I cleaned my flue for the first time this weekend and it was mostly successful. I say mostly, because afterwards, when I started a fire in the fireplace insert (a Lennox Performer C210), it started smoking up everything. So...I have apparently not cleaned it quite as well as I thought. I think that not all of the creosote fell into the firebox and has remained somewhere in the system. I have a 6" SS flue liner that was installed along with the insert. What do I still need to do to finish this project off?