This course emphasizes the operation, maintenance, testing and repairing of residential furnaces. Gas and oil furnaces will be covered. The learner will use hand tools and test instruments. Topics include combustion, combustion safety, venting, filters, thermostats, heat transfer, gas piping, and carbon monoxide, circulation blowers, gas conversion, furnace components and function and typical location. HVACR is a common reference to Heating, Ventilation, Air Conditioning and Refrigeration.