1. Faulty Discharge Valve
The discharge valve should close during loading; if it fails to close, it will directly lead to a pressure drop. Check whether the discharge valve is stuck or damaged, and carry out necessary repairs or replacements.

2. Improper Pressure Switch Settings
If the pressure switch is set too low, it will result in insufficient compressor pressure. Readjust the pressure switch setting to ensure it meets system requirements.

3. Faulty Pressure Gauge
A damaged or inaccurate pressure gauge may display incorrect pressure readings. Replace the pressure gauge to obtain accurate pressure measurements.

4. Air Leak in Control Piping
Leaks in the control piping can affect the opening of the intake valve, thus impacting the output pressure of the unit. Inspect and repair any leaks to ensure the integrity of the control piping.

5. Supply and Demand Imbalance
When air demand exceeds supply, pressure will also drop. Check that all valves in the system are fully open, investigate any leaks, and try to reduce air usage.

6. Clogged Air Filter
A clogged air filter will restrict airflow into the compressor, reducing its efficiency. Regularly check and replace the filter element to ensure unobstructed airflow.

7. Issues with the Pressure Regulator
A damaged or malfunctioning pressure regulator can affect the pressure adjustment of the compressor. Replace or adjust the pressure regulator promptly to ensure it functions properly.

8. Blocked Oil-Gas Separator
Clogging in the oil-gas separator will increase the resistance to air flow, affecting compressor performance. Replace the filter element in a timely manner, according to the equipment’s display information, to maintain good separation efficiency.

9. Intake Valve Issues
An intake valve that cannot fully open will directly reduce the intake volume of the compressor, leading to insufficient pressure. Check the intake valve for faults and carry out repairs or adjustments as needed.

By thoroughly analyzing these common issues and proposing solutions, we can effectively resolve low-pressure problems in screw compressors. Regular inspections and maintenance are key to ensuring stable operation of the equipment.