Grasso

[seanf]

https://flic.kr/p/2mR1rgv

Grasso GR-G30S-28.
Fixed Vi.


When the suction to discharge pressure difference is high the noise gets worse. Starting about 2.6 bar suction, 9.8 bar discharge and 30% slide, itll go quieter on more slide.
But bigger diff louder it becomes and it stays even with more slide.
Smaller diff, say 9.0 bar and 3.5 bar the noise goes or very faint.
The noise mainly seems to be around the underside of the comp, under the loading solenoids area.
Its on a two comp pack, when running the second comp on its own you dont get any unusual noise out of it.