Samsung MH026FNCA Service Manual

Also see for MH026FECA: Service manual

9-1Samsung Electronics1. The input voltage should be rating voltage ±10% range.The air conditioner may not operate properly if the voltage is out of this range.2. Is the link cable linking the indoor unit and the outdoor unit linked properly?The indoor unit and the outdoor unit shall be linked by 4 wires.2 wires are for power and other 2 wires are for communication, total 4 wires on each indoor unit. Check the terminals if theindoor unit and outdoor unit are properly linked by the same number of cables and if connecting position on the terminal iscorrect. Otherwise the air conditioner may not operate properly.3. When a problem occurs due to the contents illustrated in the table below it is a symptom not related to the malfunction of theair conditioner.Operation of air conditionerNo123456789-1 Items to be checked first9. TroubleshootingIn a COOL operation mode, the compressor does notoperate at a room temperature higher than the settingtemperature that the INDOOR FAN should operate.In a HEAT operation mode, the compressor does notoperate at a room temperature lower than the settingtemperature that indoor fan should operate.Fan speed setting is not allowed in AUTO( ) orDRY( ) mode.Compressor stops operation intermittently inDRY( ) mode.Compressor of the outdoor unit is operating althoughit is turned off in a HEAT mode.Timer LED( ) only of the indoor unit lights up andthe air conditioner does not operate.The compressor and indoor fan stop intermittently inHEAT mode.Indoor fan and outdoor fan stop operationintermittently in a HEAT mode.The compressor stops intermittently in aCOOL mode or DRY mode, and fan speed of theindoor unit decreases.ExplanationIn happens after a delay of 3 minutes when the compressoris reoperated. The same phenomenon occurs when a poweris on.As a phenomenon that the compressor is reoperated after adelay of 3 minutes, the indoor fan is adjusted automatically withreference to a temperature of the air blewThe speed of the indoor fan is set to LL in DRY mode.Fan speed is 5 steps and is selected automatically in AUTOmode.Compressor operation is controlled automatically in DRY modedepending on the room temperature and humidity.When the unit is turned off while de-ice is activated, thecompressor continues operation for up to 12 minutes (maxi-mum) until the deice is completed.Timer is being activated and the unit is in ready mode.The unit operates normally if the timer operation is cancelled.The compressor and indoor fan stop intermittently if roomtemperature exceeds a setting temperature in order to protectthe compressor from overheated air in a HEAT mode.The compressor operates in a reverse cycle to removeexterior ice in a HEAT mode, and indoor fan and outdoor fando not operate intermittently for within 20% of the total heateroperation.The compressor stops intermittently or the fan speed of theindoor unit decreases to prevent inside/outside air frozendepending on the inside/outside air temperature.