CONQUEST 80 - Page 86

)
-
YES
• RESTORE POWER TO UNIT
• IF CHECKS ARE OK, REPLACE IFC
-
• CHECK FOR 115 VAC ACROSS BLOWER
MOTOR AND BLOWER MOTOR TERMINALS
~REPLACE IFC IF
NO WIRING TO BLOWER
(HEAT AND NEUTRAL) ON IFC MOTOR IS OK
.YES
REPLACE BLOWER MOTOR
I
SYSTEM RUNS
NO
I NOTE: IF IFC GOES INTO LOCKOUT WAIT 30 SECONDS THEN
UNTIL CALL FOR
-
RESET SYSTEM
HEAT ENDS
I I
• CHECK CONTINUITY OF GROUND WIRE. NOTE: IF GROUND IS
YES
POOR OR ERRATIC, SHUTDOWN MAY OCCUR OCCASIONALLY EVEN
THOUGH OPERATION IS NORMAL AT THE TIME OF CHECKOUT.
• CHECK FLAME SENSE CURRENT
• CHECK FOR EXCESSIVE HEAT AT IGNITER BASE, (TEMP.
ABOVE 1000 F (538 C) CAUSES SHORT TO GROUND)
• TURN POWER OFF TO UNIT.
• CLEAN FLAME SENSOR WITH STEEL WOOL.
• RESTORE POWER TO UNIT.
'
• IF CHECKS ARE OK, REPLACE IFC
TURN THERMOSTAT TO OFF
• CHECK FOR PROPER THERMOSTAT OPERATION.
I
-
VALVE SHUTS OFF
• REMOVE VALVE LEAD AT IFC
FLAME GOES OUT
I I
NO
IF VALVE CLOSED, RECHECK THERMOSTAT AND
YES
WIRING. IF NOT, REPLACE VALVE.
• CHECK FOR OPEN LIMIT. ,
I
DRAFT MOTOR STOPS AFTER 5 SEC.
NO
-
REPLACEIFC
tYES
•
GAS VALVE OPENS AND
I
MAIN BURNER LIGHTS
YES
.
I
MAIN BURNER
REMAINS POWERED
AND LIT
I
NO
I
I
NO
I
YES
INDOOR BLOWER MOTOR
I
NO
ST ARTS 20 SECONDS
AFTER MAIN GAS VALVE OPENS
I I
INDOOR BLOWER MOTOR
STOPS AFTER
I
90/120/160/180 SECONDS
YES
I
TROUBLESHOOTING ENDS
I
NOTE:
REPLACE IGNITERl
SYSTEM WILL ATTEMPT TO LIGHT 4 TIMES.
VOLTAGE IS PRESENT AT THE VALVE FOR
ONLY 8 SECONDS DURING EACH TRIAL FOR
IGNITION (SYSTEM WILL GO INTO A 1-HOUR
LOCKOUT AFTER 4 TRIES). THE BLOWER AND
ICM WILL RUN 180 SEC. IF THE SECOND
IGNITION TRIAL FAILS TO SENSE FLAME.
• CHECK FOR 24 VAC ACROSS THE VALVE
AND VALVE TERMINALS ON THE IFC
f YES
• CHECK IGNITER POSITION.
I
• CHECK FOR GAS FLOW TO AND FROM VALVE.
f NO
REPLACE VALVE IF NO
I
FLOW THAU VALVE
NOTE: IF IFC GOES INTO LOCKOUT WAIT 30 SECONDS THEN
-
RESET SYSTEM
-
• CHECK POLARITY OF 115 VAC SUPPLY
• CHECK CONTINUITY OF GROUND WIRE
• CHECK INSULATION ON IGNITER LEADS
• CHECK FLAME SENSE CURRENT (YELLOW LED)
LED IS ON IF FLAME CURRENT IS GOOD,
IT FLASHES IF CURRENT IS MARGINAL.
• TURN POWER OFF TO UNIT
• CLEAN FLAME SENSOR WITH STEEL WOOL IF LED FLASHES
I
NO
-
-
• CHECK FOR OPEN LIMIT. ,
REPLACE IFC
I
REPEAT PROCEDURE UNTIL TROUBLEFREE
OPERATION IS OBTAINED.
STATIC DISCHARGE CAN DAMAGE INTEGRATED FURNACE CONTROL (IFC)
* "OK" LED BLINKS TO INDICATE EXTERNAL FAULTS:
(1) BLINK FOLLOWED BY A 2 SEC. PAUSE-1 HOUR LOCKOUT
(2) BLINKS FOLLOWED BY A 2 SEC. PAUSE - PRESSURE SWITCH IS OPEN
(3) BLINKS FOLLOWED BY A 2 SEC. PAUSE - LIMIT SWITCH IS OPEN
(4) BLINKS FOLLOWED BY A 2 SEC. PAUSE - PRESSURE SWITCH CLOSED
92-22744-10-03
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