ICP 9MAC/E series Troubleshooting Manual

Contents

ICP 9MAC/E series Troubleshooting Manual Manual pdf 7 page image

- 7 -SERVICE/STATUS CODE INSTRUCTIONSIf status code recall is needed disconnect the “R” thermostat lead, reset power, and put setup switch “SW1-1” in the ON position. To clear the statuscode history put setup switch “SW1-1” in the ON position and jumper thermostat terminals “R”, “W/W1”, and “Y/Y2” simultaneously until theHeartbeat flashes.LED CODE STATUSCONTINUOUS OFF - Check 115 VAC at L1 and L2, 24 VAC at SEC-1 and SEC-2, and 24V fuse.HEARTBEAT - (bright-dim-bright-dim) Control has 24 VAC power.ON SOLID - The control is locked out and will auto reset after 1 hour. Lockout could be due to any of the following:- Flame sense circuit failure.- Gas valve relay stuck open.- Software check error.Reset power to clear lockout. Replace control if status code repeats.EACH OF THE FOLLOWING STATUS CODES IS A SINGLE OR TWO DIGIT NUMBER WITH THE FIRST NUMBER DETERMINEDBY THE NUMBER OF SHORT FLASHES AND THE SECOND NUMBER AFTER THE (+) SIGN IS THE NUMBER OF LONGFLASHES.2 PRESSURE SWITCH DID NOT OPEN – Check for:- Obstructed pressure tubing.- Pressure switch stuck closed.3 LOW PRESSURE SWITCH DID NOT CLOSE OR REOPENED – Indicates the low pressure switch input failed to close on a call forheat, or opened during minimum-heat. If opens during blower on-delay period, blower will come on for the selected blower off-delay. Ifopens within 5 minutes after ignition the next heating cycle will be restricted to maximum-heat. Check for:- Proper vent sizing.- Air leak between vestibule and blower compartment.- Restricted vent.- Plugged condensate drain.- Low inlet gas pressure (if LGPS used).- Excessive wind. If problem persists turn setup switch “SW1-3” ON to boost inducer speed.- Improper pressure switch wiring.- Failed or “Out-of-Calibration” pressure switches.- Water in vent piping, possible sagging pipe.- Disconnected or obstructed pressure tubing.4 LIMIT CIRCUIT FAULT – Indicates the limit, or flame rollout is open or the furnace is operating in maximum-heat only mode due to 2successive limit trips while operating at any rate less than or equal to 71% of maximum rate. Blower will run at intermediate heat airflowfor 4 minutes or until open switch remakes whichever is longer. If open longer than 3 minutes, code changes to lockout #7. If open lessthan 3 minutes status code #4 continues to flash until blower shuts off. Flame rollout switch requires manual reset. Check for:- Loose blower wheel.- Defective switch or connections.- Improper minimum- or maximum-heat gas input adjustment.- Dirty filter or restricted duct system.- Improper limit switch or no limit gasket.5 ABNORMAL FLAME-PROVING SIGNAL – Flame is proved while gas valve is de-energized. Inducer will run until fault is cleared.Check for:- Leaky gas valve.- Stuck-open gas valve.6 IGNITION PROVING FAILURE – Control will try three more times before lockout #6 + 1 occurs. If flame signal is lost during bloweron-delay period, blower will come on for the selected blower off-delay. Check for:- Low inlet gas pressure.- Control ground continuity.- Gas valve defective or turned off.- Defective Hot Surface Igniter.- Manual valve shut off.- Oxide buildup on flame sensor (clean with fine steel wool).- Proper flame sense micro amps (.5 micro amps DC min., 4.0 – 6.0 nominal).- Green/Yellow wire MUST be connected to furnace sheet metal.- Inadequate flame carryover or rough ignition.- Flame sensor must not be grounded.7 LIMIT CIRCUIT LOCKOUT – Lockout occurs if the limit, or flame rollout switch is open longer than 3 minutes or 10 successive limittrips occurred during maximum-heat. Control will auto reset after 3 hours. Refer to status code #4.440 08 4001 00