From inside (document excerpt):
Product Data 58MSA 4-Way Multipoise Fixed-Capacity Condensing Gas Furnace Input Capacities: 40,000 thru 120,000 Btuh High Efficiency and Flexibility Designed to Meet the Needs of New Homes The model 58MSA combines high efficiency with flexibility to meet the changing needs of new home construction. The unique 4-way, multipoise design of the 58MSA allows for installation in upflow, downflow, horizontal left, and horizontal right orientations, meaning it is perfect for a variety of installation applications.
The furnace is factory configured for upflow application but can easily be made ready for downflow or horizontal installation. Horizontal applications offer the advantage of reduced space requirements by locating the furnace in an attic or crawlspace, freeing space formerly dedicated to a furnace or utility room. The 58MSA is specifically designed to meet the needs of home builders and new home owners. Home builders benefit from the 58MSA’s unmatched flexibility and by building a reputation of using quality appliances in homes. Home owners benefit by energy savings from one of the most important home appliances. The components of the 58MSA represent the finest in the industry. Hot surface ignition (HSI) and an integrated control center provide reliable and efficient ignition. The inducer and inducer motor are unique in that efficient operation is achieved in any type of installation. Standard PVC pipe is used to provide combustion air to the furnace and 2002 Carrier Corporation Form 58MSA-4PD vent the exhaust outdoors. The primary and secondary heat exchangers are backed by a 20-year Limited Warranty. The 58MSA is a standard part of a quality-built new home. This highefficiency furnace will provide years of quality service to home builders and home owners alike. As with other Carrier furnaces, this model is designed to work as a part of the total home comfort system which includes elements for cooling, air cleaning, humidification, ventilation, and zoning. 58MSA FEATURES/ BENEFITS Casing — One piece, seamless wraparound construction of heavy, prepainted galvanized steel resists corrosion. Certifications — The 58MSA units CSA (A.G.A. and C.G.A.) design certified for use with natural and propane gases. The furnace is factoryshipped for use with natural gas.