First, the solenoid valve does not work after power Check the power supply connection is not good → re-wiring and connector connection Check the power supply voltage is within the scope of work → → tune the normal range of the coil is not desoldering → re-welding coil short circuit → replace coil work pressure The difference is not appropriate → adjust the pressure difference → or replace the appropriate solenoid valve fluid temperature is too high → replace the solenoid valve has the appropriate impurity impurities so that the main solenoid valve solenoid valve and move the core → cleaning, seal damage should be replaced Sealed and installed filter Liquid viscosity is too high, the frequency is too high and life has been → Replace the product Second, the solenoid valve can not close the main spool or iron core seal has been damaged → Change the seal fluid temperature, viscosity is too high → Replace the opposite solenoid valve impurities into the solenoid valve spool or move the core → cleaning spring has reached or deformed life → replace the orifice balance hole blocked → promptly clean the working frequency is too high or life has been to → re-election product or update Third, the other leaks → check the seal is damaged, the spring is assembled Defective external leaks → loose connections or seals have been damaged → tight screws or replace the seal noise when the power is → head fasteners loose, tighten. Voltage fluctuation is not within the allowable range, adjust the voltage. Core suction surface impurities or uneven, timely cleaning.