... , specially the 68 decibel (dB)working noise is much lower than the standard approval of ISO3746,The product ... water to reduce the temperature. When the temperature is lower than 4°C, please open the vent first ... only be lower than 6-7mpa, or the fuse is always burn-out, the machine is felt very ... Causes:Level 4 compressing piston or retaining valve is not working properly, mainly because of the problem ...