System Diagnosis
Limit Switch Open (Variant). The furnace has overheated or the rollout switch has tripped.
Lennox | LED Status Codes (DS1 & DS2)
Error Code Slow Flash / On
Troubleshooting guide for the Lennox LED Status Codes (DS1 & DS2) system fault Slow Flash / On.
Disclaimer: This information is for general reference. Error codes can vary by model and production year. Always refer to your machine's specific manual and the information printed on the unit itself.
Potential Causes & Solutions
- Dirty filter, blocked vents, bad blower motor, restricted airflow.
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