Why Does the Four Way Reversing Valve Have Poor Commutation?

There are a number of possible causes for a poor reversing of a four way reversing valve, the following are some common possible causes:

1. Abnormal solenoid valve: Four way reversing valves are usually controlled by solenoid valves, if one of the solenoid valves fails or is damaged, it may cause poor commutation. This can be caused by a faulty solenoid valve coil, a stuck spool, or aging seals.

2. Oil pollution: If there are contaminants in the hydraulic oil or lubricating oil in the system, such as impurities, particles or deposits, it may cause poor movement or blockage of the internal parts of the four way reversing valve, resulting in poor commutation.

3. The temperature of the hydraulic oil is too high: If the oil temperature of the hydraulic system is too high, the viscosity of the hydraulic oil may be reduced, which will affect the movement and sealing performance of the four way reversing valve, resulting in poor commutation.

4. Abnormal pressure of the hydraulic system: If the working pressure of the hydraulic system exceeds the rated pressure range of the four way reversing valve, or there is pressure pulsation or excessive pressure, it may cause the normal movement of the four way reversing valve to be blocked or unstable, resulting in Poor commutation.

5. Spool wear or damage: Long-term use or improper use may cause the spool of the four way reversing valve to wear, damage or deform, thereby affecting its normal reversing function.

6. Operation error or human intervention: Incorrect operation or human intervention may cause poor reversing of the four way reversing valve, such as wrong operation sequence, too fast or too slow reversing action, or external intervention causing damage to the valve body wait.

There are many factors that cause the four way reversing valve not to change direction, and it often shows that it is not cooling or heating during maintenance. The troubleshooting methods are as follows:

(1) First check whether the refrigerant in the system is sufficient (it is not comprehensive to judge whether the pressure of the system is sufficient).

(2) Check the system for leakage of refrigerant resulting in loss of refrigerant.

(3) Check whether the four way reversing valve body and capillary are damaged or deformed.

(4) Judging whether the coil on and off is normal, and whether the voltage is within the allowable range.

(5) Determine whether the pilot valve is in action. When the coil is turned on and off, there is a spool impact sound of "tower, tower, tower", indicating that the pilot valve operates normally. At this time, it is best to only energize the four way reversing valve in order to listen to the sound.

(6) The pilot valve acts normally, but the main valve body does not act, indicating that the minimum operating pressure difference required for the four way reversing valve reversing has not been established. It is possible to charge enough refrigerant into the system to make it commutate normally.

The possible causes and troubleshooting methods listed above are just some common situations, and the specific problems need to be checked and diagnosed according to the actual situation. If you encounter the problem of poor commutation of the four way reversing valve, it is recommended to contact a professional hydraulic system technician or maintenance personnel for detailed troubleshooting and repair.