What does Coleman code 8 Blinks mean?
Coleman furnace code 8 Blinks means flame was lost five times during one heat call, causing recycle lockout on the supported control family. Confirm the model number and diagnostic chart inside the furnace door before replacing parts.
What causes Coleman code 8 Blinks?
- A dirty or weak flame sensor
- Unstable gas pressure or burner flame
- Poor grounding or flame-sensor wiring
Can I troubleshoot Coleman code 8 Blinks?
- Confirm the gas shutoff has not been moved and the furnace panel is fully seated.
- Try one reset and watch whether the burners light and then shut off again.
How much does Coleman code 8 Blinks cost to fix?
A flame sensor cleaning or replacement typically costs between $100 and $600 nationally.
When should I call a technician?
Call a technician if flame drops out again or ignition becomes delayed or noisy.
Sources and model scope
Fault codes vary by model and control board. Confirm the diagnostic chart inside your furnace panel or the official manual before acting.
Scope used here: Johnson Controls integrated furnace controls using the documented 1–12 red-flash table.
- Johnson Controls Unitary Products: Gas Furnace Installation Manual
272441-UIM-E-0513 · Johnson Controls integrated furnace controls with the 1–12 red-flash table in this manual; other model families may differ.
Compiled by Warmlo Editorial · Reviewed August 2026
This is general information, not professional advice. Gas, electrical, and combustion repairs can be dangerous — when in doubt, call a licensed technician.