... consumption 4.Low pollution,low noise ORL series CNG power unit are very suitable for home use with ... fuel efficiency, stable output, low noise. Especially,the power units from 12-20kw are mostly welcomed by customers ... because of proper capacity,low noise(use gasoline or gas as fuel),small size and low weight. They' ... machinewhile machine working abnormal. 12KW CNG(Compressed Natural Gas) power unit