Too Many Coals???

[venator260]

It also bears mentioning, be absolutely sure your ash plug is secure before loading the stove back up.

 

[Zack R]

I've had the same issue recently due to the cold temps (-4F this morning, -11F a few days ago) and pushing the stove harder.

Open up the air control and let them burn down to ash before the next reload. You'll lose max heat output for a few hours but can catch up with a full load once there is room for it in the firebox.