Coleman Furnace 11 Red Flashes (CP9C Echelon Modulating)
Hard lockoutShown as: Eleven red flashes, two-second pause, repeating
Main blower failure. The main limit opened and did not reclose within five minutes, which the control reads as a failed blower motor or blower wheel.
Manual wording: “Eleven Red Flashes - Main blower failure - This flash code occurs when the main limit opens and fails to reclose within five minutes, indicating that the blower motor or blower wheel has failed.”
Documented for: CP9C Echelon modulating furnaces
Likely causes, most common first
- Failed blower motor
- Failed blower wheel
What you can safely check yourself
- Check and replace the air filter
- Open blocked supply registers and clear the return grille
When to call a technician
Blower motor or wheel replacement is a technician job. Stop resetting the furnace if the code returns.
A Coleman furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Source
- Installation Manual - Residential Gas Furnace with ECM Motor, Models TP9C*C, YP9C*C, CP9C*C, LP9C*C (Up to 98% Modulating Multi-position), 681292-UIM-B-1211 (Johnson Controls Unitary Products (Coleman), CP9C*C Coleman Echelon modulating gas furnace (manual also covers the identical TP9C, YP9C and LP9C chassis)) · checked 2026-08-25