Samsung MH026FNCA Service Manual

Also see for MH026FECA: Service manual

6.Troubleshooting4. Checking Display PCB LED if Error code is displayed.See error code table if displayed.5. Checking DC voltage on each pointItem Measuring point Normal valueDC LINK Q803 E(-)~D101 Cathode (+) about 1.4 times as much as Power AC Voltageex) AC220V → 305~310Vdcinverter 15V C803 voltage 14.5V~15.5VMain control 12V CN59 pin 1~pin 3 12V~15VMain control 5V CN59 pin 1~pin 2 4.75V~5.25V6. Checking PFCWhen Input current is over 2.8A PFC circuit will work to control the harmonics of AC current.Checking is measuring DC-LINK voltage.PFC ON (Compressor is working) : DC LINK voltage is over 300Vdc (AC line >220V )After starting compressor DC Link voltage is going down because of compressor load.But in case of 2.8A above , DC link voltage will go up over 300V. This voltage is in proportion to AC input voltage.Current can be monitored with "VIEW MODE".Press K4 key on the outdoor display PCB for several times to change the display to sensor temperature value.Left 1 digit of the LED is data index and Right 3 digits are the valueIndex Value RemarkC Estimated Primary current value from The unit is 0.1ACompressor currentSamsung Electronics9-15