Hi i was amazed when i opened my ef3 stove yesterday and looked at the heat tubes and found a blackish tar color on the tubes and it wass hard to scrap off.The funny thing is i just did a complete teardown and complete cleaning about a mont prior to heating season.I have only burned 4 bags of eastern embers pellets so far.Why would the tubes have this on them now usually they have a light power of dust which i clean by pulling on the rod about 3 or 4 times.I posted in previous topics that i was getting a smell in my house of wood burning smell.I checked all my pipes re-siliconed retaped joints i even put on a new exaust motor gasket.I still get a smell when it going-not really strong but there anyway and when i go to basement and come back upstairs i smell it again so its there.Itried looking for a leak with lights out and flashlight-no smoke that i can see.What i did do was put my trouble light inside the burn chamber -turn it on and look for light throught tubes-i did not see light- but i saw light where the scraper tube has access to the stove.when you pull on the scraper handle there is a lil gap but that needs to be there for the movement of the scraper.Can the smell i have be coming out of that hole?It cant be sealed because the bar need to move.Any input would be great and thanks again everyone for all suggestions.