What It Means
Blower motor fault or normal operation depending on system model.
Lennox All Systems
Lennox Error Code Slow Flash / Slow Flash
Troubleshooting guide for the Lennox system fault Slow Flash / Slow Flash.
ACLogics Fix Lennox code Slow Flash / Slow Flash See how ACLogics handles it → Fix Slow Flash / Slow Flash step-by-step
Possible Causes
- Blower motor failure.
- Control board issue.
Not sure which one it is — or if it's none of these? Try ACLogics today.
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.
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Full Diagnosis
Blower Motor Fault (Normal Operation with Call for Heat). If alternating, it may indicate a different issue, but simultaneous slow flash often means normal operation or blower issue depending on model. Consult manual.
All Recorded Causes
Blower motor failure, control board issue.
Verify Before Replacing Parts
- Confirm the exact Lennox model family and ds1 & ds2 context before acting on a generic code description.
- Confirm filter condition, blower operation, and coil cleanliness before replacing any controls — start by ruling out whether blower motor failure, control board issue.
- Measure airflow-related readings that match the symptom, such as temperature split or static pressure, and check whether the next candidate on the list.
- After the correction, run the system long enough to confirm the ds1 & ds2 fault does not return under normal load.
Not sure which system this Lennox code is on?
ACLogics has guided diagnostics for 16 Lennox fault codes and asks the right questions to narrow it down.
