Reasons and maintenance methods for the non heating of induction cookers

The reason why the induction cooker is not hot:

The fault phenomena of induction cookers can be roughly summarized as follows:

1、 The induction cooker does not respond when powered on (not powered on).

The causes of such faults usually exist in the following circuit units: high-voltage main circuit, low-voltage power supply circuit, and microcontroller circuit.

2、 The induction cooker cannot be turned on.

When such faults occur, the first step is to eliminate adverse factors caused by the usage environment, such as grid voltage, ambient temperature, etc. When it is determined that there is a malfunction in the induction cooker, focus on checking the protective circuit. Pot temperature detection circuit, IGBT temperature detection circuit, grid voltage detection circuit, button circuit.

3、 The induction cooker can be turned on with an alarm signal, but it does not heat up.

During the test run, regardless of whether the cookware is placed or not, the overall current of the machine is "zero". When such faults occur, it indicates that the oscillation control part of the induction cooker has stopped working for some reason. The fault points generally exist in the synchronous oscillation circuit, IGBT drive circuit, surge protection circuit, IGBT enable control circuit, and microcontroller circuit.

4、 The induction cooker can be turned on, but intermittent heating occurs.

During the test run, it can be observed that the overall current of the machine increases from a small value to a certain value, then suddenly returns to the "zero" value, and then the overall current increases again, repeating this process. When such faults occur, it can be determined that most of the circuits in the induction cooker are working normally, but there is a certain condition factor that does not meet the requirements during the working process and is forced to stop. Therefore, the following circuits should be inspected with emphasis: synchronous oscillation circuit, IGBT drive, IGBT C-pole high voltage protection circuit, current detection circuit, PWM modulation circuit, and microcontroller circuit.

Repair method for non heating induction cooker:

Firstly, check if the 5uf capacitor capacity is normal. The capacity size should not deviate by 10%. If there is a deviation, replace it.

Secondly, check the resistance values of the 2W 220K, 330K 470K, and 820K resistors near the power circuit. The resistance values of these resistors should not deviate by 5%, and if there is a deviation, no heating will be applied.

Thirdly, check LA339 and if both methods 1 and 2 still cannot solve the problem, you can switch to Lm339

Fourth, check if the secondary coil of the transformer near the power supply circuit is short circuited or open circuited. If it is damaged, replace it

If the above methods still cannot help you solve the problem, please contact the customer service personnel of the induction cooker and ask them to help you find a professional repairman to take a look.