Fault  Phenomenon Cause Solution
Rough valve can not be opened Compressed improper air pressure Pressure should be 0.4-0.6MPa.
Electromagnetic directional valve of rough valve can’t work. Refer to fault phenomenon 2
Overtravel-limit switch of high vacuum valve is not compacted. Adjust switch and upper cover plate to a suitable place.
Electromagnetic directional valve can’t work. No actuation with electricity Change coil or whole valve
Working temperature is low. Temperature should be higher than 5℃.
Valve Pump body is blocked. Clean valve body and add pump oil
Air source pressure is not enough. Pressure should be 0.4-0.6MPa
Fore valve can not be opened. Deficient air pressure Refer to fault phenomenon 2
Electromagnetic directional valve can’t work. Refer to fault phenomenon 2
High vacuum valve can not be opened. Overtravel-limit switch of rough valve is not compacted. Adjust switch and upper cover plate to a suitable place
Gas source pressure is not enough. Should be 0.4-0.6MPa
Electromagnetic directional valve Refer to fault phenomenon 2
Vacuum degree is not enough (Can not reach vacuum meter setting value) Compound vacuum meter(working) setting value is not less than 5Pa
Front valve is not opened. Open front valve under a certain condition
Roots pump is not opened. Vacuum electric contact pressure gage can’t work well. Pumping air, make big round meter indicator to the left end
Time-delay is not completed Wait
Air switch is not connected Connect switch if no issue
Diffusion pump can’t work. Heating time is not enough KT-400 requires 1 hour; KT-600 requires 80 minutes
Oil pollution Change pump oil (Dalian NO.3)
Vacuum rough pumping is not high. Vacuum degree should be higher than 5Pa.
Cooling water is not unimpeded. Clean pump cooling water path
Improper oil volume Add oil or release oil
Air inflation can not work. Rough valve and high vacuum valve overtravel-limit switch is not compacted Adjust switch and upper cover plate to a suitable place
Electromagnetic charging valve is not working Change coil or valve
Fan is not opened. Electro connecting pressure can’t work well. Wait for inflation pressure until 0.02MPa
Rough valve and high vacuum valve overtravel-limit switch is not compacted. Adjust switch and upper cover plate to a suitable place
Air switch is not connected. Connect switch if no issue
Motor is damaged. Fix or change motor
Heating current is not balanced confoundedly. Heating voltage close to rated value, current is 0, heater band is broken. Use molybdenum filament to connect or change heater band
Heater band is connected with wall. Use ceramic parts to insulate
Mutual inductor is broken with voltage but no current. Change  mutual inductor
Ammeter and voltmeter are broken. Change  meters