Pellet stove insert pipe length too long?

[dandb819]

Ok trying to figure this out, I installed an older Earth stove pellet stove in our basement and it is 30 feet from the stove to the chimney cap. This stove is a positive pressure not a negative pressure stove and if i open up the damper on it to get a cleaner burn it will push some smoke out the hopper. This is a bottom feed stove and it will push it through the auger tube into the metering cup and through the hopper. If i leave the damper half shut it does not do this but it is running rich. To my knoledge with this being a positive pressure stove i must have too much back pressure with the length of pipe up the chimney. So is it possible to shorten up the length of the pipe run since it is in a lined flue already?

 

[jtakeman]

Sounds like it is a 3" vent.

Even though its lined they still recommend the full run. Probably have to increase to 4" vent.

 

[littlesmokey]

Do you have an alternative for the venting, say direct vent? Seems like you are pushing the limits of the stove and need a compromise somewhere.

 

[dandb819]

Well what i have is 3 inch for the first 18 feet and then the last 7 feet I have four inch. I did this just due to already having the three inch and enough four inch pipe on hand to finish the run. I thought that since i was going from the three inch to the larger four inch that it would help draw it up the flue. I really dont want to have to run the 4 inch all the way up if at all possible. It sounds like that is going to be the only way to do it i just thought that since it was already going up 18 feet that if i took off the four inch part it might draw better but it sounds like it is not a good idea to not have the liner all the way up.