Bryant DURAPAC PLUS 581A Installation And Service Instructions Manual page 48

PROBLEM
Burners Will Not Ignite.
Inadequate Heating.
Poor Flame Characteristics.
Burners Will Not Turn Off.
LED FLASH
DESCRIPTION
CODE
On Normal Operation
Off Hardware Failure
1 Flash Indoor Fan On/Off Delay
Modified
2 Flashes Limit Switch Fault
3 Flashes Flame Sense Fault
4 Flashes Four Consecutive Limit
Switch Fault
5 Flashes Ignition Fault
6 Flashes Induced Draft Motor Fault
7 Flashes Rollout Switch Lockout
8 Flashes Internal Control Lockout
9 Flashes Temporary Software Lockout
LEGEND
IGC — Integrated Gas Unit Control
LED — Light-Emitting Diode
Table 35 — Heating Service Analysis
CAUSE
Misaligned spark electrodes.
No gas at main burners.
Water in gas line.
No power to furnace.
No 24 v power supply to control circuit.
Miswired or loose connections.
Burned-out heat anticipator in thermostat.
Broken thermostat wires.
Dirty air filter.
Gas input to unit too low.
Unit undersized for application.
Restricted airflow.
Blower speed too low.
Limit switch cycles main burners.
Too much outdoor air.
Incomplete combustion (lack of combustion air)
results in:
Aldehyde odors, CO, sooting flame, or floating flame.
Unit is locked into Heating mode for a one minute min-
imum.
Table 36 — IGC Board LED Alarm Codes
ACTION TAKEN BY
CONTROL
—
No gas heating.
5 seconds subtracted from On
delay.
5 seconds added to Off delay
(3 min max).
Gas valve and igniter Off.
Indoor fan and inducer On.
Indoor fan and inducer On.
No gas heating.
No gas heating.
If heat off: no gas heating.
If heat on: gas valve Off and
inducer On.
Gas valve and igniter Off.
Indoor fan and inducer On.
No gas heating.
No gas heating.
Check flame ignition and sensor electrode positioning.
Adjust as needed.
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.
Drain water and install drip leg to trap water.
Check power supply, fuses, wiring, and circuit breaker.
Check transformer. Transformers with internal overcurrent protection
require a cool-down period before resetting. Check 24-v
circuit breaker; reset if necessary.
Check all wiring and wire nut connections.
Replace thermostat.
Run continuity check. Replace wires if necessary.
Clean or replace filter as necessary.
Check gas pressure at manifold. Clock gas meter for input. If too low,
increase manifold pressure or replace with correct orifices.
Replace with proper unit or add additional unit.
Clean filter, replace filter, or remove any restrictions.
Install alternate motor, if applicable, or adjust pulley to increase fan
speed.
Check rotation of blower, thermostat heat anticipator settings, and
temperature rise of unit. Adjust as needed.
Adjust minimum position.
Check economizer operation.
Check all screws around flue outlets and burner compartment.
Tighten as necessary.
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.
Wait until mandatory one minute time period has elapsed or power to
unit.
RESET METHOD
—
— Loss of power to the IGC. Check 5 amp fuse on IGC, power
to unit, 24V circuit breaker, transformer, and wiring to the
IGC.
Power reset. High temperature limit switch opens during heat exchanger
warm-up period before fan-on delay expires.
High temperature limit switch opens within
10 minutes of heat call (W) Off.
See Limit Switch Fault.
Limit switch closed, or heat High temperature limit switch is open. Check the operation
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.
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.
Heat call (W) Off. 4 consecutive limit switch faults within a single call for heat.
Power reset for LED reset. See Limit Switch Fault.
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.
Inducer sense normal, or Inducer sense On when heat call Off, or inducer sense Off
heat call (W) Off. when heat call On. Check wiring, voltage, and operation of
IGC motor. Check speed sensor wiring to IGC.
Power reset. Rollout switch has opened. Check gas valve operation.
Check induced-draft blower wheel is properly secured to
motor shaft.
Power reset. IGC has sensed internal hardware or software error. If fault
is not cleared by resetting 24 v power, replace the IGC.
1 hour auto reset, or power Electrical interference is disrupting the IGC software.
reset.
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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REMEDY
PROBABLE CAUSE
—