Doing the setup on my new nc30 this weekend and have decided to do things differently. Will be running 28" of 6" vertical to a 6" T then 8" into my thimble. Knocked down my old block flue and installed a 20' by 6" double wall setup. My thought of using the T in place of the 90 off the stove is ease of cleaning and better draw. Anyway just wanted to hear any other thoughts or input.