Performed maintenance inspection on an inactive barn furnace that hasn't operated for several years. Discovered improper horizontal venting installation contrary to manufacturer specifications requiring vertical venting, and noted complete absence of ductwork and LP gas supply. Successfully tested ignition sequence to verify ignitor glow and gas valve operation. Recommended proper vertical venting installation per manufacturer requirements, addition of necessary ductwork, and suggested possible replacement with a hanging heater as potentially more suitable for the application.