6Troubleshooting ChartSymptom Possible Cause(s) Corrective Action1. No electrical power2. Blown fuse3. Breaker open4. Thermal overload open5. Pressure switch bad6. Check valve defective1. Poor contacts, line voltage incorrect2. Shorted or open motor winding3. Defective check valve or unloader1. Incorrect size fuse, circuit overloaded2. Defective check valve or unloader1. Low voltage2. Clogged air filter3. Lack of proper ventilation/roomtemperature too high4. Check valve malfunction1. Leaking, broken, or loose valves orrestricted air passage2. Defective pressure switch unloader3. Defective bearing on eccentric ormotor shaft4. Cylinder or piston ring is worn orscored5. Loose bolts, tank not level1. Plugged in? Check fuse/breaker or motor overload2. Replace blown fuse3. Reset, determine cause of problem4. Motor will restart when cool5. Replace6. Remove and replace check valveDo not disassemble check valvewith air in tank; bleed tank1. Check connections, check with voltmeter2. Replace motor3. Replace or repairDo not disassemble check valvewith air in tank; bleed tank1. Check for proper fuse, use time-delay fuse.Disconnect other electrical appliances from circuit oroperate compressor on its own branch circuit2. Replace or repairDo not disassemble check valvewith air in tank; bleed tank1. Check with voltmeter2. Clean filter (see Maintenance section)3. Move compressor to well ventilated area4. ReplaceDo not disassemble check valvewith air in tank; bleed tank1. Replace2. Replace or repair as necessary3. Replace4. Replace or repair as necessary5. Tighten bolts, shim tank to level position! DANGER! DANGER! DANGER! DANGERCompressor will not runMotor hums but cannotrun or runs slowlyFuses blow/circuitbreaker trips repeatedlyNever use an extensioncord with this productThermal overloadprotector cuts outrepeatedlyKnocks, rattles,excessive vibration! CAUTIONOilless Compressorswww.chpower.com