"Blower Fan" lubricant 3 to 6 months to be replaced once or one at a time with a pore size less than 50 microns copper mesh. The first time after starting work up to 200 hours, it should be oil changes. Muffler also advised about half a year overhaul, replacement of some or all of the sound-absorbing material. Speed increases often have to replace the larger motors. Air filter should be regularly maintenance, import and export of valves, the bypass tube should maintain normal good condition. A problem immediately repaired.