I installed a F3 CB in my fireplace a couple years ago. I have been really happy with it and it continues to heat our upstairs all winter long with no issues. But I have been wondering about something for a little while: do clearances to non-combustible surfaces (it is installed in the firebox of the fireplace) still a concern? That is are there any safety concerns with not having the clearances being maintained despite being inside a fireplace alcove? The manual seems a little vague with regards to fireplace installation but I see you can get a short leg kit for fireplace installs. Thanks for any advice or help. I had a thread on here regarding my install a couple years ago with pictures but not sure how to reference it in this post.