Heat Controller A-13 installation instructions Furnace Troubleshooting Guide

FURNACE TROUBLESHOOTING GUIDE

(COMBINATION HEATING AND COOLING UNITS WITH DIRECT SPARK IGNITION)

! WARNING

HAZARDOUS VOLTAGE	DISCONNECT POWER BEFORE
LINE VOLTAGE CON-	SERVICING.
NECTIONS	SERVICE MUST BE BY A TRAINED,
	QUALIFIED SERVICE TECHNICIAN.

START

SET THERMOSTAT TO

CALL FOR HEAT

SET FAN SWITCH TO AUTO

YES

INDUCED DRAFT BLOWER

MOTOR STARTS

YES

NO

•CHECK LINE VOLTAGE TO CONTROL BOARD

•CHECK LOW VOLTAGE TRANSFORMER

•CHECK WIRING

•CHECK FOR 208-230 VAC TO IOM MOTOR

YES

NO

REPLACE INTEGRATED CONTROL BOARD (IFC)

15 SECOND PREPURGE

YES

REPLACE INDUCED

DRAFT BLOWER

REPLACE IGNITOR/

CABLE ASSEMBLY

• CHECK NEGATIVE PRESSURE

IGNITOR SPARKS

YES

NO

•CHECK IGNITOR CABLE

•CHECK SPARK IGNITOR POSITION AND CONDITION

•IS NEGATIVE PRESSURE SWITCH CLOSED?

•CHECK FOR OPEN ROLL-OUT CONTROL

•CHECK FOR OPEN LIMIT

•CHECK IGNITION CONTROL CHASSIS GROUND WIRE

•CHECK WIRING

YES

NO

YES

YES

SWITCH SENSING TUBE

• CHECK FOR EXHAUST

BLOCKAGE

NO

REPLACE NEGATIVE

PRESSURE SWITCH

CHECK FOR EXHAUST,

INTAKE OR HEAT

EXCHANGER BLOCKAGE

NO

REPLACE IGNITION CON-

TROL

AND RESET CONTROL

REPLACE LIMIT

IF UNIT IS COLD

MAIN BURNER LIGHTS

YES

NOTE: THE SYSTEM WILL ATTEMPT TO LIGHT 3 TIMES WITH A 60 SECOND INTER-

PURGE BETWEEN TRIES. IF AFTER THE THIRD TIME THE BURNERS

DO NOT LIGHT, THE SYSTEM WILL LOCK OUT. IF THE UNIT IS EQUIPPED WITH A UNITED TECH. OR JOHNSON CONTROLS IGNITION CONTROL, THE SYSTEM WILL ATTEMPT TO LIGHT 3 TIMES EACH HOUR UNTIL THE BURNERS LIGHT OR THE THERMOSTAT IS RESET.

NO
• CHECK INLET GAS PRESSURE		REPLACE INTEGRATED
	NO
• CHECK 24 VOLTS TO GAS VALVE		CONTROL BOARD (IFC)
		IF WIRING IS OK
• CHECK FOR GAS FLOW TO AND FROM VALVE
• CHECK BURNER CARRYOVER
YES

REPLACE VALVE

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