GOODMAN ERROR CODE • TRI-STATE AREA
Goodman Error Code GC: Ignition Failure
Your Goodman furnace failed to ignite. Learn the causes and safe troubleshooting steps.
What is Goodman Error Code GC?
Goodman error code GC indicates an Ignition Failure. The gas valve opened during the ignition sequence, but flame was not established or detected by the flame sensor. After multiple attempts (typically 3-4), the system enters safety lockout.
This error appears on Goodman GMS, GMH, and GMSS series furnaces. The control board tracks the ignition sequence and displays GC when flame establishment fails.
If you smell gas, leave immediately and call your gas company from outside. Do not attempt troubleshooting.
Common Causes
Failed Hot Surface Igniter
The most common cause. Igniters crack over time and can't reach the 1,800°F needed for ignition. Look for an orange glow—no glow means a bad igniter.
Dirty Flame Sensor
Carbon buildup on the flame sensor prevents flame detection. If the furnace ignites briefly then shuts off, the sensor likely needs cleaning.
Gas Supply Issues
Closed manual valve, empty propane tank, or low utility gas pressure. Verify gas supply by checking other appliances.
Frequently Asked Questions
What is Goodman error code GC?
Goodman error code GC indicates an Ignition Failure. The gas valve opened but flame was not established or detected by the flame sensor after multiple ignition attempts.
What causes Goodman ignition failure?
Common causes include failed hot surface igniter, dirty flame sensor, gas supply issues (closed valve, low pressure), clogged burners, faulty gas valve, or control board problems.
How do I reset Goodman error code GC?
Turn off power for 30 seconds to reset the control board. If GC returns after one ignition attempt, there's a component failure requiring professional diagnosis.
Is Goodman error code GC dangerous?
The lockout is a safety feature preventing gas accumulation. If you smell gas, leave immediately and call your gas company. Never attempt to manually light a furnace with ignition failure.
How long do Goodman igniters last?
Goodman hot surface igniters typically last 3-5 years. They're consumable parts that naturally wear out. If your furnace is 3+ years old and won't ignite, the igniter is a likely culprit.
How long does it take to fix Goodman GC?
Most repairs complete in a single service visit. Igniter replacement takes 30-60 minutes. Flame sensor cleaning takes 15-30 minutes. Gas valve or control board replacement may take 1-2 hours. Our technicians carry common parts.
Can I see if the igniter is working?
With power on and the furnace calling for heat, carefully observe through the furnace window. The igniter should glow bright orange within 30-60 seconds of the draft inducer starting.
Why does my Goodman click but not ignite?
Clicking without flame usually means gas isn't reaching the burners. Verify the gas valve is open and other gas appliances work. If gas supply is confirmed, the gas valve may need service.
Can a dirty filter cause Goodman GC?
A dirty filter doesn't directly cause GC, but severe restriction can affect the overall system operation. Always replace dirty filters as part of troubleshooting any furnace issue.
What's the difference between GC and LC codes?
GC is Ignition Failure (can't establish flame). LC is Limit Circuit Fault (overheating). GC is a startup problem; LC is an operating problem typically caused by airflow restriction.
Can I clean the flame sensor myself?
Yes, with power off. The flame sensor is a thin metal rod near the burners. Remove its mounting screw and gently clean with fine steel wool or emery cloth. Avoid touching with bare hands.
Why does GC happen in cold weather?
Cold weather increases cycling, wearing igniters faster. Extreme cold can affect gas pressure. Ice blocking outdoor intake pipes can also cause ignition issues on high-efficiency units.
What if my Goodman ignites then shuts off?
Igniting then immediately shutting off typically indicates a flame sensor problem—it can't detect the flame. This is different from not igniting at all (usually igniter or gas supply).
Can a power surge cause GC?
Yes, power surges can damage igniters and control boards. If GC appeared after a power outage or surge, component damage is likely. A surge protector can prevent future damage.
Who repairs Goodman furnaces with GC in the tri-state area?
Dimatic Control LLC provides expert Goodman furnace repair throughout the tri-state area. Our technicians carry igniters and common parts for same-day repairs. Call (908) 249-9701.
Need Help with Goodman Error Code GC?
Same-day Goodman furnace repair throughout the tri-state area.
Call 908-249-9701