58MXA4-Way Multipoise Fixed-CapacityDirect-Vent Condensing Gas FurnaceService and Maintenance InstructionsFor Sizes 040-140, Series 170NOTE: Read the entire instruction manual before starting theinstallation.This symbol → indicates a change since the last issue.ELECTRICAL SHOCK, FIRE, OR EXPLOSIONHAZARDFailure to follow safety warnings exactly could result indangerous operation, serious injury, death, or property dam-age.Improper servicing could result in dangerous operation,serious injury, death, or property damage.- Before servicing, disconnect all electrical power to furnace.- When servicing controls, label all wires prior to disconnect-ing. Reconnect wires correctly.- Verify proper operation after servicing.ELECTRICAL SHOCK, FIRE OR EXPLOSIONHAZARDFailure to follow this warning could result in possible damageto this equipment, serious personal injury, or death.The ability to properly perform maintenance on this equip-ment requires certain expertise, mechanical skills, tools, andequipment. If you do not possess these, do not attempt toperform any maintenance on this equipment other than thoseprocedures recommended in the User’s Manual.FIRE OR EXPLOSION HAZARDFailure to follow this warning could cause corrosion of heatexchanger, fire, 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, vacuumcleaners, or other cleaning tools.2. Soap powders, bleaches, waxes or other cleaning com-pounds, plastic or plastic containers, gasoline, kerosene,cigarette lighter fluid, dry cleaning fluids, or other volatilefluids.3. Paint thinners and other painting compounds, paper bags,or other paper products.TABLE OF CONTENTSSAFETY CONSIDERATIONS .....................................................1GENERAL......................................................................................2ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS........2CARE AND MAINTENANCE.....................................................3Cleaning and/or Replacing Air Filter.......................................3Blower Motor and Wheel Maintenance...................................4Cleaning Burners ......................................................................5Cleaning Heat Exchangers........................................................5Primary Heat Exchangers ......................................................5Secondary Heat Exchangers ..................................................6Flushing Collector Box and Drainage System ........................6Servicing Hot Surface Igniter...................................................8Electrical Controls and Wiring.................................................8Checking Heat Tape Operation (If Applicable) ......................9Winterizing................................................................................9WIRING DIAGRAM.....................................................................9TROUBLESHOOTING .................................................................9Status Codes..............................................................................9Component Tests ....................................................................11SAFETY CONSIDERATIONSRecognize safety information. This is the safety-alert symbol .When you see this symbol on the furnace and in instructions ormanuals, 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 insevere personal injury or death. WARNING signifies hazardswhich could result in personal injury or death. CAUTION is usedto identify unsafe practices which may result in minor personalinjury or product and property damage. NOTE is used to highlightsuggestions which will result in enhanced installation, reliability,or operation.A93040Visit www.carrier.comManufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.Book 1 4Tab 6a 8a PC 101 Catalog No. 535-80142 Printed in U.S.A. Form 58MXA-10SM Pg 1 9-04 Replaces: 58MXA-9SM