FIGURE 33
INTEGRATED FURNACE CONTROL (IFC) TROUBLESHOOTING GUIDE
FOR UTEC 1012-920 & HONEYWELL S9201E2001 (115 VAC IGNITER)
START
1. SET FAN SWITCH TO AUTO
2. SET THERMOSTAT TO
CALL FOR HEAT
INDUCED DRAFT MOTOR
(IDM) STARTS
30 SEC. PREPURGE
IGNITER WARMS UP
AND GLOWS RED
34 SECONDS WARMUP
MAIN BURNER
LIGHTS
• REMOVE (IFC) COVER, CHECK LIGHTS
POWER LED ON • CHECK LINE VOLTAGE POWER
• CHECK LOW VOLTAGE TRANSFORMER
MICROPROCESSOR STATUS LED ON REPLACE (IFC)
NOTE: “OK” LED WILL FLASH TO
INDICATE TWINNING CIRCUIT FAULTS.
CHECK FOR 24 VAC FROM CHECK THERMOSTAT
TERMINAL “W” TO “C” ON IFC WIRING
• CHECK LIMITS, (CLOSED)
• CHECK WIRING
• CHECK PRESSURE SWITCH, (OPEN) REPLACE SWITCH
IF THE PRESSURE SWITCH DOESN’T
CLOSE WITHIN 60 SEC. THE IDM WILL
STOP FOR 5 MIN. AND RETRY
• CHECK FOR 115VAC TO IDM MOTOR REPLACE (IFC)
IF WIRING TO
IDM MOTOR IS OK
REPLACE IDM MOTOR
• CHECK FOR BLOCKED VENT REPLACE SWITCH
• CHECK AIR PROVING SWITCH (CLOSED)
• CHECK WIRING TO IGNITER REPLACE (IFC)
• CHECK FOR 115 VAC AT IGNITER, IF WIRING TO
TERMINALS AND AT (IFC) TERMINALS IGNITER IS OK
REPLACE IGNITER
SYSTEM WILL ATTEMPT TO LIGHT 4 TIMES. VOLTAGE IS PRESENT
AT THE VALVE FOR ONLY 9 SECONDS DURING EACH TRIAL FOR
IGNITION (SYSTEM WILL GO INTO A 1-HOUR LOCKOUT AFTER
4 TRIES). THE BLOWER AND INDUCED DRAFT BLOWER WILL RUN
180 SEC. IF THE FIRST IGNITION TRIAL FAILS TO SENSE FLAME
• CHECK FOR 24 VAC ACROSS THE VALVE AND
VALVE TERMINALS ON THE (IFC)
• CHECK IGNITER POSITION
• CHECK FOR GAS FLOW TO AND
FROM VALVE
REPLACE VALVE REPLACE (IFC)
IF WIRING TO
VALVE IS OK
37
WARNING
DISCONNECT POWER BEFORE
SERVICING.
SERVICE MUST BE BY A TRAINED,
QUALIFIED SERVICE TECHNICIAN.
HAZARDOUS VOLTAGE
LINE VOLTAGE
CONNECTIONS
FLOW CHART CONTINUED ON NEXT PAGE
NO
NO
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NO
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NO
NO
YES
YES
YES
YES
YES
YES
YES
NO
YES
NO
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NO
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