2. The power won't ring when it is plugged into the air conditioner. Maybe the fuse of the air conditioner is blown. If you have strong hands-on ability, you can take it out and put it on yourself. The maintenance price should be between 50-80, pure labor cost and door-to-door maintenance fee.
It is also possible that the transformer is broken and needs to be tested by multimeter. It is known that the primary transformer has 220VAC, and the secondary transformer should have an output of about 13V. If not, the transformer is broken. You can buy the same transformer from the market and replace it. Between 60- 120, maintenance fee plus accessories fee.
4. It will be miserable in the end. Maybe the computer board is broken, the transformer is good and the safety is good. Then maybe the computer board is broken. The maintenance cost of this part can be calculated according to this situation.
First, replace the original, ranging from 200 to 400, mainly depending on the price of accessories provided by manufacturers;
Second, replace the modified board, that is, replace the universal board. The price is between 160-260. The quality of the replaced board is not certain, and some of the original functions of the machine may be lost.
Third, circuit board maintenance, which mainly depends on the ability of repairmen. Ordinary repairmen can't repair computer boards. Relatively speaking, there are some simple faults on the computer board, which may be repaired by the master. If it is repaired well, the cost will be between 160-260, but in most cases, no air conditioner repairman will come to repair the computer board.