58MXBDeluxe 4–Way MultipoiseFixed-Capacity Condensing Gas FurnaceInstallation, Start-Up, and Operating InstructionsSizes 040-140, Series 100NOTE: Read the entire instruction manual before starting theinstallation.NOTE: This furnace can be installed as a (2-pipe) direct ventor (1-pipe) non-direct vent condensing gas furnace.This symbol → indicates a change since the last issue.TABLE OF CONTENTSSAFETY CONSIDERATIONS .....................................................2CODES AND STANDARDS........................................................4ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS........6INTRODUCTION ..........................................................................6APPLICATIONS............................................................................6General ......................................................................................6Upflow Applications.................................................................6Downflow Applications ............................................................8Horizontal Left (Supply-Air Discharge)Applications ............................................................................10Horizontal Right (Supply-Air Discharge)Applications ............................................................................11LOCATION..................................................................................14General ....................................................................................14Furnace Location Relative to Cooling Equipment ................15Hazardous Locations...............................................................15Furnace Location and Application .........................................15AIR FOR COMBUSTION AND VENTILATION ....................16INSTALLATION .........................................................................19Leveling Legs (If Desired) .....................................................19Installation in Upflow and DownflowApplications ............................................................................19Installation in Horizontal Applications ..................................19Air Ducts.................................................................................21General Requirements .......................................................21Ductwork Acoustical Treatment .......................................21Supply Air Connections ....................................................21Return Air Connections.....................................................21Filter Arrangement..................................................................22Bottom Closure Panel.............................................................23Gas Piping...............................................................................23Electrical Connections ............................................................24115–v Wiring.....................................................................2524–v Wiring.......................................................................26Accessories ........................................................................26Removal of Existing Furnaces from CommonVent Systems ..........................................................................27Combustion Air and Vent Pipe Systems ...............................27Condensate Drain....................................................................41General...............................................................................41Application.........................................................................42Condensation Drain Protection .........................................42START-UP, ADJUSTMENTS AND SAFETY CHECK ...........42General ....................................................................................42Prime Condensate Trap With Water ......................................43Purge Gas Lines......................................................................43Sequence of Operation............................................................43Heating Mode ....................................................................44Cooling Mode ....................................................................44Thermidistat Mode ............................................................44Continuous Blower Mode .................................................47Heat Pump Mode...............................................................47Component Test.................................................................51Adjustments.............................................................................51Set Gas Input Rate ............................................................51Set Temperature Rise ........................................................55Adjust Blower Off Delay (Heat Mode)............................55Set Thermostat Heat Anticipator ......................................55Check Safety Controls ............................................................56Check Primary Limit Control ...........................................56Check Pressure Switch ......................................................56Checklist..................................................................................56A93040Visit 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 Printed in U.S.A. Catalog No. 58MXB-1SI Pg 1 8-05 Replaces: 58MXA-18SI