Tones dropped at 2033 for a fire in a sugar house at 2043 State Highway 68, the Cooperative Extension Learning Farm. Engine 7 and TA-20 were on the road shortly after with 4-1 and 4-2 responding to the scene. Upon arrival the chiefs reported that the fire was put out with a drychem extinguisher, but continue to respond code 3 due to heavy smoke. On arrival interior SCBA crews were sent in due to smoke conditions to overhaul the oil-fired sap evaporator that had caught fire due to an oil burner malfunction. After removing some of the bricks and insulation the temperature rose above the ignition point of the oil, re-igniting the oil soaked bricks and insulation. The oil continued to flow into the boiler until the tank could be disconnected due to a faulty shut off valve. Finally the fire had to be doused with water cans and 1-3/4” hose. No damage was sustained to the building as the fire was contained to the evaporator. The overhaul was finished and crews were placed back in service with no injuries or equipment lost.