Upon arrival, a smell similar to skunk was noticeable. Inspected furnace and humidifier for any issues. None found. Tested gas line with combustible gas detector and found a confirmed leak at or near the union to the fireplace. Was also getting elevated readings near the Tee at where the main line comes into the house, aswell as at or near the Tee where the gas line for the furnace splits off. Recommend calling a plumber for further leak detection and leak repairs. Westin Air recommends D&L Plumbing.