Just leaving this as it may help someone else. I have 2 of these pellet stoves. One I purchased new and one used. I noticed the used stove was not burning as well as my newer one. I tried different fuels and always had the same thing, a lazy flame and lots of soothing. I put in a new combustion blower , the one in it had a loud noise, and this helped but I still had alot of sooting on the glass. I noticed no gasket visible under the fire pot so I ordered one and a new pot while I was at it. WOW what a difference. Heat output jumped from 250° all the way up to over 300. No more sooting either. Just thought this may help someone else seeing these problems.