VC Encore chimney height and other questions

I have a VC Encore 2550 the owners manual says the chimney should be 16' for 6" pipe. I am using 8" straight up and don't know how high the chimney should be. The stove was installed 4 years ago and seems to work OK, however the chimney is 7' above the peak of my single story roof. Also, for the life of me I cant find the secondary air probe behind the refractory access panel, or is it below the catalytic combustor. Someone mentioned that the cat should glow, the cat is covered, how do you know it is glowing?
Thanks
Kevin

Welcome Kevin,

I have a Encore NC with 8" diameter. The total flue length is 19 feet. It works great. I use griddle top and a flue surface thermometers. However...

Since you have a cat version, check the owners manual or call a good VC dealer with your question, if you don't get an answer here. Search also for previous threads on this subject.

Lots of great advice here. Burn wisely and safely!