I've owned a Fireview for four years now and have been troubleshooting the same problem for as many years. There is an acrid smell that seems to come from above the loading door and the backside of the lid. The problem worsens when engaging the combustor and reducing the airflow to less than 1. Woodstock has not been able to solve the problem. What has been tried: 1. Extended the chimney height 2. Replaced the door gasket and lid gasket 3. Replaced the CAT 4. Adjusted the door tightness 5. Adjusted the airflow across the glass Any ideas of where to look next would be greatly appreciated.