Bryant 581A operation manual Heating Service Analysis, Problem Cause Remedy

Table 35 — Heating Service Analysis

PROBLEM	CAUSE	REMEDY
Burners Will Not Ignite.	Misaligned spark electrodes.	Check flame ignition and sensor electrode positioning.
		Adjust as needed.
	No gas at main burners.	Check gas line for air; purge as necessary. After purging gas line of
		air, allow gas to dissipate for at least 5 minutes before attempting to
		relight unit.
		Check gas valve.
	Water in gas line.	Drain water and install drip leg to trap water.
	No power to furnace.	Check power supply, fuses, wiring, and circuit breaker.
	No 24 v power supply to control circuit.	Check transformer. Transformers with internal overcurrent protection
		require a cool-down period before resetting. Check 24-v
		circuit breaker; reset if necessary.
	Miswired or loose connections.	Check all wiring and wire nut connections.
	Burned-out heat anticipator in thermostat.	Replace thermostat.
	Broken thermostat wires.	Run continuity check. Replace wires if necessary.
Inadequate Heating.	Dirty air filter.	Clean or replace filter as necessary.
	Gas input to unit too low.	Check gas pressure at manifold. Clock gas meter for input. If too low,
		increase manifold pressure or replace with correct orifices.
	Unit undersized for application.	Replace with proper unit or add additional unit.
	Restricted airflow.	Clean filter, replace filter, or remove any restrictions.
	Blower speed too low.	Install alternate motor, if applicable, or adjust pulley to increase fan
		speed.
	Limit switch cycles main burners.	Check rotation of blower, thermostat heat anticipator settings, and
		temperature rise of unit. Adjust as needed.
	Too much outdoor air.	Adjust minimum position.
		Check economizer operation.
Poor Flame Characteristics.	Incomplete combustion (lack of combustion air)	Check all screws around flue outlets and burner compartment.
	results in:	Tighten as necessary.
	Aldehyde odors, CO, sooting flame, or floating flame.	Cracked heat exchanger.
		Overfired unit — reduce input, change orifices, or adjust gas line or
		manifold pressure.
		Check vent for restriction. Clean as necessary.
		Check orifice to burner alignment.
Burners Will Not Turn Off.	Unit is locked into Heating mode for a one minute min-	Wait until mandatory one minute time period has elapsed or power to
	imum.	unit.

Table 36 — IGC Board LED Alarm Codes

LED FLASH		DESCRIPTION	ACTION TAKEN BY	RESET METHOD	PROBABLE CAUSE
	CODE		CONTROL
	On	Normal Operation	—	—	—
	Off	Hardware Failure	No gas heating.	—	Loss of power to the IGC. Check 5 amp fuse on IGC, power
					to unit, 24V circuit breaker, transformer, and wiring to the
					IGC.
	1 Flash	Indoor Fan On/Off Delay	5 seconds subtracted from On	Power reset.	High temperature limit switch opens during heat exchanger
		Modified	delay.		warm-up period before fan-on delay expires.
			5 seconds added to Off delay		High temperature limit switch opens within
			(3 min max).		10 minutes of heat call (W) Off.
					See Limit Switch Fault.
2	Flashes	Limit Switch Fault	Gas valve and igniter Off.	Limit switch closed, or heat	High temperature limit switch is open. Check the operation
			Indoor fan and inducer On.	call (W) Off.	of the indoor (evaporator) fan motor. Ensure that the sup-
					ply-air temperature rise is within the range on the unit
					nameplate. Check wiring and limit switch
					operation.
3	Flashes	Flame Sense Fault	Indoor fan and inducer On.	Flame sense normal.	The IGC sensed a flame when the gas valve should be
				Power reset for LED reset.	closed. Check wiring, flame sensor, and gas valve opera-
					tion.
4	Flashes	Four Consecutive Limit	No gas heating.	Heat call (W) Off.	4 consecutive limit switch faults within a single call for heat.
		Switch Fault		Power reset for LED reset.	See Limit Switch Fault.
5	Flashes	Ignition Fault	No gas heating.	Heat call (W) Off.	Unit unsuccessfully attempted ignition for 15 minutes. Check
				Power reset for LED reset.	igniter and flame sensor electrode spacing, gaps, etc. Check
					flame sense and igniter wiring. Check gas valve operation
					and gas supply.
6	Flashes	Induced Draft Motor Fault	If heat off: no gas heating.	Inducer sense normal, or	Inducer sense On when heat call Off, or inducer sense Off
			If heat on: gas valve Off and	heat call (W) Off.	when heat call On. Check wiring, voltage, and operation of
			inducer On.		IGC motor. Check speed sensor wiring to IGC.
7	Flashes	Rollout Switch Lockout	Gas valve and igniter Off.	Power reset.	Rollout switch has opened. Check gas valve operation.
			Indoor fan and inducer On.		Check induced-draft blower wheel is properly secured to
					motor shaft.
8	Flashes	Internal Control Lockout	No gas heating.	Power reset.	IGC has sensed internal hardware or software error. If fault
					is not cleared by resetting 24 v power, replace the IGC.
9	Flashes	Temporary Software Lockout	No gas heating.	1 hour auto reset, or power	Electrical interference is disrupting the IGC software.
				reset.

LEGEND

IGC — Integrated Gas Unit Control LED — Light-Emitting Diode

NOTES:

1.There is a 3-second pause between alarm code displays.

2.If more than one alarm code exists, all applicable alarm codes will be displayed in numerical sequence.

3.Alarm codes on the IGC will be lost if power to the unit is interrupted.

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