I have a St Croix pellet stove. I got it last year to replace a 20-year-old pellet stove. This new St Croix stove has the pipe coming out the bottom of the back of the stove. (My old pellet stove's pipe came out the top of the stove.) Last year when using the St. Croix stove my house filled with smoke once and I also had my carbon detector go off. This was so disturbing I have not used the pellet stove since. (A knee-jerk expensive reaction.) I am ready to have a go at it again and I am wondering if my set up is all wrong. I am thinking that my pipe is full of ash and that caused the smoke and carbon. The pipe comes out the bottom back of the stove and then goes up about four feet to go out to my chimney. Would that cause the pipe to fill with ash? I never had any problems with my pipe or chimney with my old pellet stove. Any advice is most welcome. Thank you.