The display reading also not gradually UP and down

Hi Dinesh,

I don't really understand what your question is. But it sounds like you are having trouble with the controls/display of the controller??? 

If the controller buttons and lcd display have been  'abused' and are now worn.. the only thing you can do really is to replace it with a new controller.  Call Atlas Copco because you can't just get any controller (the same controller is used on many machines) - it needs to have been programmed to work for your compressor (GA55).

Best,

Cas