, anode current. Order a new device in the warranty workshop, purchase and replace. You can do all the repair work yourself, but it's better to call a qualified repairman.