At 0941 hours Company 95 was dispatched to 201 Orchard Hills Drive to check for carbon monoxide in the residence, the homeowner was taken to the hospital for symptoms. Crews checked the residence and found levels above normal at the front door and high levels on the upper floor of the residence. The source was determined to be a coal fired stove that had been burning on previous days. The flue was blocked with ashes sending the carbon monoxide into the residence instead of going out the chimney. All of the ashes and burning coal was removed from the stove and the flue disconnected and cleaned out. Crews then ventilated the residence until the CO levels were safe.