From inside (document excerpt):
58HDX 4 WAY MULTIPOISE FIXED SPEED CONDENSING GAS FURNACE Service Guide TABLE OF CONTENTS PAGE SAFETY CONSIDERATIONS . 1 CERTIFIED ama GENERAL . 2 ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS. 2 CARE AND MAINTENANCE . 3 Cleaning and/or Replacing Air Filter 3 Blower Motor and Wheel Maintenance 3 Cleaning Burners . 4 Cleaning Heat Exchangers . 15 Primary Heat Exchangers 15 Secondary Heat Exchangers 15 Flushing Collector Box and Drainage System 15 Servicing Hot Surface Igniter .
16 Electrical Controls And Wiring . 18 Checking Heat Tape Operation (If Applicable) . 18 Winterizing 18 WIRING DIAGRAM 18 TROUBLESHOOTING 18 NOTE: Read the entire instruction manual before starting the installation ! ELECTRICAL HAZARD WARNING SHOCK, FIRE, OR EXPLOSION Failure to follow warnings could result in personal injury, death, or property damage. Before servicing, disconnect all electrical power and gas supply to furnace. Lockout and tag with appropriate label. When servicing controls, label all wires prior to disconnecting. Reconnect wires correctly. Verify proper operation after servicing. ! ELECTRICAL HAZARD WARNING SHOCK, FIRE OR EXPLOSION SAFETY CONSIDERATIONS Recognize safety information. This is the safety-alert symbol. ! When you see this symbol on the furnace and in instructions or manuals, be alert to the potential for personal injury. Understand the signal words DANGER, WARNING, CAUTION, and NOTE. These words are used with the safety-alert symbol. DANGER identifies the most serious hazards which will result in severe personal injury or death. WARNING signifies hazards which could result in personal injury or death. CAUTION is used to identify unsafe practices which would result in minor personal injury or product and property damage. NOTE is used to highlight suggestions which will result in enhanced installation, reliability, or operation. Failure to follow this warning could result in property damage, personal injury, or death. The ability to properly perform maintenance on this equipment requires certain expertise, mechanical skills, tools, and equipment. If you do not possess these, do not attempt to perform any maintenance on this equipment other than those procedures recommended in the User’s Manual. 1 ! WARNING ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS FIRE / EXPLOSION HAZARD Failure to follow this warning could cause personal injury, death, or property damage. Never store anything on, near, or in contact with the furnace, such as: 1. Spray or aerosol cans, rags, brooms, dust mops, vacuum cleaners, or other cleaning tools. 2. Soap powders, bleaches, waxes or other cleaning compounds, plastic or plastic containers, gasoline, kerosene, cigarette lighter fluid, dry cleaning fluids, or other volatile fluids.