Proudly American
Describe a single event in its actual order
Reconstruct the event from memory. Did smoke appear before the door moved, at the first opening, or only when a new log went in? Was there visible smoke at the frame after the door was shut? Include any alarm, exhaust appliance already in use and recent changes in performance. In an active smoke or carbon monoxide emergency get everyone outside and call emergency services. Do not light another fire to provide a demonstration.
Get the operating instructions for this insert
A wood insert may have an air control, bypass or other device with model-specific loading instructions. An inherited note about the flue damper of the old open fireplace may describe hardware that the present insert does not use. Bring the model and manual if available. The provider can then distinguish an operating-sequence question from a possible issue with the vent route, a component above the fire or air entering from the room.
Tell the provider what has already changed
A recent door-seal replacement, a sweep or a change to wood supply can be relevant, but the most recent event does not establish the cause. Keep receipts separate and identify what was replaced or accessed. If the recommendation is to clean the passage, ask what points to a deposit. If further appliance service is recommended, ask which finding points to the appliance instead. That distinction helps avoid a repeat complaint after paying for an unrelated task.
Know what conclusion the visit can support
The visit may establish a physical restriction or mismatch, or it may identify unresolved factors that need further evaluation by an appliance or building ventilation specialist. Ask for the reason use should remain suspended and who will verify readiness after any work. An open loading door on a warm box is not a diagnostic tool for the homeowner.