The malfunction of the solenoid valve will directly affect the operation of the switching valve and regulating valve. Common faults include the solenoid valve not operating, and should be investigated from the following aspects:

(1) If the wiring head of the solenoid valve is loose or the wire head falls off, the solenoid valve cannot be powered, and the wire head can be tightened.

(2) The solenoid valve coil is burnt out. The wiring of the solenoid valve can be removed and measured with a multimeter. If there is an open circuit, the solenoid valve coil is burnt out.

The reason is that the coil is damp, causing poor insulation and magnetic leakage, resulting in excessive current inside the coil and burning out. Therefore, it is necessary to prevent rainwater from entering the solenoid valve. In addition, if the spring is too hard, the reaction force is too large, the number of turns in the coil is too small, and the suction force is not enough, it can also cause the coil to burn out. When dealing with emergencies, the manual button on the coil can be moved from the "0" position during normal operation to the "1" position to open the valve.

(3) The solenoid valve is stuck. The clearance between the slide valve sleeve and the valve core of the solenoid valve is very small (less than 0.008mm), usually assembled as a single piece. When mechanical impurities are introduced or there is too little lubricating oil, it is easy to get stuck. The processing method can be to insert a steel wire through the small hole in the head and make it bounce back. The fundamental solution is to remove the solenoid valve, take out the valve core and core sleeve, clean them with CCI4, and make the valve core move flexibly inside the valve sleeve. When disassembling, attention should be paid to the assembly sequence and external wiring position of each component, in order to reassemble and wire correctly. It is also necessary to check whether the oil mist spray hole is blocked and whether the lubricating oil is sufficient.

(4) Leakage. Leakage can cause insufficient air pressure, making it difficult to open and close the forced valve. The reason is that the sealing gasket is damaged or the slide valve is worn, causing several cavities to blow air.

When dealing with electromagnetic valve faults in the switching system, an appropriate timing should be chosen to handle them when the solenoid valve is in a power-off state. If the problem cannot be resolved within a switching gap, the switching system can be paused and handled calmly.