NANO

844 HVAC The areas for inspection (steps) are given according to various circuit malfunctions. Use the chart below to verify the symptoms of the trouble in order to diagnose the appropriate area. No. Troubleshooting Item Description 1 Air from vents not cold enough Magnetic clutch operates but A/C system malfunction 2 No cool air Magnetic clutch does not operate 3 Noise while operating A/C system Noise from magnetic clutch, A/C compressor, hose or refrigerant line 1 Air from vents not cold enough TROUBLESHOOTINGHINTS • Drive belt malfunction Step 1 • Malfunction in blower unit or condenser Step 4, 5 • Malfunction in receiver / drier, expansion valve ( valve close too much) or expansion valve heat-sensing tube installed incorrectly Step 8, 9 • Malfunction in refrigerant lines Step 10- 13 • A/C compressor system malfunction, insufficient compressor oil Step 16 • Too much compressor oil, expansion valve heat-sensing tube installed incorrectly, or malfunction in expansion valve or heater unit’s air mix link system Step 18- 19 1 2 3 4 INSPECT DRIVE BELT See whether the belt is existing or fitted with correct tension. INSPECT REFRIGERANT SYSTEM PERFORMANCE Perform refrigerant systemperformance test (ReferAC system performance test) Is operating normal? VERIFYWHETHERMALFUNCTION IS IN BLOWER UNIT INTAKE AND CONDENSERORANOTHER Are refrigerant’s high-pressure and low pressure values both high? INSPECT BLOWER UNIT INTAKE Is blower unit intake clogged Yes Go to next step No Adjust or replace drive belt. Yes Operation is normal. ( Recheck malfunction symptoms.) No Go to next step Yes Go to next step. No Go to step6. Yes Remove obstruction. ( Ifairdoesnot reach evaporatorwithin coolingunit, heat exchangedoesnot occur and refrigerant pressurebecomeshigh, therefore, removal obstruction is necessary.) No Go to next step STEP INSPECTION ACTION TROUBLESHOOTING CHART (B)