I'm currently getting a lesson in the effect of increased draft due to low outside temps. My IR thermometer says the Matrix insert is a bit over 800F right now, less than an hour after loading it for the night. I closed down the air when it was much cooler, but the temp has continued climbing anyhow. What does one do in this situation? Edit: to clarify, the temp. was measured on top of firebox, through the air vent.