The main manifestations of air compressor not pumping up and insufficient air pressure are as follows: the air compressor does not discharge air under pressure and when the main engine is running and the air compressor is inflating the air tank, the barometer indicates the starting pressure value of the air pressure.

A: General reasons and solutions for the air compressor not pumping up when loaded

1. The intake valve is not open   

When the air compressor is turned on, the internal pressure is slowly built up. When the pressure reaches 5Bar (this is the case for most air compressors, except for special cases), the solenoid valve controls the cylinder to open the intake valve, and the air compressor sucks air into the loading state. There may be three reasons why the air compressor does not intake air: solenoid valve (circuit, valve body, pipeline), cylinder (valve or diaphragm, seal, pipeline), intake valve (valve or diaphragm, seal, pipe) Circuit is malfunctioning. 

2. Fake loading of air compressor   

The fake loading of the air compressor is mainly caused by the failure of the output point of the PLC. The PLC is in the running loading state. Due to the failure of the output point, no signal is given to the solenoid valve, which causes the air intake machine to fail to operate. A professional air compressor maintenance engineer is required to repair the PLC. Non-professionals are not recommended to disassemble it at will. 

3. The minimum pressure check valve failure    

The minimum pressure check valve is the easiest to judge whether there is a malfunction. When the internal pressure is high but there is no pressure output, it can be judged that the minimum pressure check valve is malfunctioning. The best way for the minimum pressure check valve to fail is to replace it.  

4. The main engine of the air compressor is malfunctioning   

The failure of the air compressor host is the most difficult to solve. The host failures include:   

Female and yang rotor wear: When there is a lot of wear between the female and male rotors and between the inner cavity of the stator, the internal leakage of the air compressor is very large, and the air compressor will not be loaded when it is loaded;   

Air compressor lubricating oil: The price of special oil for screw air compressor is slightly more expensive. Some illegal suppliers provide users with non-air compressor special oil, which makes the air compressor lubricating oil emulsify and cannot form an effective air seal. As a result, the efficiency of the air compressor is very low, and even no gas is produced. At this time, the air compressor operator can hear that the noise of most air compressors when they are actually completely empty and when they are actually loaded is very different, mainly because the noise on the suction side is very obvious. When the internal leakage is large, there will be noise changes at the suction end and no pressure will be generated. This situation can confirm that the air compressor is lazy and not pumping up. The failure of air compressor to load is a common air compressor failure. General professional air compressor maintenance personnel can help you solve this problem quickly. 

B: Reasons for the failure of insufficient air pressure  

The barometer is malfunctioning.  

The transmission belt between the air compressor and the engine is too loose and slippery, or the management between the air compressor and the air tank is broken or the joint is leaking.  

The oil-water separator, pipeline or air filter is clogged due to excessive deposits and requires regular maintenance.  

The air compressor exhaust valve sheet is not tightly sealed, the spring is too soft or broken, the air compressor cylinder head bolts are loose, sand holes and cylinder head gaskets are washed out and air leaks.