Carrier 58MXA Instruction Manual

Also see for GAS FURNACE 58MXA: User's information manual User manual Service and maintenance instructions User's information manual User's information manual

Contents

6. Reconnect drain cap to inducer housing.7. Replace main furnace door.8. Propylene glycol need not be removed before restartingfurnace.WIRING DIAGRAMSee Fig. 16 for Wiring Diagram.TROUBLESHOOTINGUse the Troubleshooting Guide, the status code LED on thecotntrol and the Component Test to isolate furnace operationproblems.STATUS CODESFor an explanation of status codes, refer to service label located onback of main furnace door or Fig. 17 and the TroubleshootingGuide. The stored status code will NOT be erased from the controlmemory if 115- or 24-v power is interrupted.NOTE: Removing the blower access door will open the bloweraccess door switch and terminate 115-v power to the control.To read current status code, remove main furnace door. The statuscode LED can be viewed through the sight glass on the bloweraccess door.NOTE: NO thermostat signals may be present at control and allblower off delays must be completed to view previous codes.Make sure limit switch or flame rollout switch wire does notcontact any metal component, such as gas valve. If wire isshorted, 3-amp fuse on furnace control will blow.To retrieve previous codes, remove 1 of the red main limit or flamerollout switch wires for 1 to 4 sec until the LED light goes out, thenreconnect it. (Do not leave red wire disconnected for longerperiods of time as the control will assume an overtemperaturecondition exists and will respond with blower operation.) Thisplaces the control in the status recall mode and displays the lastcode stored in memory.Record the code. After the last code is displayed the control willperform the component test, and then return to normal standbymode.COMPONENT TESTBlower access panel door switch opens 115-v power tocontrol board. No component operation can occur. Cautionmust be taken when manually closing this switch for servicepurposes. Failure to follow this warning could result inelectrical shock, personal injury, or death.Use the Component Test to check furnace components for properoperation. To initiate the component self-test sequence, shut offthe room thermostat or disconnect the ″R″ thermostat lead. Briefly(approximately 2 sec) short the TWIN/TEST terminal to the COM24V terminal. The status LED will turn off. The test sequence willbe as follows:1. LED flashes last status code, or code 11, 4 times. Record thisstatus code for further troubleshooting.2. The inducer will start and continue to run until test is over.3. Hot surface igniter (HSI) is energized for 15 sec, thende-energized.4. Blower operates on continuous FAN speed for 10 sec, thenturns off.5. The blower motor operates on HEATING speed for 10 sec,then turns off.6. The blower motor operates on COOLING speed for 10 sec,then turns off.7. Inducer turns off.8. The gas valve and humidifier terminal HUM are not energizedfor safety reasons.11→→