United states stove company 6039 multi

[Bills6039]

Bought this for 350.00 (2007 Model) everything original except Agitator motor was shot so replaced that and gasket on combustion , we have about 1500sq ft in our place 2 level and insulated very well and I have to run this on at least Hr 5 just to keep it around 70 in here, which makes no sense at all, today went to lite it and every time I lite it within 5 min or so it would go out, (lighting it with pellets ) seemed like the combustion fan may not have been working , so I tried for almost 4 hours to get it to stay lite , tried less air with manual draft and more air , tried diff settings with draft fan and would still go out, almost like it was not getting enough air , AND I HAD JUST CLEANED IT GOOD. Finally I cranked Hr setting to 9 and lite it, and off it went, combustion fan made a high freq pitched sound for good hour or so and has quite and stove been running ever since , I have turned it down to Hr 5 and seems be working there with the manual dampner out about 1 3/4 " or more, but burning corn and it is caking up on the beater bar . Too much air with manual draft? You guys think the combustion blower is about shot , being I have to run it on such a high heat setting and the motor was making a noise ?