Speaking of air conditioning, I believe many people must be familiar with, in summer, air conditioning can give us to create a comfortable environment, let us better study and work, but also greatly reduce the summer of the irritable breath, in winter, air conditioning can provide us with warmth, let us in the winter can be warm as spring, speaking of air conditioning brand, we will think of Mitsubishi Heavy Industries, Panasonic, Daikin, Gree, With the increasing of air conditioning, air conditioning will also appear a failure, at this time, what should we do? Let me for the air conditioning fault judgment and maintenance of common faults and maintenance methods to do a detailed introduction.
1, the air-conditioning circuit board power circuit failure.
Maintenance method:
Air conditioning circuit board power supply circuit fault characteristics are generally intact and a boot on the fuse. For the former fault, use a multimeter AC stop to measure whether the primary and secondary transformer has 220V and 10-13V voltage, if so, and then use a multimeter DC stop to measure whether 7812 and 7805 have +9-12V and +5V voltage, so as to distinguish the fault location. For the latter, it indicates that there is a short circuit in the circuit, and the ohm stop of the multimeter is used for resistance detection to determine the short circuit position of the circuit. At the same time, it can also use the segmentation method to check, such as by disconnecting the primary winding of the transformer, energizing the test machine. If the fuse is burned, it indicates that the fuse is burned because of the short circuit of the varistor or porcelain capacitor. Otherwise, it is due to the short circuit phenomenon of the transformer or rectifier tube.
2, the air conditioning circuit board temperature sensing circuit failure
Maintenance method:
Thermistor is a negative temperature coefficient thermistor, that is, the higher the temperature, the smaller the resistance, the lower the temperature, the larger the resistance, 25 degrees of resistance value is about 5-20KΩ (depending on the model). Therefore, a multimeter ohmstop can be used to measure its resistance value to determine whether it is good or bad. If the resistance value measured is infinite or small, it indicates that the thermistor has been damaged.
3, the air conditioning circuit board relay circuit failure
Maintenance method:
Firstly, the integrated power drive module is damaged or the relay is damaged. If the buzzer sounds after the remote control is started, but the whole machine does not work, it is generally the integrated power drive module is damaged; If only part of the function is abnormal after startup, it may be the relay is damaged. At this time, we can continue to judge whether the relay coil is burned out or the contact is adhered by listening to whether the relay is closed. There is no closing sound when the relay coil is burned out. Relay can also be used multimeter ohm stop judge good or bad, disconnect the power supply, first measure the coil resistance value, the normal resistance value has several hundred ohm, if infinity or zero, that the relay is damaged; The contact is then measured. If the resistance value is zero, it indicates contact adhesion.
4, the air conditioning circuit board remote control receiving circuit good failure
Maintenance method:
After the device is powered on and started, use a multimeter to measure the voltage of the power supply end of the receiving head and the signal end to ground. The normal value should be the voltage of the power supply pole +5V and the voltage of the signal pole +2.5V. Otherwise it is not normal. Common failures include receiving head damage or capacitor breakdown.
5, air conditioning circuit board reset circuit good failure.
Maintenance method:
Reset voltage is the voltage that delays rising, which can be observed with the DC voltage file of a multimeter. If the observation is not clear, it can also be detected with an oscilloscope. When detecting with an oscilloscope, a baseline can be jitter and then become high, which is the startup process of reset voltage. If no baseline jitter is seen, the reset circuit is faulty.
No matter which electrical appliances and furniture, they will have their own starting mode and use effect, mobile phone it can switch on and off, can download games, download a variety of apps, computer can open various web pages, can develop software, this operation is to be completed by the mode operation of the machine, and no matter what machine electronic equipment, They will have failure, air conditioning is the same, I believe that through the above for air conditioning fault judgment and maintenance of common faults and maintenance methods can let you in some cases of air conditioning have a great help.
