Solution: After replacing the relay with the same model, the fault was eliminated.
Fault Symptoms: After turning on the air conditioner, the outdoor unit fan can start and run normally, but the compressor does not work.
Article Source: Beijing Xinke Air Conditioning Repair Phone http://blog.tianya.cn/blogger/blog_main.asp?BlogID=3637766.
Analysis and Maintenance: Observing the fault symptoms, it is judged that a certain component in the compressor control circuit is damaged or the compressor itself is faulty. The working principle of the compressor control circuit of this air conditioner is as follows: when the microcomputer chip u PD75208 sends an instruction to turn on the machine, pin 36 outputs a high level, and at the same time, pin 10 of IC2 outputs a low level, so the contact of the coil of the compressor control relay Y6 closes, and the compressor is powered on and starts. If due to constant temperature shutdown, protective shutdown or other reasons, pin 36 of the chip outputs a low level, pin 10 of IC2 outputs a high level, then the +12V closed loop of the compressor control relay Y6 will be lost, and the K6 contact opens, and the compressor has no 220V loop and stops running.
After analyzing the above principles, it was found that pin 36 of the chip has a high-level output, pin 10 of IC2 has a low-level output, but there is no 220V voltage between the blue and red lines at the outdoor unit. Following the red line towards the indoor unit, it was found that the compressor control relay did not close, and its coil had opened.
Xinke KFR-25W type split air conditioner, the compressor does not work.