Carrier 58MCB Service And Maintenance Instructions

Also see for 58MCB: User's information manual Owner's manual Service and maintenance instruction Nstallation, start-up, and operating instructions Installation, start-up, and operating instructions

Contents

Carrier 58MCB Service And Maintenance Instructions Manual pdf 14 page image

14A99118Fig. 18 -- Inducer Housing Drain TubeComponent TestNOTE: The furnace control component test allows allcomponents to run for a short time; except the gas valve andhumidifier terminal HUM are not energized for safety reasons. TheEAC--1 terminal is energized when the blower is energized. Thisfeature helps diagnose a system problem in case of a componentfailure. The component test feature will not operate if anythermostat signal is present at the control and not until all timedelays are completed.NOTE: Record the status code BEFORE opening the bloweraccess door and before shutting off power to furnace. Opening theblower access door will open the blower door switch and shut offpower within the furnace. When power to the furnace is shut off byeither method, the status code will be lost because the code is notstored while power is removed for any reason.To Begin Component Self--Test:ELECTRICAL SHOCK AND UNIT MAY NOTOPERATE HAZARDFailure to follow this warning could result in electrical shock,personal injury, or death.Blower 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.! WARNING1. Remove blower access door.2. Disconnect the thermostat R lead from furnace controlboard.3. Manually close blower door switch.4. For approximately 2 sec, short (jumper) the COM--24v ter-minal on control to the TEST/TWIN 3/16--in. quick--con-nect terminal on control until LED turns off. Remove jump-er from terminals. (See Fig. 16.)NOTE: If TEST/TWIN and COM--24v terminals are jumperedlonger than 2 sec, LED will flash rapidly and ignore componenttest request.A99119Fig. 19 -- Funnel in Drain Tube and AntifreezeRunning Through TrapComponent test sequence for single--stage furnace is as follows:a. LED will display status code 11 four times.b. Inducer motor starts and continues to run until Step f. ofcomponent test sequence.c. After 7 sec the hot surface igniter is energized for 15sec, then off.d. Blower motor operates on HEAT speed for 10 sec.e. Blower motor operates on COOL speed for 10 sec.f. Inducer motor stops.5. Reconnect R lead to furnace control board, remove tapefrom blower door switch, and reinstall blower door.6. Operate furnace per instruction on outer door.7. Verify furnace shut down by lowering thermostat setting be-low room temperature.8. Verify that furnace restarts by raising thermostat settingabove room temperature.Use the Component Test to check furnace components for properoperation. To initiate the component self--test sequence, shut off theroom 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. Recordthis status 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, then de--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 ener-gized for safety reasons.58MCB