On the page here you can find the recommendations on troubleshooting with Concord furnace. If you notice something unusual in your furnace work, or there are some serious issues which make you think there is a problem, address these lists.
In the tables below you can find Concord Furnace error codes and their explanations. With the description you can also get some advice on what to do in case of the breakdown. For example, Concord furnace 3 flashes mean problems with pressure, and Concord furnace 6 flashes mean ignition problems. There are detailed recommendations on what to check for and what to fix if you experience these flashes or signals.
Concord 96G1E Furnace Error Codes
Control has 24 VAC power
Pressure switch did not open, check for obstructed pressure tubing
Pressure switch did not close, or re-opened- Check for: excessive wind, proper vent size, defective inducer motor, low inducer voltaqe, defective pressure switch, inadequate combustion air supply, disconnected or obstructed pressure tubing, low inlet gas pressure, restricted vent, condensate cloqqed
Limit circuit fault-a limit or flame rollout is open. Check for: restricted vent, proper vent sizing, loose blower wheel, excessive wind, dirty filter, defective blower motor, defective switch or connections, inadequate combustion air supply
Abnormal flame proving signal-Flame is proved while gas valve is de-energized. Check for: leaky gas valve, stuck open qas valve
Failure to ignite or flame sense lost while running. Check for: Flame sensor must not be grounded, low inlet gas pressure, oxide buildup on flame sensor,
Manual valve shut off, proper flame sense microamps, gas valve defective or gas valve turned off, defective hot surface iqniter, control qround continuity,
Inadequate flame carryover or rough ignition, green/yellow wire MUST be connected to furnace sheet metal.
Limit circuit lockout- Lockout occurs if the limit or flame rollout is open longer than 3 minutes. Control will auto reset after 3 hours. Refer to #4
Gas heating lockout-Control will NOT auto reset. Check for: mis-wired gas valve, defective control valve
Polarity-Line voltage, polarity reversed. If twinned, refer to twinning kit instructions.
1 + 2
Blower on after power up- Blower runs for 90 seconds, if unit is powered up during a call for heat (R-W closed) or (R-W) opens durinq blower on delay.
6 + 1
Ignition lockout- Control will auto-reset after 3 hours. Refer to #6.
Secondary voltage fuse is open- Check for: door switch not closed, 115VAC at LI and neutral, 24VAC RED and COM BLUE, 24V Fuse 3A, short circuit in secondary voltage (24VAC wiring)
Control circuitry lockout- Auto-reset after one hour
Gas valve relay stuck open- Flame sense circuit failure, software check error, reset power to clear lockout, replace control if status code repeats.
Concord 80G1 Furnace Error Codes
RED LED Flash Code
Diagnostic Codes t Status of Furnace
No power to control or board fault detected
Control powered - displayed during all modes of operation if no errors are detected
Reverse Line Voltage Polarity
Improper Earth Ground
Burner failed to light, or tost flame during heat demand
Low Flame Signal - check flame sensor
Watchguard - burner failed to light, exceeded maximum number of retries or recycles.
Primary or Secondary Limit Open or Watchguard Mode - Limit Switch Open Longer than 3 minutes
Rollout Switch Open
Pressure Switch failed to close or opened during heat demand
Watchguard - Pressure Switch opened 5 times dunng one heat demand
Pressure switch stuck closed prior to activation of combustion air inducer
Flame Sensed without gas valve energized
Low Line Voltage
Concord 92G1 Furnace Error Codes
No power to control or control hardware fault detected