SiBE05-722EE General Problem Symptoms and Check ItemsService Diagnosis 591. General Problem Symptoms and Check ItemsSymptom Check Item Measures ReferencePageThe unit does not operate. Check the power supply. Check if the rated voltage is supplied. —Check the type of the indoor unit. Check if the indoor unit type is compatible withthe outdoor unit. —Check the outdoor temperature. Heating operation is not available when theoutdoor temperature is 18°CWB or higher, andcooling operation is not available when theoutdoor temperature is below –10°CDB.—Diagnose with remote controllerindication. — 64Check the remote controlleraddresses. Check if address settings for the remotecontroller and indoor unit are correct. 119Operation sometimesstops. Check the power supply. A power failure of 2 to 10 cycles stops airconditioner operation. (Operation lamp OFF) —Check the outdoor temperature. Heating operation is not available when theoutdoor temperature is 18°CWB or higher, andcooling operation is not available when theoutdoor temperature is below –10°CDB.—Diagnose with remote controllerindication. — 64The unit operates but doesnot cool, or does not heat. Check for wiring and piping errors inthe connection between the indoorunit and outdoor unit. — —Check for thermistor detection errors. Check if the thermistor is mounted securely. —Check for faulty operation of theelectronic expansion valve. Set the unit to cooling operation, and check theliquid pipe temperature to see if the electronicexpansion valve works. —Diagnose with remote controllerindication. — 64Diagnose by service port pressureand operating current. Check for refrigerant shortage. 70Large operating noise andvibrations Check the output voltage of thepower module. — 112Check the power module. — —Check the installation condition. Check if the required spaces for installation(specified in the installation manual) areprovided. —
