1、 Electromagnetic coil malfunction

1. Coil burnout
   • reason：
     • The power supply voltage is too high or too low, exceeding the rated range of the coil.
     • The coil operates under long-term overload (such as frequent start stop or prolonged power on).
     • The insulation of the coil is damaged, resulting in short circuit or leakage.
   • performanceThe coil is heating up, smoking, and has a burnt smell, and the solenoid valve cannot operate.
   • solve：
     • Check if the power supply voltage is stable and adjust it to the rated range.
     • Replace the coil with one that meets the specifications to avoid overloading during use.
     • Regularly check the insulation performance of the coil and replace aged coils in a timely manner.
2. Coil open circuit
   • reason：
     • Internal wire breakage of the coil (such as vibration, mechanical damage).
     • Loose or corroded wiring terminals result in poor contact.
   • performanceThe solenoid valve does not operate, and there is no current passing through the coil (measured with a multimeter to show infinite resistance).
   • solve：
     • Re weld or replace the coil.
     • Tighten the wiring terminals, remove the oxide layer, and ensure good contact.

2、 Pilot valve malfunction

1. Pilot valve blockage
   • reason：
     • Impurities in the medium, such as iron filings, oil stains, and particulate matter, enter the pilot valve hole, causing blockage.
     • The medium is highly corrosive, causing scaling or rusting on the inner wall of the pilot valve hole.
   • performanceThe solenoid valve cannot be opened or closed, or its action is slow.
   • solve：
     • Clean the pilot valve hole to remove impurities and scale.
     • Install a filter in front of the valve and regularly replace the filter element.
     • Choose solenoid valves made of corrosion-resistant materials such as stainless steel and plastic.
2. Pilot valve spring failure
   • reason：
     • Long term compression or fatigue of springs can lead to weakened or broken elasticity.
     • The spring material is not corrosion-resistant and loses its elasticity after rusting.
   • performanceThe solenoid valve cannot remain closed or the opening pressure is insufficient.
   • solve：
     • Replace the spring with one that meets the specifications.
     • Choose corrosion-resistant spring material (such as stainless steel).

3、 Main valve malfunction

1. The main valve is not tightly sealed
   • reason：
     • The sealing surface of the main valve is worn or scratched (such as hard particles in the medium).
     • The sealing gasket is aging, deformed, or damaged.
   • performanceAfter the solenoid valve is closed, there is still leakage and the medium cannot be cut off.
   • solve：
     • Grind or replace the sealing surface of the main valve.
     • Replace the sealing gasket to ensure compatibility between the material and the medium.
2. Main valve stuck
   • reason：
     • Low medium temperature leads to increased viscosity or crystallization of the medium (such as water freezing).
     • There are impurities or foreign objects stuck inside the main valve.
   • performanceThe solenoid valve operates slowly or fails to operate.
   • solve：
     • Heating medium or use low-temperature solenoid valve.
     • Clean the inside of the main valve to remove impurities and foreign objects.

4、 Power and control failures

1. Power issue
   • reason：
     • The power supply is not connected or has poor contact.
     • Unstable power supply voltage (such as excessive fluctuations or harmonic interference).
   • performanceThe solenoid valve does not operate or operates unstably.
   • solve：
     • Check the power circuit to ensure good contact.
     • Use a regulated power supply or add a filter to reduce voltage fluctuations and harmonic interference.
2. Control signal malfunction
   • reason：
     • Control signal not input or input error (such as abnormal PLC output signal).
     • Control circuit open circuit or short circuit.
   • performanceThe solenoid valve cannot operate according to the command.
   • solve：
     • Check the control signal source (such as PLC, switch) to ensure that the signal is normal.
     • Use a multimeter to check the control circuit and repair any open or short circuits.

5、 Malfunctions caused by environmental factors

1. Corrosion of media
   • reasonThe medium has strong corrosiveness (such as acid, alkali, salt solution), which corrodes the internal components of the solenoid valve.
   • performanceElectromagnetic valve leakage, slow action or failure.
   • solve：
     • Choose solenoid valves made of corrosion-resistant materials such as stainless steel, plastic, and fluorine lining.
     • Regularly check the corrosion of the solenoid valve and replace it in a timely manner.
2. The ambient temperature is too high or too low
   • reason：
     • Excessive ambient temperature can lead to a decrease in coil insulation performance or aging of seals.
     • Low ambient temperature leads to increased viscosity or freezing of the medium.
   • performanceThe performance of the solenoid valve has decreased or failed.
   • solve：
     • Choose high or low temperature resistant solenoid valves.
     • Improve the installation environment, such as adding heat dissipation devices or insulation measures.

6、 Improper installation and maintenance

1. Installation direction incorrect
   • reasonThe installation direction of the solenoid valve does not match the flow direction of the medium.
   • performanceThe solenoid valve is not functioning properly or leaking.
   • solveReinstall the solenoid valve to ensure that the arrow direction is consistent with the flow direction of the medium.
2. Maintain deficiencies
   • reasonLong term failure to clean, inspect, or replace vulnerable parts.
   • performanceThe performance of the solenoid valve deteriorates or suddenly malfunctions.
   • solve：
     • Regularly clean the inside of the solenoid valve to remove impurities and scale.
     • Check and replace aging or damaged components (such as gaskets, springs).