Air compressor not building up pressure past 2 bar

[nadim sadiq]

I have a large 200ltr air compressor was working fine then all of a sudden it won't build up pressure more then 2bar no matter how long it runs for any one any advice please thank you 

[maybelateron]

If it keeps running all the time it is unlikely to be the pressure sensing switch for the motor, because if that was faulty it would shut the motor off once 2bar is achieved. I think a leak somewhere after the compressor pump is an option, or that the pump is faulty, eg head gasket or flap valves.