Sugar Shack and Evaporator Setup

What happens here

The creator moves into a 'sugar shack,' a small building dedicated to boiling down the sap. Inside, a large, custom-built evaporator is shown. He opens the main firebox door to reveal a roaring wood fire, which provides the heat for evaporation. He also points out a fan positioned to enhance airflow to the fire and mentions that used waste oil is sometimes employed to fuel the system, likely for starting or maintaining the heat.

Goal: Inspect the boiling setup