The solution here is to check and clean the unidirectional valve, replacing it when necessary. Improper installation or blockage of the oil return pipeline will impede the normal return of the lubricating oil.
[pdf] Choosing the optimal oil for your screw compressor should consider various factors: Manufacturer specifications: Always consult the manufacturer's recommendations regarding viscosity and oil type. Operating conditions: Evaluate ambient temperature, duty cycles, and typical compressor loads.
[pdf] First, check that there isn't a very high air demand, or air leak somewhere. If the capacity of the air compressor is really too low, check the following: Check differential pressure over oil separator. Replace separator when necessary. Check and replace compressed air filters (if installed).
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