From inside (document excerpt):
58MXA 4-Way Multipoise Fixed-Capacity Direct-Vent Condensing Gas Furnace Visit www.carrier.com Service and Maintenance Instructions For Sizes 040-140, Series 160 ELECTRICAL SHOCK, FIRE, OR EXPLOSION HAZARD Failure to follow safety warnings exactly could result in dangerous operation, serious injury, death, or property damage. Improper servicing could result in dangerous operation, serious indury, death, or property damage.
Before servicing, disconnect all electrical power to furnace. When servicing controls, label all wires prior to disconnecting. Reconnect wires correctly. Verify proper operation after servicing. A93040 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. FAILURE TO FOLLOW THIS WARNING COULD RESULT IN POSSIBLE DAMAGE TO THIS EQUIPMENT, SERIOUS PERSONAL INJURY, OR DEATH. ® ® ·· ·· ·· 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. 3. Paint thinners and other painting compounds, paper bags, or other paper products. Failure to follow this warning can cause corrosion of the heat exchanger, fire, personal injury, or death. NOTE: Read the entire instruction manual before starting the installation. This symbol indicates a change since the last issue. TABLE OF CONTENTS SAFETY CONSIDERATIONS .2 GENERAL 2 ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS 2 CARE AND MAINTENANCE .2 Cleaning and/or Replacing Air Filter .3 Blower Motor and Wheel Maintenance .3 Cleaning Burners 4 Cleaning Heat Exchangers 5 Primary Heat Exchangers 5 Secondary Heat Exchangers 6 U L A93007 Fig. 1–Multipoise Furnace in Upflow Orientation Flushing Collector Box and Drainage System 6 Servicing Hot Surface Ignitor 7 Electrical Controls and Wiring .8 Checking Heat Tape Operation (If Applicable) 8 Winterizing 10 WIRING DIAGRAM .11 TROUBLESHOOTING .11 Status Codes 11 Component Tests 11 Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations. Book 1 4 PC 101 Catalog No. 535-80028 Printed in U.S.A. Form 58MXA-8SM Pg 1 8-02 Replaces: 58MXA-7SM Tab 6a 8a EFFICIENCY RATING CERTIFIED AIRFLOW Ca ie rr r Cor pora UPFLOW ti on CERTIFIED IR REGISTERED QUALITY SYSTEM 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, and CAUTION. 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. Installing and servicing heating equipment can be hazardous due to gas and electrical components.