Problem Symptoms and Measures SiENBE07-618_C56 Service Diagnosis2. Problem Symptoms and MeasuresSymptom Check Item Details of Measure ReferencePageThe units does not operate. Check the power supply. Check to make sure that the rated voltage issupplied. —Check the type of the indoor units. Check to make sure that the indoor unit type iscompatible with the outdoor unit. —Check the outdoor temperature. Heating operation cannot be used when theoutdoor temperature is 18°C or higher, andcooling operation cannot be used when theoutdoor temperature is below –10°C.—Diagnose with remote controlindication. — 60Check the remote control addresses. Check to make sure that address settings forthe remote control and indoor unit are correct. —Operation 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 cannot be used when theoutdoor temperature is 18°C or higher, andcooling operation cannot be used when theoutdoor temperature is below –10°C.—Diagnose with remote controlindication. — 60The unit operates but doesnot cool, or does not heat. Check for wiring and piping errors inthe connection between the indoorand outdoor units.Conduct the wiring/piping error check describedon the product diagnosis label. —Check for thermistor detection errors. Check to make sure that the thermistor ismounted securely.—Check for faulty operation of theelectronic expansion valve.Set the units to cooling operation, and checkthe temperature of the liquid pipe to see if theelectronic expansion valve works.—Diagnose with remote controlindication. — 60Diagnose by service port pressureand operating current. Check for refrigerant shortage. 90Large operating noise andvibrations Check the output voltage of thepower module. — 99Check the power module. — —Check the installation condition. Check to make sure that the required spacesfor installation (specified in the installationmanual, etc.) are provided.—