Your Evergreen air freshener requires minimal maintenance. Every 6 months, you should place a few drops of sewing machine oil or silicone spray on the axle in the motor. Do NOT use fast evaporating products like the classic “WD-40” which is more of a cleaner than a lubricant and it will dry out the motor… WD-40 does have some lubricants as well as their classic nut and bolt unlock. You may use any brand of lubrication that you want… just be sure that it is a lubricant. If the machine ever makes noise or the fan stops running, it probably needs to be oiled.