From inside (document excerpt):
58CTA/CTX PERFORMANCE 80 TWO-STAGE 4-WAY MULTIPOISE INDUCED-COMBUSTION FURNACE Input Capacities: 45,000 thru 155,000 Btuh Product Data THE PERFORMANCE 80 GAS FURNACE The 58CTA/CTX Two-Stage, 4-way Multipoise Gas Furnaces offer unmatched comfort in their class with ComfortHeatt technology in an 80% AFUE gas furnace. You get the benefits of a ComfortHeatt technology furnace: reduced drafts, reduced sound levels, longer cycles, less temperature swings between cycles, and less temperature differences between rooms.
Its exclusive, intelligent microprocessor control adapts to the heating needs of the home by automatically adjusting high and low heat times to maximize comfort. The 58CTA/CTX furnaces are approved for use with natural or propane gas, and the 58CTX is approved for use in Low NOx Air Quality Management Districts. STANDARD FEATURES S ComfortHeatt Technology Intelligent microprocessor control S Two-stage heating with single-stage thermostat with patented Adaptive Control Technology S Very low operating sound through low-stage operation and QuieTecht system SmartEvapt-Humidity control when using a Thermidistatt/ Infinityt control Comfort Fant adjustable constant fan speed from the thermostat S High-Efficiency Media Filtration Cabinet included S Microprocessor based control center LED diagnostics and self test feature Stores fault codes during power outages Adjustable heating air temperature rise Adjustable cooling airflow S 4-way Multipoise furnace, 13 vent applications S Compact design – only 33-1/3 in. (847 mm) tall S Power Heatt Igniter S Draft Safeguard switch to ensure proper furnace venting S Insulated blower compartment S Inner door for tighter sealing S HYBRID HEATr Dual Fuel System compatible S All models are Chimney Friendly when used with accessory vent kit S Twinning in Upflow, Downflow and Horizontal S Residential installations eligible for consumer financing through the Retail Credit Program A04041 58CTA/CTX A02169 A02238 A02170 HEAT EXCHANGER CONTROL BOARD INDUCER BLOWER MODEL NUMBER NOMENCLATURE 58CTA 58CTA Two-Stage 4-Way Multipoise 58CTX Low NOx version 045 100 08 Nominal Cooling Size (Airflow at .5 e.s.p.) (400 CFM per 12,000 Btuh) 08 800 CFf7 12 1200 CFM 14 1400 CFM 16 1600 CFM Input Capacity 045 44,000 Btuh 070 66,000 Btuh 090 88,000 Btuh 110 110,000 Btuh 135 132,000 Btuh 155 154,000 Btuh Series Number 20 2000 CFM 22 2200 CFM EFFICIENCY RATING CERTIFIED MEETS DOE RESIDENTIAL CONSERVATION SERVICES PROGRAM STANDARDS.