System Diagnosis
No Power. The furnace may not be receiving power. Check the breaker and fuse.
Troubleshooting guide for the Lennox LED Status Codes (DS1 & DS2) system fault Off / Off.
Missing voltage, inconsistent outputs, or a fault that changes when a connector is reseated.
Intermittent power quality and field wiring problems can mimic a failed board.
Use the ACLogics AI assistant to walk through this error code step-by-step.
Upload nameplate & symptoms
AI isolates the likely led status codes (ds1 & ds2) branch behind code Off / Off
Document the verified result and next action