**Gentle Reminder:** The capacitor-start method is based on the forced-start method, and involves adding a 50uF capacitor in series on the S terminal wire. After this capacitor is connected in series with the start terminal, the starting torque of the compressor can increase by about 50%. However, after starting the compressor using this method, the running time should not be too long because increasing the capacitance at the start terminal causes overheating of the compressor, which can easily lead to the destruction of the start winding coil.
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**Fault Phenomenon:** Mitsubishi air conditioner, the compressor is powered for about 10 seconds before overheating or overcurrent protection trips.
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**Analysis and Testing:** Measured the power supply voltage as normal. Removed the outdoor unit casing and tested the compressor start capacitor, which showed good charging and discharging performance. Then measured the three terminals of the compressor: the sum of the resistance of the main winding (M) and the auxiliary winding (S) was approximately equal to the resistance of the common terminal (C), indicating that the compressor windings were normal.
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**Repair Method:** Neither the wooden hammer tapping method nor the forced-start method worked. Finally, the increased-capacitance start method was used, allowing the compressor to start and run smoothly.
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**Data Source:** Beijing Mitsubishi Air Conditioning Repair
[http://blog.tianya.cn/blogger/blog_main.asp?BlogID=3760866](http://blog.tianya.cn/blogger/blog_main.asp?BlogID=3760866)
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**Case Analysis by Beijing Mitsubishi Air Conditioning Repair Center:** August 28, 2011