Fault 1: No action when electrified Reason analysis: Poor connection of power supply wiring; power supply voltage fluctuation is not within the allowable range; coil short circuit or burnt out. Treatment method: connect the power cord; adjust the voltage within the normal range; replace the coil. Fault 2: When the valve is opened, the fluid cannot pass the reason analysis: the fluid pressure or working pressure difference does not meet; the fluid viscosity or temperature does not meet; the valve core and the moving iron core are mixed with dirt and impurities; the filter before the valve or the pilot valve hole is blocked ; The working frequency is too high or the life is expired during use. Treatment method: adjust the pressure or working pressure difference or replace the suitable product; replace the suitable product; clean the interior, the filter valve must be installed before the valve; clean the filter or pilot valve hole in time; change the product model or replace the new product. Fault 3: The fluid cannot be cut off when the valve is closed. Reason analysis: fluid viscosity does not meet; fluid temperature does not meet; spring deformation or expiration of life; valve seat is defective or adhered to dirt; gasket protrudes, defect or deformation; balance hole or joint Orifice clogged; use too high frequency or expired life. Treatment method: replace the appropriate product; replace the appropriate product; add a gasket or replace the spring; clean, grind or update; Fault 4: External leakage Cause analysis: The pipe connection is loose; the outer seal of the pipe connection is damaged. Treatment method: Tighten the bolt or takeover thread; replace the seal. Fault 5: Serious cause analysis of internal leakage: the fluid temperature does not meet the requirements; the pilot valve seat and the main valve seat have impurities or defects; the pilot valve and the main valve gasket are protruded or deformed; the spring assembly is poor, deformed or its life is expired; The frequency is too high. Treatment method: adjust the fluid temperature or replace; if there is, clean or grind to repair or replace; replace the gasket; replace the spring; change the product model or replace it with a new product. Fault 6: Excessive noise when energized Cause analysis: loose fasteners; voltage fluctuations, not within the allowable range; unsuitable fluid pressure or working pressure difference; fluid viscosity does not meet; there are impurities on the armature suction surface. Treatment method: tighten; adjust to the normal range; adjust the pressure or working pressure difference or replace the product; replace the suitable product; clean in time.