From inside (document excerpt):
Product Data 58MVP Deluxe 4-Way Multipoise Direct-Vent Variable-Capacity Condensing Gas Furnace Series 140 Input Capacities: 40,000 thru 120,000 Btuh Comfort Heat TechnologyTM, the ultimate in heating comfort. The Carrier 58MVP WeatherMakerTM Infinity with Comfort Heat Technology achieves the optimum combination of comfort and efficency. The WeatherMaker Infinity achieves industry-leading ultra-high efficiency at up to 96.6 percent Annual Fuel Utilization Efficiency (AFUE).
Efficient performance is enhanced through the variable-capacity design. To maintain ideal comfort, Comfort Heat Technology automatically adjusts the heating level, maximizing the use of low heating levels that produce near silent furnace operation while meeting the exact heating needs. This unit is designed to keep the indoor temperature within 1 degree of the thermostat setpoint. Because it operates in low speed most of the time, the model 58MVP uses up to 80% less power than single-capacity furnaces. In addition to providing ultimate comfort, the model 58MVP has a sealed combustion system. This system brings combustion air from outdoors to the furnace and vents flue gases safely outside the home. Because it is sealed, operational noise is minimal. A sealed combustion system also means fewer cold drafts and less air infiltration. Quality materials are the key behind the model 58MVP’s outstanding performance. Carrier stands behind quality. We offer lifetime warranty protection* on the heat exchangers, the heart of the WeatherMaker Infinity. The Comfort Heat control center, the variable-speed inducer motor, and the variable-speed blower motor are all backed by a 5-year E 1999 Carrier Corporation Form 58MVP-8PD Limited Warranty. There is a 3-year Limited Warranty on hot surface ignition (HSI). The model 58MVP is available in 6 heat/airflow combinations. The unit has a 4-way multipoise design and can be installed in upflow, downflow, or horizontal positions covering up to 24 different applications. The versatile 4-way multipoise design in conjunction with variable capacity makes the 58MVP ideal for use with split-system cooling, including 2-speed units. A Carrier electronic air cleaner, humidifier, ThermidistatTM, comfort ventilator, and Comfort ZoneTM will provide year-round comfort and efficiency. Designed for durability, comfort, and reliability, the model 58MVP WeatherMaker Infinity is the ultimate in versatile, efficient comfort. Quality Registration — The 58MVP is engineered and manufactured under an ISO 9001 registered quality system. Venting — The combustion-air and vent pipes can terminate through a side wall or through the roof when used with a factory-authorized vent termination kit. Blower Access Panel Switch — Automatically shuts off 115-v power to furnace whenever blower access panel is opened. Reliable Heat Exchanger Design — The primary heat exchanger is made of aluminized steel for corrosion resistance. The patented SerpentuffTM condensing heat exchanger cells are laminated with polypropylene for greater resistance to corrosion and epoxy coated externally to prevent oxidation. This break-through in heating technology helps extend the life of the furnace for years of dependable performance. The heat exchanger is positioned in the furnace to extract additional heat. Warranty — The 58MVP heat exchangers come with a Limited Warranty for lifetime of original owner in single family residence