Here are some tips:① New vacuums may have a "new" smell that goes away after 3 months.② Check for damp dust stuck on the mop nozzle, since it can create odors. Remember to remove any wet dust after each use before storing your vacuum. The pre-filter, exhaust filter, or large dust separator may also start smelling if not dried completely. After a wash with water, dry the parts thoroughly in well-ventilated shade for at least 24 hours before using them again. ③ If you can smell the dust bag, strong odors like pet waste may have transferred to the dust bag. Replace the bag after vacuuming up strong-smelling items even if it is not full. Similarly, old dust bags that haven't been replaced in a long time may also start to smell. Replace the dust bag regularly even if it’s not full.