The general rule of screw air compressor inlet valve is: after power failure, the inlet valve must be loaded unloaded electrically.

Sometimes, the current of our equipment will be slightly larger when unloading, while the current when unloading 22KW is 31a. I initially suspected that the intake valve was tight, because when the gas was used, the pressure of the machine would rise slowly after unloading, sometimes the high pressure alarm would close! after the shutdown, there is still some residual pressure (about 6 kg) that can be released inside the machine, which causes the main engine to be overloaded when restarting.

When the inlet valve of screw air compressor is normally open, the solenoid valve opens when the screw air compressor is loaded, closes when the compressor is loaded. When the solenoid valve is opened, there will be gas to close the intake valve, but it cannot be completely closed. The intake space must be reserved to maintain the low pressure required for compressor lubrication. This pressure is usually 1.5 bar; then close the solenoid valve the compressor will enter normal operation until the set working pressure is reached, depending on the user.

The intake valve has two pipes, one is empty the other is empty. Another method is to release the residual air in the valve to ensure the normal load of the compressor. When unloading, the current is too large, indicating that the tank pressure is high the inlet valve opening is large. Please adjust the exhaust screw to ensure that the tank pressure is too high.

After the screw air compressor stops, the tank pressure can be completely drained in about 60 seconds, i.e. the pressure is 0, your tank pressure is still 6 bar, which indicates that there is a problem with the intake valve exhaust pipe:

1.The pipe diameter may be too small;

2. The orifice of combination valve is too small whether it is blocked by debris。

After unloading, the pressure will rise back forth slightly, but this is only to keep balance, the time is very short. It will rise to a high pressure shutdown condition. The air compressor solenoid should be a high pressure shutdown problem. Please check that it is complete working properly. No matter which type of intake valve, when unloading between bars, the tank pressure shall be kept at 1.0-2.0. Too high for screw air compressor is a huge waste of energy.