System Diagnosis
Flame Failure / Watchguard Mode. The system has failed to ignite or lost flame signal multiple times.
Lennox | LED Status Codes (DS1 & DS2)
Error Code Alt Slow Flash / Alt Slow Flash
Troubleshooting guide for the Lennox LED Status Codes (DS1 & DS2) system fault Alt Slow Flash / Alt Slow Flash.
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 flame sensor, gas valve issue, igniter failure, gas supply issue.
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